CWINI
A preliminary investigation into
Cavity Wall Insulation in Northern Ireland
35%
10%
15%
15%
MARCH 2014
Contents
Foreword
4
Introduction
6
House condition surveys
8
Fuel poverty
12
Understanding cavity wall insulation
15
Survey scope & results
18
Mount Eagles case study
28
Recommended solutions
36
Benefits of a retrofit programme
40
Conclusions
42
Cavity Wall Insulation in Northern ireland
3
Foreword
Dear Reader
This report has been prepared by leading members
of the Northern Ireland home insulation industry,
who are committed to maintaining and raising
standards within their business sector.
All strive to deliver the highest possible level of
service, working to strict industry technical
standards set by Government and monitored by its
regulatory authorities.
It must be recognised that the Northern ireland
building stock has characteristics not found
elsewhere. It is relatively modern with over half
being constructed in the last 50 years, and whilst
thermal performance standards came into force in
1973, thermal efficiency has not been a focus of
Building Control. Additionally, many installations took
place at a time when the industry was not subject
to the same stringent controls and regulation as is
the case today.
For example, cavity wall insulation is installed to an
Agrement Certificate issued by the British Board of
Agrement (BBA).
In this report we have documented instances where
our members have found poor and inefficient home
insulation, which directly impacts on the level of fuel
poverty in the Province.
Both the government recognised BBA and the BSI
carry out regular – and often unannounced – site
visits to ensure that standards are being maintained
by all the Province’s certified insulation installers and
that installations are covered by the independent
CIGA 25 year guarantee.
We believe that the samples in these pages illustrate
the problem. We therefore conclude this report with
a list of simple suggestions which we hope might
get the debate moving and help us all better
understand the issues surrounding the importance
of efficient home insulation.
Over the past five years our industry, like many
others in the construction sector, has been hit hard
by the recession; fewer houses being built, tighter
household budgets and reduced Government
assistance have presented us with many difficulties.
If you would like to discuss the report further or
request any further details please feel free to
contact me: Bill McCandless, at
bill.mccandless@energystoreltd.com.
The apparent assumption is that the Northern
Ireland housing stock is well insulated. As an
industry we do not believe this to be the case.
4
“
Thank you once again for your interest.
Yours Sincerely,
Bill McCandless
Managing Director, Energystore
In this report we highlight the apparent gap
between actual and assumed standards of
insulation in order to raise awareness and
stimulate debate.
”
Cavity Wall Insulation in Northern ireland
Cavity Wall Insulation in Northern ireland
5
Introduction
On Monday 11th November 2013 the
Although this is partly due to the greater
evidence that both properties with older
Northern Ireland Assembly debated
reliance on home heating oil we believe
insulation and also some relatively newly
and passed a motion, put forward by
there is no doubt that the number of
built properties could be performing less
Alex Easton MLA, calling on the
properties with no cavity wall insulation
well than assumed. The 2011 Housing
or underperforming cavity wall insulation
Condition Survey states:
Social Development Minister to:
is a contributing factor.
“The proportion of the stock with full
“Initiate a review of the range of
insulation materials used in Housing
The proper use of thermal insulation in
cavity wall insulation remained
Executive homes, to assess the heat
domestic housing can significantly
broadly similar to the 2009 findings.
retention properties of the material
contribute to reducing the annual energy
In 2011, 503,120 dwellings had full
used and to maximise the cost
cost. However cavity wall insulation
cavity wall insulation which
effectiveness of insulating the
installers in Northern Ireland are regularly
accounted for two thirds of the total
contacted by householders whose
housing stock.”
homes.”
homes are cold, damp and have high
The Minister, Nelson McCausland,
heating bills even though they may
The insulation industry does not dispute
highlighted his commitment to ensuring
already have home cavity wall insulation.
the numbers of houses insulated, but
this report and the debate at Stormont
that social houses are insulated to a high
standard, and Fra McCann MLA
expanded the debate by stating:
An initial series of tests on a range of
certainly question the effectiveness of the
hard-to-heat homes found that in heating
insulation installed.
retention terms they were simply
“Any review or strategy needs to be
inadequate. Consequences for the
On page 28 of this report a case study
widened to deal with all housing due
householder include high heating bills,
focuses on the Mount Eagles Estate in
to the need to protect vulnerable
fuel poverty and the risks associated
West Belfast comprising approximately
tenants regardless of the housing
with cold induced health problems.
600 homes built from 2000.
sector they live in”.
Complaints concerning high energy
We in the insulation industry welcome
Cavity Wall Insulation NI
costs, comfort and health matters
and support these comments and intend
This report is based on over 100
resulted in a number of inspections
that this report is used to raise
surveys, using boroscopes to look inside
being carried out between February and
awareness, to add to the debate and to
the walls of each house, undertaken by
May 2013. These initial inspections were
act as an aid to decision makers and any
leading members of the Northern Irish
carried out by one of our members on
parties interested in energy efficiency
insulation industry over the last 12
behalf of the Mount Eagles Residents
and fuel poverty in Northern Ireland.
Higher energy costs
months and reflects on the performance
Association and the findings led to the
of cavity wall insulation which has been
Centre for Sustainable Technologies at
in use for a number of years. The house
the University of Ulster being engaged to
surveys cover a wide geographic spread
investigate the performance and quality
Northern Ireland residents pay
from Derry to Newry and include a range
of cavity wall insulation in dwellings in
significantly more for their energy than in
of house types, ages, external finishes
Northern Ireland using a house in Mount
the rest of the UK. Fuel Poverty in
and occupancy demographics.
above the UK average of 19%.
6
Eagles to both test their theories and find
a possible solution. Their results are
Northern Ireland, at 42% in 2011, is well
There is anecdotal and scientific
reported on page 33.
Cavity Wall Insulation in Northern ireland
Recommendations
energy costs – whenever suitable – must
Following a recent set of tests on hard-
always be the first ‘port of call’ and is
to-heat-homes in the North Down area,
recommend industry-approved solutions
unquestionably the most cost-effective
John Ross, Research Lecturer on
to maximise the savings potential and
treatment and energy reduction measure
Renewable and Sustainable
demonstrate the multiple wider
in any property after loft insulation.
Northern Ireland’s insulation installers will
advantages to Northern Ireland from a
programme of retrofit energy efficiency
and insulation upgrades in terms of
economic, social and environmental
benefits.
These benefits include boosting
economic activity and tax revenues,
creating jobs in the hard hit construction
sector, reducing greenhouse gas
emissions, providing consumers with
savings on energy bills, tackling fuel
Technologies at South Eastern Regional
College (SERC) wrote:
The Province’s installers believe
that a national scheme to
upgrade cavity wall insulation
and a mandatory insistence on
‘fabric first’ before any other
energy efficiency measures –
such as heating upgrades or
renewables – is the only realistic,
practical and cost-effective way
to manage the exposure to high
energy prices.
poverty and creating healthier and
“The need to insulate before any
other expenditure is paramount in
dealing with providing comfort and
low living costs.
The reality is simple: we can reduce
fuel poverty, tackle climate change,
improve our housing stock, tackle
social inclusion, create jobs, reduce
hospital waiting lists, improve health
costs and help meet reductions in
our energy dependency.
warmer living environments.
Investment in insulation will substantially
increase the energy efficiency of the
This should be viewed not as a cost
Installers wish to demonstrate that the
existing Northern Ireland housing stock –
but an investment which will repay
use of cavity wall insulation to reduce
a vital part of the economy’s infrastructure.
itself in no time.”
“
Northern Ireland’s insulation installers will recommend
industry-approved solutions and demonstrate the multiple
wider advantages to Northern Ireland from a programme of
retrofit energy efficiency and insulation upgrade in
terms of economic, social and environmental benefits.
Cavity Wall Insulation in Northern ireland
”
7
The Housing Condition
Survey (HCS) and EPCs
The influence of inaccurate data on fuel poverty
Background
All tenures and types of housing are
The HCS is seen as providing a reliable
included and the HCS provides a wealth
assessment of the energy efficiency of
is based on assumptions regarding the
of information which is readily available
the housing stock in Northern Ireland.
energy efficiency of our housing stock
to, and used by, government
The NIHE 2011 House Condition Survey
that may be unrealistic.
departments, government agencies, the
voluntary sector, charities, universities
Leading members of the Province’s
and many private sector interests.
insulation industry therefore surveyed
over 100 properties across Northern
The findings of the HCS are used in
Ireland and 25 in Mount Eagles, Belfast.
decision making for various government
The series of intrusive wall inspection
bodies, particularly in the social sector
tests used a boroscope to look inside
with regard to investment in energy
the walls of these hard-to-heat-homes
efficiency measures.
and found that, for various reasons, a
proportion performed poorly when it
NIHE is Northern Ireland’s Home Energy
came to retaining generated heat.
Conservation Authority. It’s primary
objective is to improve energy efficiency.
There is further documented anecdotal
The HCS is the primary data source for
and scientific evidence that properties
assessing progress towards improved
with older insulation are performing less
energy efficiency.
well than properties which have just
been insulated.
The 2011 HCS shows the total dwelling
The number of houses with
cavity wall insulation is not in
question but rather the condition
and effectiveness of the actual
insulation installed.
a net increase of 20,000 since 2009.
stock in Northern Ireland to be 760,000,
Key HCS Objectives
HCS survey methodology
The 2011 HCS was completed using
mobile field computers designed to
enhance data quality and a faster turn
round of results.
Eighteen fully qualified surveyors
undertook the field work which due to
budgetary pressures saw the sample
reduced from 3,000 in HCS 2009 to
2,030 randomly selected dwellings in
2011. Of the sample a total of 1,434 full
inspections were carried out.
None of the inspections involved
an internal inspection of the wall
cavities using either a boroscope
or any thermal imaging.
Either of these methods can help
identify defects or areas of heat
loss.
The HCS does not physically inspect loft
The HCS provides a comprehensive
insulation either. The HCS methodology
picture of the dwelling stock and it’s
uses the date of build alone to determine
What is the House
Condition Survey?
condition to allow comparative analysis
the levels of insulation present in a
of housing conditions in Northern Ireland
property. It should also be noted that
The Northern Ireland Housing Executive
with other parts of the UK. It provides
building control is not required to
(NIHE) is statutorily responsible to
robust estimates of important
physically inspect cavity wall insulation
regularly examine housing conditions
government measures, namely Decent
except to confirm that it has been installed.
and need. It does so via the House
Homes and the Housing Health and
Condition Surveys (HCS). The 2011 HCS
Safety Rating Standard (HHSRS) and
Another notable point is that... A house
is the eleventh such survey to be carried
also the levels of fuel poverty in Northern
must be built to the building
out in Northern Ireland since 1974.
Ireland.
requirements existing at the time
8
Cavity Wall Insulation in Northern ireland
House surveys
planning was approved. The date of the
The Housing Executive has reported in
build is often some years after this and
its House Condition Survey 2011 that
External walls
thermal requirements are not routinely
fuel poverty numbers have not increased
1973
enforced. Therefore age is not always an
in line with fuel price increases. It
U value of 1.70
accurate indicator of the type of
concludes that this is:
Mainly provided by Clinker block or
“largely as a result of significant
similar (or possibly if at all).
insulation used in a property. This is true,
not only of inspections carried out for the
HCS, but also of the assumptions made
in EPC reports.
investment, particularly in the social
sector, in new energy efficiency
measures such as heating
conversions, insulation and double
2011 HCS & Cavity
Wall Insulation
glazing by the Housing Executive in
its own stock and also by the Warm
Chapter 7 of the 2011 HCS deals with
energy and states that:
“the energy efficiency of a dwelling
Other factors such as insulation and
double glazing are also important”
“The proportion of the stock with full
cavity wall insulation remained
1984
highest standards it does not mean that
the household will automatically be
“The cost of fuel and low income will
remain important determinants of
whether a household is still in fuel
broadly similar to the 2009 findings.
poverty.”
In 2011, 503,120 dwellings had full
requirement for 28mm EPS (other
materials are given as options in differing
The 2011 HCS continues to indicate that
brought out of fuel poverty:
At 7.4 the HCS states:
This was the introduction of the
thicknesses ie wood wool slabs).
heating system and is insulated to the
source and heating type.
U value of 1.0
Homes Scheme in private homes.”
even if the dwelling is given an efficient
is determined primarily by the fuel
1977
The ‘regs’ give a series of options ranging
from 24mm to 46mm EPS depending on
the density of the masonry or insulation.
Other materials are given as options.
1990
U value of 0.6
The introduction of the 50mm EPS batt.
At this point the full fill of a 75mm or
100mm cavity, of any of the normal
cavity wall insulation which
materials was well in excess of the
accounted for two thirds of the total
minimum requirement.
housing stock.”
Building Regulations
timeline & insulation
The table below (taken from table 7.7
There has been a U value requirement
HCS Dwelling Age – Wall Insulation)
from 1973, but it was catered for by
indicates that 100% of all houses built
using insulating block work for the first
after 1980 have full cavity wall insulation,
number of years (pumice, thermocrete
as do 69% of houses built between
etc). The later requirements provided for
1964 and 1965, and 53% of houses built
different thicknesses of insulation
in the period 1945 to 1964.
depending on the types of masonry used.
Pre 1919
10
TOTAL
Number
Percent
Number
Percent
Number
Percent
Number
*
0.4%
32040
36.5%
55,300
63.1%
87,660
1919 - 1944
*
1945 - 1964
7,1330
1965 - 1980
At this point the full fill of a 75mm or
100mm cavity, of any of the normal
material remained well in excess of the
minimum requirement.
2006
At this point the full fill material needed to
No wall
insulation
Partial CWI
Internal or dry lining
Introduction of the 60mm EPS batt.
Introduction of the 60mm PIR type batt.
DWELLINg AgE – WALL INSULATION
Full cavity
wall insulation
1994
17,920
26.3%
37,090
54.4%
68,130
53.2%
19,310
14.4%
43,320
32.3%
133,960
117,650
69.4%
13,960
8.2%
37,940
22.4%
169,550
Post 1980
300,700
100%
*
0%
*
0%
300,700
TOTAL
503,120
66.2%
83,230
11%
173,650
22.8%
760,000
be ‘Platinum’ type.
The timeline of building control
requirements does not convince the
Northern Ireland insulation industry that
there has been 100% full cavity wall
insulation since 1980.
For most of the period since 1980 some
insulation or a partial fill of the cavity has
been required, but we feel it would be
correct to assume that the houses were
Cavity Wall Insulation in Northern ireland
47 Mount Eagles Drive
Wet Fibre in number 47
Dry Sparse Fibre
only insulated to the highest standards of
energy performance of the property.
recorded in the EPC as being of the
the day and that these standards would
The detached property was built in 2001
cavity wall type and are assumed to be
now fall well short of building control
with brick external walls and insulated
insulated and are given a performance
requirements.
with blown fibre. The residents reported
rating of ‘good’.
that the house was cold and cooled
This – as we know from our boroscope
Energy Performance
Certificate (EPC)
down very quickly once the heating is
survey of the property – is incorrect.
switched off. They also reported having
The EPC software does not allow for a
EPCs are mandatory in Northern Ireland
to wear outdoor clothing to keep warm.
to determine the energy efficiency of a
property prior to it being sold or rented.
They are carried out by qualified EPC
assessors using a software programme
that makes certain assumptions
regarding the property by the year of build.
An EPC rating is designed to provide a
measure of the building’s overall energy
variation of this rating as it is a measure
based on an assumed performance level
What the EPC said about
47 Mount Eagles Drive
47 Mount Eagles Drive achieved a ‘C’
rating in October 2009 at 71 with a
potential to go up to 76 (still band C) if
some recommended energy efficiency
measures were carried out.
calculated on the year the house was
built (as per the building regulations in
place at that time).
• The recommendations include
increasing loft insulation to 270ml, the
installation of low energy lighting and a
Band A condensing boiler.
efficiency and its environmental impact
The EPC does not accurately reflect
calculated in accordance with a national
the energy efficiency of 47 Mount
The most cost effective and
methodology that takes into account
Eagles Drive for the following
necessary recommendation: to
factors such as insulation, heating and
reasons:
ensure the cavity wall insulation is
used. The average for a house in
• In October 2009, the annual cost of
is not a criterion ever suggested
Northern Ireland is band E (rating 50).
heat, light and hot water (gas and
within an EPC.
free of defects, is not mentioned and
hot water systems, ventilation and fuels
electric) was £1,028. By 2012 this had
The EPC for
47 Mount Eagles Drive
risen to £1,558. Even allowing for energy
Finally, the EPC recommends Solar PV
inflation this is a rise of 51.5%.
should be considered.
47 Mount Eagles Drive was surveyed on
• The EPC provides a summary of the
The EPC does not accurately reflect the
7th February 2013 and the results clearly
home’s energy performance which
energy performance of 47 Mount Eagles
demonstrate that the EPC produced for
usually relates to characteristics in the
Drive. The rating if adjusted for the actual
the property in October 2009 is incorrect
build of the property.
state of the cavity wall insulation would
and not an accurate reflection of the
The walls at 47 Mount Eagles Drive are
be an ‘E’ or an ‘F’ rating.
Cavity Wall Insulation in Northern ireland
11
Fuel poverty
in Northern Ireland
Fuel poverty is produced by a
cheap energy is not an option, but
combination of the following three
reducing our reliance on energy
factors:
through energy efficiency is an
option in which the government,
• Energy prices
• Low income
• Energy efficiency
of the housing stock
whether at UK level or locally
through the Executive, can play
large part. I argue that Northern
Ireland’s housing stock is in a
particularly bad state. Northern
It is virtually impossible for a regionally
Ireland has more excess winter
devolved government to have much
deaths per head of population than
influence over the first two factors which
Finland”
variables. The Housing Executive
No of
Households
Percentage
3,200,000
15%
580,00
25%
Wales
370,000
29%
N. Ireland
290,000
42%
England
Scotland
Figure 1.1
Extent of Fuel Poverty
The NIHCS 2011 shows that the highest
are determined by national and global
acknowledge this in their report “NIHE
FUEL POvERTy IN THE UK: 2011
Fuel poverty is
defined as follows:
rates of fuel poverty are experienced by
those on the lowest incomes; it showed
Market Review 2013-2016” when
“A fuel poor household is one that
that 79% of those who have an annual
discussing the strategic perspective and
cannot afford to keep adequately
household income of less than £10,000
state:
warm at reasonable cost. The most
are in fuel poverty. In addition those on
“Although the rate of fuel poverty in
widely accepted definition of a fuel
low incomes in Northern Ireland have the
Northern Ireland reduced between
poor household is one which needs
least access to credit and bank facilities
2009 and 2011 to 42%, reducing it
to spend more than 10% of its
in the UK.
further remains a very difficult
income on all fuel use and to heat its
challenge in the short term, given
home to an adequate standard of
To protect health and well-being, all
that energy prices are to remain high
warmth. This is generally defined as
households require a minimum standard
and real household incomes are
20 degrees C in the living room and
of heating in their home. Households
falling. Improving the fabric of
18 degrees C in the other occupied
that are in Fuel Poverty struggle to afford
buildings can ameliorate the impact
rooms – the temperatures
this minimum standard and many go
of fuel poverty significantly, but
recommended by the World Health
without heat and light. Others go without
cannot eradicate it altogether.”
Organisation.”
essentials, such as food, in order to pay
(UK Fuel Poverty Strategy, 2001).
for heat and light.
This view was shared at the Assembly
debate on 11th November 2013 by
Northern Ireland has the highest
Those who cannot afford to heat their
Steven Agnew MLA who said:
prevalence of fuel poverty in the UK
homes to an acceptable standard live in
“Energy efficiency in our housing
(see Figure 1.1), and one of the
cold and damp conditions for many
stock is absolutely key to tackling
highest in the EU, with the current
months. Tackling Fuel Poverty impacts
fuel poverty... Government can have
estimate indicating that 42% of
positively on health and well being.
little impact on fuel prices. However
households in Northern Ireland are
they can invest in energy efficiency.
experiencing fuel poverty (NIHE,
The most significant impacts on physical
So I think we have to accept that
2013).
health are manifest among children;
12
Cavity Wall Insulation in Northern ireland
Fuel poverty
impacts on mental well being are found
from early adolescence onwards.
In some circumstances the impact of
Fuel Poverty is death:
In NI it is estimated that an
average of 1,200 people die
prematurely each year as a
result of living in cold
conditions.
The Marmot Review Team (2011)
collated studies concerning the health
impacts of cold homes, and concluded
that the evidence “shows the dramatic
impact that cold housing has on the
population in terms of cardiovascular and
respiratory morbidity and on the elderly
in terms of winter mortality. It also
highlights the stark effect that fuel
poverty has on mental health across
many different groups, while also having
an impact on children and young
people’s well-being and opportunities.
Once the trade-off issues for at-risk
households are addressed, energy
efficiency interventions always bring
multiple health and environmental gains”.
These gains were quantified in the
Northern Ireland cost-benefit analysis
conducted by Professor Christine Liddell
in 2008 which concluded that, for every
£1 invested, 42 pence was returned in
quality of life gains.
Current Energy Efficiency
Funding in Northern Ireland
The Department for Social Development
DSD’S 2011 Fuel
Poverty Strategy
In April 2011 the Department for Social
draft budget proposals, the aim of
eradication of fuel poverty is more
uncertain.
Development launched its fuel poverty
strategy for Northern Ireland Strategy
set out the Department’s vision for the
Programme for government
in Northern Ireland
future:
The Programme for Government (PFG)
“A society in which people live in a
introduce and support a range of
“Warmer Healthier Homes”. The strategy
2011-2015 includes a commitment to
warm, comfortable home and need
initiatives aimed at reducing fuel poverty.
not worry about the effect of the
The OFMDFM is responsible for that
cold on their health”.
commitment.
The strategy identified 4 key areas for
The NI Executive Economy and Jobs
action to tackle fuel poverty in the future:
initiative (Nov 2012) also includes a
• Targeting of Resources
to boost economic activity through the
commitment to bring forward proposals
• Improving Energy Efficiency
retrofitting of energy efficiency measures
• Achieving Affordable Energy
into homes. It is in this context that
• Building Strong Partnerships
OFMDFM are now looking to explore a
domestic energy retrofit programme.
By focusing action on these four key
areas, the strategy aims to target
• We cannot assume that all houses
(DSD) have the lead responsibility for
vulnerable people who struggle most to
post 1980 have 100% effective cavity
tackling fuel poverty and to promote
heat their homes and for whom the
wall insulation as stated by the HCS
energy efficiency in residential
positive health impacts of a warm home
2011. It is vital that any money spent on
accommodation under the Domestic
are most evident.
energy retrofit aimed at reducing fuel
energy Efficiency (Northern Ireland) order
1999. DSD funds the Warm Homes
Scheme (WHS) and the Boiler
poverty must address fabric first.
Eradication of fuel poverty must
continue to be a main objective.
Replacement Scheme (BRS).The Utility
• There is no point installing a new high
efficiency boiler in a house when all the
Regulator manages the NI Sustainable
With recession, the current Northern
heat is lost through the walls or the
Energy Programme.
Ireland economic environment and the
ceiling.
14
Cavity Wall Insulation in Northern ireland
Understanding
cavity wall insulation
Why Cavity Wall Insulation?
35%
10%
15%
According to the Energy Savings
Trust (EST):
“Cavity wall insulation is the single
15%
The EST list
the benefits as:
The EST concludes that:
“Cavity wall insulation can reduce
the heat loss through cavity walls by
most cost-effective low risk energy
• Reduced fuel bills
up to 40 per cent.
efficiency measure available for the
• A warmer house that stays
It can also lead to reduced heating
existing housing stock, after loft
warmer longer
costs and improved comfort levels.
insulation. It can be installed without
• Reduced condensation
Payback (savings against costs)
major disruption to occupants and it
• Fewer draughts
times are estimated at between two
needs no maintenance.”
• Benefits to the environment
and three years.”
Cavity Wall Insulation in Northern ireland
15
Understanding cavity wall insulation
How does Cavity Wall
Insulation Work?
Partial fill cavity insulation
Since the 1930s the vast majority of
a rigid or semi-rigid insulation board to
Partial fill cavity insulation is the fixing of
the inner leaf of the cavity during
homes have been built with cavity walls.
construction of the external walling.
illustration courtesy of CIGA
The reason for the cavity is to stop wind
driven rainwater penetrating through to
the inside of the property and causing
dampness.
Over the years the width of cavities has
increased from a standard 50ml to up to
– and in excess of –100ml.
The Science behind it...
The thermal insulating property of a
Partial fill board does not fill the entire
cavity and leaves a gap. This was the
preferred option to improve thermal
performance when building regulations
required insulation post 1980.
There are three types of
board that can be used:
Since the 1980s the building regulations
material is expressed as it’s thermal
• EPS or Jablite board
have required new houses to be built
conductivity. The lower the thermal
• Phenolic Board
with insulation in the cavity and as long
conductivity the greater the material is
• Mineral Fibre Batt (not widely used
as they are built properly, this insulation
able to resist heat flow and therefore the
in Northern Ireland).
should not compromise the walls’
better it will act as an insulator. A wall
resistance to rain penetration.
that is well insulated will have a low Uvalue whereas one which is poorly
Houses built prior to 1980 will have an
insulated will have a high U-value.
empty cavity which can be retro filled
Partial Fill to Full Fill
Cavities that were built with rigid or semirigid board fixed to the inner leaf during
construction can now be upgraded with
using either mineral wool (fibre), EPS
bead or Foamed insulants. If the cavity is
Full Fill cavity construction
left empty air movement through the
Where exposure and quality of
cavity cools down the inner leaf and as
construction are appropriate fully filling
the outside temperature drops more and
the cavity with insulation is acceptable. It
more heat is lost. Filling the cavity with a
can either be filled during construction
water repellent insulating material
using boards or retrospectively using
reduces this heat loss.
blown bead, fibre or foam.
As with all insulation (either new build or
Introducing cavity insulation when the
retro fit) the existing cavity walling, the
wall is erected allows inspection of the
degree of exposure, the width of the
completed cavity to ensure it is free from
cavity, the condition of the external wall
debris and ensure that wall ties and
will all influence whether the wall is
cavity trays are clean and correctly
suitable for filling. Although most
installed.
BBA approval to a full fill cavity using
bonded bead. The property will therefore
benefit from higher levels of thermal
insulation. This can also be used to
eradicate issues of damp and mould in
houses with only partially filled cavities.
Due to the complexity of the process,
the quality of the survey is deemed
critical and is required to be at a level
over and above that carried out for
conventional installations.
Insulation Top Ups
traditional cavity walls can be filled, an
The topping up of any cavity wall
assessment of each property should
insulation is not certified by BBA and
always be carried out to determine the
should not be carried out. Where fibre
suitability of the walls.
has slumped, foam has disintegrated or
The various cavity wall insulation systems
alterations there is no suitable system to
and the installing companies have to be
“top up”.
bead has come out during building
approved by the British Board of
Agrement (BBA) or Irish Agrement Board
Topping up existing cavity wall insulation
(IAB). These bodies are responsible for
will render void any CIGA guarantee and
the technical surveillance that monitors
this process on behalf of the industry.
16
could lead to additional problems relating
100ml cavity fully filled with graphite bonded bead
to damp and mould.
Cavity Wall Insulation in Northern ireland
Understanding cavity wall insulation
Cavity Extraction
Whilst small cavities can be treated by
‘reblowing’ with the same material, in
other cases it should be extracted first.
Once the cavity has been cleared and
inspection ensures it is free from all
debris, the cavity can then be refilled
using a BBA approved system and a
CIGA guarantee provided.
Cavities can be cleared of blown fibre,
foam, blown bead and rubble under the
BBA process. Cavities cannot be cleared
of insulation board, whether full fill board
Cavity Extraction taking place at a property in Lisburn
or partial fill under the BBA approved
methodology.
The two main categories of
Cavity Wall Insulation:
Category 1
Cavity Wall Insulation installed at
time of Wall Construction
The three types of board that can be
used are EPS or jablite board (the most
common found in Northern Ireland),
phenolic board or mineral fibre batt. They
will either fully fill the cavity or be a partial
fill installation. Partial fill Insulation board
must be secured to the inner leaf
correctly to leave a cavity to allow water
to fall away.
The three main types of insulation
• Foam
fitted in this way are:
Foam is usually either:
• Blown Mineral Wool (Fibre)
1. UF Foam
Fibre relies largely on trapped air for
UF foam consists of a resin and a
much of its insulating properties. It
hardener solution injected with
should be installed according to its
compressed air into the cavity via a
agreement certification and, as with all
predetermined drill pattern.
systems, it is crucial that notice is taken
The cavity is filled from the bottom
of rainfall exposure zones and the
upwards using indicator sticks in the
condition of the cavity prior to install.
adjacent injection holes to show the
For the fibre to perform effectively it
mixing of the product and the running
extent to which the cavity has filled. The
should be installed by a specialist trained
conditions during install should be
contractor using the correct drill pattern
closely monitored to ensure quality and
to ensure the fibre fills the holes at the
efficiency.
correct density.
The foam will harden and shrink as it
• Blown Bead
dries. UF foam produces formaldehyde
EPS beads are spherical and have
vapour as it hardens which may enter
diameters varying from 2mm to 8mm.
the building if the inner leaf is not well
Category 2
They are free flowing and therefore
sealed. Adequate ventilation is necessary
Cavity Wall Insulation installed after
require less drill holes than fibre as an
to remove traces of formaldehyde.
wall constructed (new build or
adequate fill is easier to achieve.
2. Polyurethane Foam
retrofit)
Beads are coated with adhesive as they
Polyurethane cavity wall foam consists of
Whatever type of cavity wall insulation is
are injected to limit escape through
thin liquids mixed together and injected
used to fill the cavity after the wall is
cracks and openings.
into the cavity wall. The mixture expands
in the cavity adhering to both leaves.
constructed, it must be carried out by an
approved BBA contractor who will
White bead has now largely been
initially assess whether the walls are
replaced by grey, silver or graphite bead
As a closed cell product it is very difficult
suitable for CWI. The installation method
which is 20% thermally more efficient at
for water to pass through it and the
will vary depending on the type of
only a fraction of the cost more to
thermal insulation value of the foam is
system used.
produce.
very good.
Cavity Wall Insulation in Northern ireland
17
The front elevation of a detached house in Brerton Crescent, Belfast
Survey scope and results
In response to customer concerns, a survey of over 100 houses was conducted. A sample of ten
are included here. The results illustrate the inefficiency and consequences of poor and/or
underperforming cavity wall insulation*
Why Survey?
cavities with large voids. Thermal
“it used to take up to five hours to
The detached house above was built in
imaging also demonstrated heat loss
heat, but since my insulation has
Belfast in 1988. It is structurally sound
throughout the house and confirmed that
been sorted, it’s only taking an hour.
and in good condition and should –
the insulation was ineffective. The 100ml
I can’t wait to see the effect this will
have on my heating costs”.
according to the 2011 House Condition
cavities of the house had been insulated
Survey – have full cavity wall insulation.
with URF foam at the time of build, but
If an EPC were to be carried out on the
this appears to have disintegrated.
property, this would also assume full
cavity wall insulation.
The home owner was shocked to
discover that following an extraction of
A Survey of over
100 Houses
Had the above property been a one off
or indeed an unusual case the insulation
The home owner contacted a local
the remaining foam from the entire
industry in Northern Ireland could write it
insulation installer to investigate why the
house, only one bag of URF foam was
off to bad workmanship or some other
house is costly to heat and does not retain
removed.
heat once the system switches off. There
cause. However there are increasing
numbers of concerned householders
were signs of water penetration on the
The house has since been reinsulated
who already have cavity wall insulation
inside of the right gable and back wall.
with bonded bead and the home owner
but find that their home is still cold and in
The house was inspected with a
has noticed a big difference in the warmth
instances damp with high heating bills.
boroscope and the images showed the
and comfort of the property saying:
It is normally one or more of the following
*Details of the full survey are available on request
18
Cavity Wall Insulation in Northern ireland
Damp visible on the back wall (adjacent to the empty rear wall cavity)
One bag! The total amount of URF foam insulation material extracted from Brerton Crescent
A brick removed to show the left gable wall cavity with no signs of the URF
foam cavity wall insulation
pointers that will indicate
industry decided to formally investigate
were a mixture of social housing,
underperforming insulation:
the issues and seek solutions for them.
privately owned and privately rented.
• The home is hard to heat
• The home cools quickly when the
heating system is turned off
• Mould and/or excess condensation
is present
The Northern Ireland insulation industry
The HCS 2011 states:
in 2013 looked at the performance of
“The proportion of the stock with full
cavity wall insulation which has been in
cavity wall insulation remained
use for a number of years by intrusively
broadly similar to the 2009 findings.
surveying in excess of 100 properties.
In 2011, 503,120 dwellings had full
heat-homes consistently found that in
This does not include the 25 house
cavity wall insulation which
heating retention terms they were simply
surveyed in Mount Eagles.
A series of tests on a range of hard-to-
accounted for two thirds of the total
housing stock.”
inadequate.
The surveys covered a wide geographic
The HCS states that 100% of all houses
With the complaints regarding hard-to-
spread from Derry to Newry and
built after 1980 have full cavity wall
heat-homes on the increase and having
included a vast range of house types,
insulation. However the assumption that
both anecdotal and scientific evidence,
house ages, external finishes and houses
it is performing effectively is not
that properties with older insulation could
that have either no existing cavity wall
consistent with the results of this survey
be performing less well than properties
insulation or are already insulated with
– examples of which are shown on the
which have just been insulated, the
fibre, foam, bead or board. The houses
following pages...
Cavity Wall Insulation in Northern ireland
19
Survey & scope results
SAMPLE ONE
Bangor, Co Down
The semi-detached bungalow in Bangor
pictured above was built post 1980 and
has blown fibre in the cavities.
Although the boiler was replaced in
November 2012 the tenants still found
the house to cool down very quickly
when the heating was turned off. There
are also problems with mould visible in
the front and back bedrooms. The
couple’s teenage son has asthma and
they have had to remove the doors of
the built in wardrobe in the back
bedroom to allow his bed to fit thus
Semi-detached bungalow in Bangor front elevation
protecting him from the mould.
At the time of the survey the tenants had
been without oil for three weeks as they
could not afford to fill the tank.
The survey clearly showed that cavity
wall insulation was sparse and voids
existent.
20
Mould visible around the bedroom window
Sparse fibre in back cavity beside bedroom mould
Cavity Wall Insulation in Northern ireland
Survey & scope results
SAMPLE TWO
Hilltown, Belfast
The detached house (right) – built in
1992 and insulated with blown fibre –
was surveyed in February 2013 following
complaints from the home owner that it
was costly to heat and that the house
cooled down quickly once the heating
Left wall cavity with wet clumpy fibre
was turned off. Signs of water ingress
were evident to the inside walls of the
sitting room.
The surveyor took photographs illustrating
that the original fibre had slumped to the
bottom of the cavity (right) and when
extracted was found to be wet.
This existing fibre cavity wall insulation
offers no effective heat retention.
Fibre residue in the bottom of the cavity
SAMPLE THREE
Lagmore, Belfast
This detached property was built in
approximately 2000 and is insulated
with blown fibre.
While building an extension the home
Bare brick; virtually no trace of insulation
owner noticed that the existing fibre
insulation was sparse and in some
areas virtually non-existent.
This explains why the rooms upstairs
are hard to heat and do not retain heat
when the heating is turned off.
Sparse fibre insulation
Cavity Wall Insulation in Northern ireland
21
Survey & scope results
The mid terrace property in Glenbawn Close, Belfast
Severe mould in the front bedroom
Mould on the ceiling of the dining room
The front gable cavity (behind which the bedroom mould is present) showing a void of insulation
SAMPLE FOUR
is insulated with blown fibre. The
The property at Glenbawn Close was
glenbawn Close,
Belfast
property’s tenants continually complain to
surveyed in March 2013 and found to
the landlord that the house is cold and
have only sparse fibre in some walls and
hard to heat, but most seriously, that
none in others.
The mid terrace property in Glenbawn
there is a major problem with mould and
This would explain the severe problems
Close, Belfast was built post 1980 and
condensation in all rooms.
with mould.
22
Cavity Wall Insulation in Northern ireland
Survey & scope results
SAMPLE FIvE
Strangford Park
Derry/Londonderry
This semi-detached bungalow was built in 1988 when
50ml insulation board was installed, as required by
building regulations at the time, leaving a 50ml gap.
As a result the house has only ‘partial filled’ cavities.
The property has an exposed gable wall and black
mould is visible in the rooms adjacent to the gable
end. The mould is most notable in the bedroom and
the skirting boards need to be cleaned regularly.
Cavity partially filled with EPS bond
Mould at skirting board against gable end wall
Mould in bathroom against gable end wall
Mould visible on ceiling of child’s bedroom
...And in the sitting room
SAMPLE SIx
Hawthorn Drive
Derry/Londonderry
This semi-detached property was built as recently
as 2007. Insulation board was installed at the
time of build. On inspection we found a 50ml gap
in the cavity. The cavity was therefore only
partially filled.
The tenant has repeatedly complained of damp
and mould to the landlord over several years. The
children’s bedrooms are the worst affected. The
tenant has had to wash away mould on a regular
basis.
It is most likely that the mould is as a result of the
poorly fitted insulation board at the time of
construction. A partial fill of the residual cavity
using high performance bonded bead would be
the recommended remedy.
Cavity Wall Insulation in Northern ireland
23
Survey & scope results
SAMPLE SEvEN
Helen’s Bay, Co Down
This detached bungalow was built in
1965 and has blown fibre in the original
part of the house. The property was
extended some years ago and during this
construction 25ml EPS or Jablite board
installed to the extension’s cavity walls.
Left elevation where the sparse fibre reveals a visible void
The home owner finds the house difficult
to heat and it cools down very quickly
once the heating is turned off.
On inspection in September 2013 the
fibre insulation was found to be
inconsistent. There were large voids
visible in all areas and some of it was wet.
Wet fibre in the right hand gable wall
Clipped board only partially fills the cavity in the extension
SAMPLE EIgHT
Bangor, Co Down
This semi-detached property was built in
1969 and was later insulated with URF
foam. The home owner says the home is
hard to heat and cools down rapidly once
the heating is turned off.
The survey revealed the URF foam to be
very sporadic and the home owner
decided to have it extracted. Only two
bags of foam were recovered from the
cavities.
The property was reinsulated with bonded
bead and the home owner has reported
“an unbelievable difference in the comfort
of the house”.
The photograph of the front elevation taken
during the extraction of URF foam, shows
where two bricks have been removed to
suck out the foam, as per the BBA approved
method. This was also done at the side of
the house. The foam is dislodged using an
airline through a series of 18ml holes drilled in
all elevations of the property
24
The cavity prior to extraction with only traces of URF foam
Survey & scope results
SAMPLE NINE
Dundonald, Belfast
The detached chalet bungalow (right) was
built in 1968 and was insulated using
URF foam in approximately 1980.
The home owner complained that the
house is hard to heat and that 500 litres
of oil lasts only five weeks during cold
weather. This is supplemented by electric
heating costing £40 per week. There is
also severe mould in the bedrooms to the
front and the rear.
The home owner therefore had the URF
foam extracted from all the cavities of the
house – only two bags of foam were
removed. The cavity was then refilled
with bonded bead.
The home owner is delighted with the
result and... “notices a big improvement
in the warmth of the house and how it
retains heat. The mould has also gone”.
Mould present in the bedroom
SAMPLE TEN
Housing
Condition Surveys
Bangor, Co Down
The detached bungalow in Bangor (right)
After 1945 all houses in
Northern Ireland were
constructed with cavities and
therefore we can assume from
the HCS that there are 604,200
houses in NI with cavities.
was built in 1968 and had fibre installed
to insulate the cavities in the 1980s.
The property suffers from cold and
dampness. The home owner reports high
heating costs and virtually no heat
The HCS states that 69% of
houses built between 1965 and
1980, and 53% of houses built
in the period 1945 to 1964 have
full fill cavity wall insulation.
retention.
The survey, carried out in March 2013,
revealed areas with large voids and
virtually no insulation and other areas
However – regarding houses
built post 1980 – the
assumption that the existing
cavity wall insulation is
performing effectively is not
consistent with the surveys
carried out and shown in our
samples.
where the insulation did not meet the
required densities to be effective.
There was also rubble and mortar
present in the cavity which was removed
along with the existing fibre insulation
during an extraction to be replaced with
bonded bead.
Cavity Wall Insulation in Northern ireland
Mould in the wardrobe
Mould around the internal door frame
25
Survey & scope results
“
Blown fibre at the correct density
If insulation is installed at a low
density and there are resulting
voids or gaps, these cold spots will
attract condensation and may
cause mould.
Survey Conclusions
Sparse fibre in a cavity
installation and the environmental
situation will produce poor energy
The houses surveyed back up much of
conditions (rainfall and exposure zones)
improvement outcomes if the level of
the desktop research carried out by the
that the material is exposed to.
thermal protection is as inadequate as
our surveys have found right across
University of Ulster, who in their report,
entitled ‘Investigating the performance
If insulation is installed incorrectly and
and quality of cavity wall insulation in
there are resulting voids or gaps, these
Northern Ireland’s varied housing stock.
existing domestic dwellings in Northern
cold spots will attract condensation and
Finally the World Health Organisation
Ireland’ identified several reasons for
may cause mould inside the property.
states that excessive dampness and
older properties performing less well.
Moisture is always attracted to the
mould are a threat to health.
coldest part.
Occupants of damp or mouldy buildings
Heat loss resulting from air infiltration will
such as respiratory infections, allergic
These include:
• Physical deterioration since
installation due to ageing
• Instability and slumping
• voids and air gaps
• Settlement
• Weathering
• Disturbance by operatives
following building repair or
modification
are at increased risk of health problems
be increased where cold external air is
rhinitis and asthma. Some people are
able to pass through the cavity due to
more sensitive to mould than others, and
low density insulation or poorly fitted
some groups are especially vulnerable.
insulation boards.
Additional effort should be made to keep
From our detailed boroscope surveys
babies and children, elderly people,
and inspections carried out in homes
those with allergies and asthma and
across Northern Ireland, it appears that
anyone who is immuno-compromised
the previous energy analysis for many
away from damp and mould.
homes is questionable.
Research shows that people living in
Funding being provided by government
accommodation are less likely to visit
properties of the insulating material but
departments to replace boilers and install
their doctor or be admitted to hospital
also on the ‘real life manner’ of
renewable technologies in a retrofit
than those living in damp homes.
• Biological decomposition
well-insulated and adequately ventilated
Fundamentally the effectiveness of CWI
depends not only on the ‘theoretical’
26
Cavity Wall Insulation in Northern ireland
Mount Eagles
Problems with inefficient cavity wall insulation isn’t exclusive to our older housing stock.
The Mount Eagles Estate in Belfast is, unfortunately, typical of many new-build estates
where there are problems with poor heat retention, poor air circulation and damp
Background
The Mount Eagles Estate in West Belfast
consists of approximately 600 homes
built from 2000. The Mount Eagles
Ratepayers Association (MERA) have
reported many issues with the build
The complaints of the ratepayers
many cases – has resulted in damp and
association generally related to comfort
mould on internal walls.
and health matters and resulted in a
number of professional property surveys
being carried out between February and
May 2013.
The initial findings led to the Centre for
Sustainable Technologies at the
University of Ulster being engaged to
specifically investigate the performance
quality of the homes and approached
Inspections often revealed voids in the
and quality of the cavity wall insulation in
the insulation industry – and John Ross
blown fibre and loose bead in the
Northern Ireland using a house on the
from SERC – to investigate a list of the
cavities which suggests that this is a
Mount Eagles Estate as a model for
worst of the problem homes.
common problem on the estate and – in
research.
28
Cavity Wall Insulation in Northern ireland
Mount Eagles
Summary of findings of
initial 25 houses
In summary
All 25 houses have underperforming
25 houses were surveyed using cavity
cavity wall insulation and there is clear
bore holes for boroscope inspection,
evidence of poor standard of fill and
thermal imaging and photography as well
breakdown of some of the materials
as recorded comments from the home
used. There was further evidence of
owners. The surveys were carried out
wasted energy heating the environment
over a period between February 2013
rather than the living spaces within the
homes. The inspections showed
and May 2013.
compaction and levels of degradation
with most fibre fill insulation with some
The findings:
Wet fibre
homes showing a slump in the cavity of
up to one meter.
• 25 houses included:
14 semi-detached and 11 detached
• Four had evidence of wet sparse
properties.
fibre which was not to the required
There was also clear, undeniable
• All 25 were built in 2001 in
density with voids present.
evidence of damp and aggressive mould
different streets in Mount Eagles.
• One had virtually no fibre in one
growth in what are relatively new Mount
• All 25 home owners said their.
gable wall.
Eagles homes.
home was hard to heat.
• Four had loose bead.
• All 25 home owners said their
• All four had evidence of voids.
All 25 home owners interviewed said
home cooled down rapidly when the
their homes were never as warm as they
heating was turned off.
would like and the heat would be lost
• Three residents wear outdoor
very quickly after turning the heating off.
clothing inside the house to keep
Thermal images showed many hot spots
warm.
on external walls with heat loss obvious.
• One house had had an insulation
top up but was still hard to heat and
Finally energy bills were requested from
cooled down rapidly when the
some of the homes affected and they
were found to be highly expensive in
heating was turned off.
comparison to what would be
acceptable
Insulation
levels based
on modern
• 21 had blown fibre.
• 17 had evidence of sparse fibre
Loose bead
domestic
which was not to the required
density with voids present.
UK
Evidence of Mould
home costs.
• 10 houses had evidence of mould,
with nine having mould in more than
one room.
• Eight houses with mould were
insulated with fibre.
• Two houses with mould were
insulated with loose bead.
• One house was found with no
mould.
However it was discovered that a
dehumidifier was in constant use to
Sparse fibre
Cavity Wall Insulation in Northern ireland
keep moisture levels down.
Mould on kitchen and bedroom walls: 76 Mount Eagles
29
Mount Eagles
SAMPLE SURvEy
47 Mount Eagles Drive,
Belfast
47 Mount Eagles Drive was surveyed on
7th February 2013 and the results clearly
demonstrate that the EPC done on the
property in October 2009 was
inadequate and not an accurate
reflection of the energy performance of
the property.
The detached property was built in 2001
with brick external walls and insulated
with blown fibre. The residents reported
that the house was cold and cooled
down very quickly once the heating is
switched off. They also reported having
47 Mount Eagles Drive
to wear outdoor clothing to try and keep
warm.
cavity to the right of the property and in
density to allow it to work in accordance
The boroscope survey of the property
other places the fibre while dry was
with its manufactured install
indicated that the fibre was wet in the
sparse and therefore not of sufficient
specification.
30
Cavity Wall Insulation in Northern ireland
Mount Eagles
Wet fibre in the cavity to the right of the property
What did the EPC say about
47 Mount Eagles Drive?
Elsewhere fibre was generally sparse
Without the benefit of an internal
However, this same spend would largely
boroscope examination, the EPC survey
cover the cost of removing the existing
of 47 Mount Eagles Drive in October
underperforming cavity wall insulation
As detailed on p.11 of this report, in the
2009 gave the property a band ‘C’ - 71
and replacing it with high performance
chapter: ‘House Surveys’, an EPC rating
rating. It was stated that the property
bonded bead; a measure that we feel
is designed to provide a measure of a
had the potential to achieve a 76 rating
sure would have a more positive impact
building’s overall energy efficiency
(still band C) if some energy efficiency
on the property’s fuel economy and lead
calculated in accordance with a national
measures were carried out. We feel that
to a truer and more accurate band ‘C’
methodology that takes into account
this EPC rating was inaccurate.
(71 rating).
The cost of the remedial work (loft
The upgrade of cavity wall insulation is a
factors such as insulation, heating and
hot water systems, ventilation and fuels
used. The average rating for a house in
insulation, energy efficient bulbs and new
more cost-effective energy efficiency
Northern Ireland is band E (rating 50).
boiler) was approximately £2,500.
measure for 47 Mount Eagles Drive.
Tightly packed:
bonded bead,
the ideal cavity wall
insulation system
Cavity Wall Insulation in Northern ireland
31
Mount Eagles
University of Ulster Report
As a part of this study, fieldwork was carried out on
properties on the Mount Eagles Estate by the Centre for
Sustainable Technologies at the University of Ulster*.
Houses on the Mount Eagles Estate
allowed to dry was refilled with bonded
were chosen for testing by the University
bead by the 18th March.
of Ulster as the residents association had
reported that many of their members
performance due to the installation of
bonded bead was in the range 21% to
39% depending on the sensor location.
The quantitative findings have been
bills, houses that continually feel cold,
University of Ulster
Conclusion
the house residents who noticed a step
mould growth on internal walls and
Following the initial inspections and as
change in the temperature and thermal
were complaining of excessive energy
damp spots on internal walls.
Sample case study
The sample case study property was
backed up by a qualitative analysis from
part of the UUJ testing, remedial action
comfort conditions in the house.
took place in two of the homes with the
The desk based research has identified
existing fibre insulation being extracted
that high performance thermal envelope
and replaced with high performance grey
and fabric based solutions that promote
bonded bead.
U-value assessed prior to removal of the
energy efficiency and prevent heat loss
have been shown to significantly reduce
existing insulation and subsequent to the
The UUJ report concluded:
the capital cost of energy running costs
retrofit of bonded bead cavity wall
“The in-situ U-value measurement study
in the home. The studies and white
insulation.
demonstrated the problems associated
papers highlighted in the research
with the variability in thermal
support the theory that cavity wall fibre
The approach taken made use of
performance of fibre insulated cavity
performance is inextricably linked to U-
ISO9869 – a standard which gives
walls.
values which are in turn strongly
guidance on measuring U-values – using
This would validate findings in the
correlated to the incidences of cold
small heat flue meters and infrared
literature that would suggest similar
homes.
thermography to ensure the study was
issues. The reasons for this variability
The precise effectiveness of cavity wall
representative.
can be wide ranging from poor fill
insulation depends not only upon the
techniques to fibre degradation.
theoretical properties of the insulating
The study took place between 1st and
When the fibre was extracted and
material but depends also on the manner
26th March 2013. The extraction of the
replaced with bonded bead insulation
of installation and on the environmental
fibre took place between 11th and 13th
the variability decreased significantly. In
conditions which the insulation is
March, and the cavity having been
addition the improvement in thermal
subjected to.”
Thermal imaging:
Fundamental to fully
analysing the condition
and volume of
cavity wall insulation
*Details of the full survey are available on request
Cavity Wall Insulation in Northern ireland
33
Mount Eagles
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si
th
o
nn
the difference
There has bee
have no idea
ly
al
re
u
Yo
r.
fa
se. Myself
the morning so
eat in the hou
h
e
th
to
e
u
d
the better.
s and colds
ctions we get
chest infection
fe
in
ss
t
le
es
e
ch
av
h
d
ll
an
we’
less colds
t and when
Hopefully now
hen I went ou
matic and the
w
th
ay
as
d
e
to
ar
ff
r
o
te
g
h
aug
the heatin
e less
and and my d
will probably b
duce too. I had
ill
re
b
ill
g
w
tin
s
ill
ea
b
h
g
y
eatin
d layers
delighted. M
I’m sure my h
d that coats an
m house I was
te
ar
le
p
w
m
a
co
to
r
as
o
o
w
d
this work
pensive.
I walked in the
e point before
getting too ex
th
as
to
w
g
g
tin
tin
et
ea
g
h
was
ld and the
than usual. It
se it was so co
au
ec
b
d
se
u
e
b
e is having
would have to
every day. Sh
s
fit
g
n
ki
ta
n
the cold
o has bee
re epilepsy wh
amage. Due to
ve
d
se
in
ra
ith
b
f
w
o
r
te
h
rm
g
ill be able to
have some fo
Mary has a dau
y say’s she w
mily and may
ar
fa
M
er
w
h
o
N
g
.
in
is
ad
n
g
e to thank
ed with her d
problems reco
d has asked m
ary’s but resid
an
r
M
te
in
u
p
ed
m
ay
co
st
ly
ately get
y can’t use a
she never real
to afford to priv
of respite. Mar
le
it
ab
b
n
a
ee
ad
b
d
e
er
h
s would hav
stay and give
n. Neither of u
io
at
tu
si
er
h
g
vin
you for impro
enough.
n’t thank you
ca
I
e.
n
there
o
d
rk
o
this w
y home when
m
m
o
fr
n
ke
n in total ta
ly in a bad
ags of insulatio
b
n
ve
se
areas and real
ly
n
in
o
p
e
er
am
w
d
e
as
er
th
problem.
insulation w
It’s ridiculous
d to sort this
. The previous
ee
0
n
2
ly
t
u
al
o
re
ab
s
n
er
ak
ee
see
should have b
houses. I can
ed. Decision m
ck
ld
o
co
sh
y
el
as
w
em
d
tr
e bags an
ere
d living in ex
state. I seen th
sity. I know th
fuel poverty an
er
iv
in
n
y
u
sl
e
u
th
rio
m
se
o
estate are
their
e readings fr
People in our
work done to
aving to get th
is
h
th
t
u
g
o
tin
ith
et
w
g
ly
e
immediate
enough to b
the difference
anyone lucky
r
fo
is!
t
en
m
ve
impro
ity to resolve th
an
n
u
e
b
m
m
ly
ite
co
in
y
ef
m
will d
on helping
focused now
lly
ta
to
I’m
.
es
solution.
hom
this innovative
ss
ro
ac
e
m
glad we ca
d work. I’m so
ar
h
e
th
l
al
r
fo
Thanks again
Regards,
ERA)
Orla McCabe
Association (M
s
er
ay
ep
at
R
Mount Eagles
34
Cavity Wall Insulation in Northern ireland
Mount Eagles
What now for Mount Eagles?
Mount Eagles Residents Association (MERA) have been very active in attempting to solve the problem
on their estate with poor insulation that has led to comfort, health and economic issues.
MERA met Minister Nelson McCausland
“Having spoken to the surveyor for
on 29th April 2013 to discuss the issues
the site back in 2001 and from my
they have been having on the Mount
own experience of working on the
Eagles Estate.
current Mount Eagles development,
receive the allocation of funding to carry
Unfortunately the Department for Social
we have no reason to suspect that
out a pilot project or ultimately to receive
Development (DSD) funds only two
the insulation would not be installed
government-backed grant funding to
schemes that are aimed at improving the
or installed incorrectly”.
remedy the defective cavity wall
Replacement Scheme and the Warm
We believe that the results of the 25
redeemable through savings to the
Homes Schemes.
houses surveyed certainly contradict this.
health service alone.
energy efficiency of homes: the Boiler
Best solution
The best solution for the residents of
Mount Eagles would be for the estate to
insulation. The outlay should be
Only a small number of homes on the
Homes in Mount Eagles which are to be
The good news for Mount Eagles
estate meet the eligibility criteria under
rented or sold now require an EPC and it
residents is that there is now an
the Warm Homes Scheme.
is assumed in the software calculation of
affordable, approved BBA (British Board
The Boiler Replacement Scheme – even
the energy rating of the houses that the
of agreement) solution to remove the
if some of the properties who are on
insulation is assumed to be up to
existing underperforming cavity wall
their third boiler in just over ten years will
scratch and performing. 47 Mount
insulation and have it replaced. The UUJ
qualify – will not solve the problem with
Eagles Drive shows that this is not the
report indicates a thermal improvement
heat retention. A new boiler should only
case.
be government-funded and supplied to a
property that is properly insulated.
between 21% and 39% when this was
carried out at 39 Mount Eagles Drive.
The residents of Mount Eagles eagerly
anticipate the findings of an investigation
Topping up underperforming insulation is
currently being carried out by the
not an option. There is no approved
Northern Ireland Housing Executive into
certified process to carry this out. The
Building control
requirements
the performance of cavity wall insulation
only option is extraction of the problem
MERA contacted Lisburn Building control
in Northern Ireland. These findings will be
insulation and then refilling the cavity with
in 2012 who confirmed that checks
published in 2014.
carried out on the Mount Eagles Estate
high performance grey bonded bead.
This solution is available for whole house
at the time of build met with statutory
Previous Finance Minister, Sammy
requirements. These did not in 2001–
Wilson had agreed to look at the
and still do not – have the installation of
statutory checks that take place within
Finally the testimonial letter from Orla
insulation as a statutory requirement.
building control and also at the defects in
McCabe (opposite) aptly sums up not
the EPC reports. A motion calling for a
only the problems and the solutions for
“
or a problem wall within a house.
Correspondence from Lisburn Building
debate has been listed in the Assembly
Mount Eagles but also the wider housing
Control (dated 19th December 2012)
in regards to cavity wall insulation in
stock in Northern Ireland and the focus
states:
NIHE properties.
of this report.
The good news for Mount Eagles residents is that there is now an
affordable, approved BBA (British Board of Agreement) solution to remove
the existing underperforming cavity wall insulation and have it replaced
Cavity Wall Insulation in Northern ireland
35
Recommended solutions
BBA approved Cavity Wall Insulation systems offer costeffective solutions to increase energy efficiency and
reduce fuel poverty in all homes across Northern Ireland
A solution for what?
SOLUTIONS FOR gREATER FUEL ECONOMy
The consequences of having underperforming cavity wall insulation are not
PROBLEM
STATE OF CAvITy
SOLUTION
Heat loss, cold
and/or damp
Empty
BBA approved
standard fill
Heat loss, cold
and/or damp
Partially filled
indicate underperforming insulation:
BBA approved
partial fill
• The home is hard to heat
Heat loss, cold
and/or damp
Dirty/damp/filled
but not performing
BBA approved standard
extraction & refill
unique to any one type of insulation and
can be attributed to a multitude of
factors. However it is normally one or
more of the following pointers that will
• The home cools quickly when the
heating system is turned off
• Mould and/or excess
condensation on windows, walls
Several members of the Northern Ireland
Insulation Industry have been working
closely with the Centre for Sustainable
Technologies at the University of Ulster
and in a report entitled: “Investigating the
performance and quality of cavity wall
insulation in existing domestic dwellings
The starting point
The Starting point is always the survey.
As was clearly demonstrated earlier while
Where the cavity is empty and suitable
discussing the limitations of the surveys
for cavity wall insulation then the solution
carried out for the Housing Condition
is to install a standard BBA approved
Survey 2011 and all EPC reports, it is
system. According to the Energy Savings
fundamental that a physical inspection of
Trust (EST):
the cavity is carried out by a trained
surveyor to establish whether the cavity is:
in Northern Ireland” have identified
several reasons for older properties
• Empty
performing less well.
• Partially Filled with Board
• Already Filled with an insulation
The Insulation industry has developed
Empty cavity:
Standard fill solution
product but not performing
two affordable, BBA (British Board of
“Cavity wall insulation is the single
most cost-effective low risk energy
efficiency measure available for the
existing housing stock, after loft
insulation. It can be installed without
major disruption to occupants and it
needs no maintenance”
Agrement) approved solutions, to
improve houses with existing insulation.
Houses with an existing insulation board
can now be topped up or partially filled
and houses with problem fibre, foam,
bead or rubble can now have it totally
extracted to allow for replacement with a
modern and efficient insulation system.
The improvement in thermal performance
can be anywhere between 20% and
40% as was reported by the University
of Ulster.
36
Fully filled cavity with bonded bead
Cavity Wall Insulation in Northern ireland
Recommended solutions
Partial fill solution
in a very high proportion (about 95%) of
cases that the partial fill was not pressed
against the inner leaf of the wall. Gaps
What is partial fill?
occurring at corners allowed for air to
Partial fill was the preferred option to
circulate around the insulation.
improve thermal performance when
building regulations required insulation
post 1980.
Another study of partially filled cavity
walls showed that the U-value can be
altered substantially when air is able to
Thermal imaging showing heat loss through a void
Partial fill cavity insulation is only
circulate in the cavity around partial filled
achievable during construction of the
board.
This system can also be used to
In: The influence of natural convection on
eradicate issues of damp and mould in
the thermal quality of insulated cavity
houses with only partially filled cavities.
external walling. Partial fill must be rigid
or semi-rigid to be fixed to the inner leaf.
construction. Building Research and
Why original partial fill
underperforms
Practice, CIB, 1990, Lecompte reported
Due to the complexity of the process,
that where there is a gap of 10mm at the
the quality of the survey is deemed
top, bottom and sides of insulation
critical and BBA require the survey to be
Fundamentally the effectiveness of CWI
board the U-value can rise by over 90%
at a level over and above that carried out
depends not only on the ‘theoretical’
leading to a near doubling of the wall’s
for conventional or standard installations
U-value.
with three boroscope inspections of the
properties of the insulating material but
cavity required for each elevation. These
also on the ‘real life’ manner of
installation and the environmental
physical boroscope inspections enable
insulation board and partially filled
The industry BBA
approved partial
fill solution
insulation board and are often the result
Cavities that were built with rigid or semi-
used when necessary to identify voids or
rigid board fixed to the inner leaf during
gaps.
conditions that the material is exposed
to. Voids and gaps are major issues with
of poor workmanship onsite.
the trained surveyors to ensure that only
properties suitable for this system are
upgraded. Thermal imaging can also be
construction can now be upgraded with
In their publication: Cavity Walls with high
BBA approval to a full fill cavity using
insulation quality: Performance prediction
high performance grey bonded bead.
Not only is the survey more complex
than that for a standard cavity fill but
there are additional install requirements
using calculation procedures and field
The hard to heat or cold house will
to ensure adequacy of fill and to ensure
refer to studies of partially filled cavity
therefore benefit from higher levels of
that the existing board is not damaged in
walls in Belgium where it was observed
thermal insulation.
any way.
testing, IBEPA 1999, Hens and Janssens
Where the board is poorly fitted (usually by a bricklayer) and gaps are present this allows cold air to circulate around the insulation
38
Cavity Wall Insulation in Northern ireland
Recommended solutions
What is cavity extraction?
system approved by the BBA.
When cavity wall insulation
underperforms, the only solution
It was vital to have a system recognised
sanctioned by the BBA is a total
and approved by the BBA to
extraction of the inefficient insulation
demonstrate that industry meets the
material before refilling the ‘clean’ cavity
highest standards.
with a BBA approved Cavity Wall
Insulation system.
Cavities can be cleared of blown fibre,
foam, blown bead and rubble under the
BBA process. Cavities cannot be cleared
of fixed rigid or semi rigid board.
How does cavity
extraction work?
Houses with problem fibre, foam, bead
or rubble can now have it totally
extracted to allow for replacement with
an efficient Cavity Wall Insulation system.
Why can’t we just
top up old insulation?
The topping up of any cavity wall
insulation is not recommended and
where defects are identified there is no
suitable system with which to ‘top up’.
Why do installers need
to be BBA Approved?
The UUJ report concluded that:
The old insulation material is broken up
and then sucked out of the cavity by a
specially developed
Extraction holes ready for the process
machine which can
separate the insulation
material from any rubble
for disposal.
Extraction and refill (using
a standard BBA approved
system) for a standard
three-bed semi-detached
“The precise effectiveness of cavity
property takes one to
wall insulation depends not only
three days. There is no
upon the thermal properties of the
mess, fuss or disruption to the
insulating material but crucially on
household.
The Mount Eagles
Estate extraction
The process can be used on a whole
The photographs above show the
Bags of fibre removed from the property
at Mount Eagles
the manner of the installation”
This is why the Insulation Industry
house or problem single wall and no
number of holes that are drilled to allow
support the use of a cavity extraction
further maintenance is required.
access for the airline.
Extraction Machine
Cavity Wall Insulation in Northern ireland
Extraction in Downpatrick
39
Benefits of a retrofit programme
Over the last few years, there have
been many independent research
projects carried out throughout
Europe investigating the benefits of
a major retrofit programme in
domestic housing. As a result of
these findings many EU countries
have now classified these projects
as essential infrastructure
improvements and have funded them
accordingly.
The major benefits of
energy efficiency
Copenhagen Economics on behalf of the
If householders have to spend less
the three major benefits of energy
on energy they are then able to spend
efficiency as energy savings, health
more on other products and services.
benefits and increased economic activity
and estimate that gross annual
investments of E41 to E78 billion per
year in the EU could bring on on-going
issue and be a key driver of what could
The economic benefits to Northern
be a major programme of social and
Ireland of a major programme of
energy policy (with huge impact on health).
energy retrofit with insulation as a
primary measure are twofold:
October 2012: “Evaluating the Economic
Stimulus of Investing in Energy Efficiency
Cambridge Econometrics concluded that
benefits to society via health, job
creation and the economy where
spending less on energy means the
public can spend more on other goods
1I
riding policy issue.
Several studies suggest that not only
does energy efficiency retrofit create a
high number of local jobs but also
Investing in energy retrofit upgrade
in Northern Ireland, especially in
fuel poor households, will have a
similar or more positive macro-economic
Measures in Fuel Poor Homes”
At this higher macro-economic level the
and services and should be the over-
The state must take a major role in this
In a report commissioned for the UK
projects such as building roads.
Renovate Europe Campaign summarise
annual returns of E104 to E175 billion.
market by the Energy Bill Revolution in
alternatives like cutting VAT, reducing fuel
duty or investing in capital infrastructure
impact than the equivalent stimulus
a national energy retrofit programme
package either through increases in
would deliver not only energy efficiency
government current spending or
replenishes national budgets. The return
for each E1 of public money invested
can be E5, in some cases within the
same financial year.
2
A
An energy retrofit and insulation
upgrade scheme in Northern
but major economic, social and
government capital spending. This
environmental benefits.
should be treated as a priority part of
infrastructure and capital strategy and
management, and leave houses energy
These benefits included boosting
consolidated in its funding and co-
efficient. A focus on energy efficiency
economic activity and tax revenues,
ordinated in its delivery.
Ireland will create hundreds of
sustainable jobs from low skilled to
investment will create “green jobs”
primarily in the hard hit construction
creating jobs in the hard hit construction
sector, reducing greenhouse gas
Investment in energy retrofit and
sector, as promised by the Executive’s
emissions, providing consumers with
insulation will substantially increase the
Economic Strategy. Further jobs will also
savings on energy bills, tackling fuel
energy efficiency of the existing Northern
be created in ancillary businesses which
poverty and creating healthier and
Ireland housing stock which is a vital part
service this sector.
warmer living environments.
of the economy’s infrastructure.
BENEFITS OF A RETROFIT PROgRAMME
No public
finance effect
Direct
effects
Public
finance effect
Energy savings
Reduced energy
tax income
Reduced outlay
on subsidies
Indirect
effects
Effects on
the economy
40
Health benefits
Increase
economic activity
An insulation upgrade scheme or energy
Cambridge Econometrics
efficiency retrofit programme will
and Verco’s research (“Jobs,
encourage job creation and economic
growth and warmer homes.
growth particularly in the short term. It
Evaluating the Economic
has other advantages. It is ‘shovel
Stimulus of investing in
ready’– fast to mobilise and will stimulate
energy efficiency measures in
economic activity and employment in all
Fuel Poor Homes”) shows
areas of Northern Ireland. As it employs
that an energy efficiency
workers in construction and allied
programme is a more
sectors where there is surplus capacity, it
effective way to stimulate the
is therefore less likely to have a negative
economy – compared to
impact on alternate economic policy.
Cavity Wall Insulation in Northern ireland
Regional strategy
with local delivery
Any such scheme could be delivered
through council led local economic
NERI examines how a mass retrofitting
“Although the rate of fuel poverty in
scheme could be established in Northern
Northern Ireland reduced between
Ireland and when discussing investment
2009 and 2011 to 42%, reducing it
in retrofitting states:
further remains a very difficult
development frameworks. In other words
“the most common example of this
it can be a regional (N Ireland) strategy
is additional insulation”
with local delivery.
In the same way that Northern Ireland
can establish itself as a high quality
tourist destination or have a world
leading screen industry we believe there
is an opportunity to establish a highly
The American Council for an Energy
efficiency. It is these SMEs that are the
employment across the province.
The Nevin Economic Research Institute
(NERI) report entitled: “Policy Options for
Investment in Infrastructure in Northern
Ireland” Jan 2013, seeks to highlight the
infrastructural investment required in the
Northern Ireland economy over the next
number of years in the context of ongoing economic stagnation and high
unemployment.
The report’s broad sector wide proposals
are supplemented by specific proposals
in the area of energy retrofitting which
the report identifies as a key measure to
upgrade the stock of buildings in
Northern Ireland. The report suggests
that with energy retrofit:
and real household incomes are
falling. Improving the fabric of
buildings can ameliorate the impact
sheet entitled “How does Energy
of fuel poverty significantly, but
Efficiency Create Jobs” examines how
cannot eradicate it altogether.”
energy efficiency impacts employment
and creates jobs.
will ultimately benefit every single person
organisations that will create wealth and
that energy prices are to remain high
Efficient Economy (ACEEE) in their fact
skilled and motivated retrofit industry that
living in Northern Ireland through energy
challenge in the short term, given
Energy efficiency
creates jobs
Health gains from
warmer homes
The Marmot Review Team (2011)
collated studies concerning the health
impacts of cold homes, and concluded:
Efficiency works redirects funds away
from less labour intensive sectors of the
“the evidence shows the dramatic
economy in order to support greater
impact that cold housing has on the
overall employment.
population in terms of cardiovascular and respiratory morbidity
On average $1 million spent in the US
and on the elderly in terms of winter
economy supports approximately 17
mortality. It also highlights the stark
jobs (including direct, indirect and
effect that fuel poverty has on
induced jobs). Investments in specific
mental health across many different
industries will support greater or fewer
groups, while also having an impact
jobs depending on the industry.
on children and young people’s wellbeing and opportunities… once the
For example where manufacturing
trade-off issues for at-risk
supports 14 jobs per $1m, an
households are addressed, energy
investment in a more labour intensive
efficiency interventions always bring
sector such as retrofit will create
multiple health and environmental
construction jobs, which supports
gains”.
approximately 20 jobs per $1m.
These gains were quantified in a
In addition to economic benefits, a major
Northern Ireland cost-benefit analysis
“the impact on unemployment could
retrofit programme is likely to bring
(Liddell, 2008b), which concluded that,
be significant, it is estimated that
significant social benefits, particularly in
for every £1 invested, 42 pence was
every £10m invested could create up
combating Fuel Poverty and the health
returned in quality of life gains.
to 330 jobs in Northern Ireland”
problems associated with cold damp
and continues:
“...even with severely constrained
housing.
Finally, the UK has a statutory obligation
to reduce CO2 emissions by 80% below
The Housing Executive acknowledge this
1990 levels by 2050 (The Climate
budgets, there are still options open
in their report “NIHE Market Review
Change Act 2008). It is expected that
to boost investment and grow our
2013-2016” when discussing the
emissions will be cut by 50% over 1990
economy”.
strategic perspective, and state:
levels by 2023 to 2027.
Cavity Wall Insulation in Northern ireland
41
Conclusions
We believe this report highlights that the
The samples presented in this
Every day local installers receive calls
standard of insulation within the
publication are but a few of the over one
from home owners and tenants
Northern Ireland housing stock may be
hundred homes we surveyed,
complaining of excessive cold and damp
overstated.
comprising of a wide range of house
within their properties. This is a situation
There can be little doubt that poor levels
type, age and geographical location
which can and must be addressed.
of insulation is a contributory cause of
around Northern Ireland.
We would like to make the following
the extremely high level of fuel poverty in
The problems we found however, were
recommendations to Government and
the province.
invariably common to all.
our elected representatives:
• Further work should be commissioned to
• The bi-annual House Condition Survey
identify the quality and effectiveness of
carried out on behalf of the government by
insulation within our homes.
Northern Ireland Housing Executive should
Since we began this exercise we are
encouraged to hear that the Northern Ireland
Housing Executive has begun a survey of the
wall insulation on a sample of 300 of their
houses.
include a thorough wall and loft inspection.
government policy on Decent Homes and
tackling Fuel Poverty is reliant on the
accuracy of this information.
• Both partial fill of cavity walls and fibre
We have passed the results of our sample to
extraction and refill should be added as
them for consideration.
measures on all government funding for
insulation provided the appropriate
• government should address the current
flaw in the EPC system and include a
certification is in place.
boroscope inspection of the wall and a loft
Fabric first
inspection.
There should be an emphasis on insulating all
properties efficiently in the first instance.
This would increase the cost of the inspection
marginally, but without this taking place we
believe the rating system used is worthless.
• government should ensure that an
inspection of cavity walls becomes a
Whilst boiler scrappage schemes
can be effective, if the property is
not properly insulated the occupier
just ends up heating the street.
statutory obligation for Building Control on all
• The scale of the problems we have
highlighted in this report is significant.
new build property.
A working group should be established to
progress a major retrofit programme.
• Overtures should be made to NHBC to
The benefits of this sort of infrastructure
include cavity wall insulation in their 10 year
spend are well documented and outlined on
guarantee.
page 40.
Thank you for reading this document. If you would like any further information or to discuss it
further, feel free to contact: Bill McCandless at bill.mccandless@energystoreltd.com
42
Cavity Wall Insulation in Northern ireland