Energystore
Case Study
Partial Fill Insulation Advantages
Old Mill Dale
Dundonald, Co. Down
Prepared by John Ross MSc Research Lecturer SERC
John Ross SERC December 2013
Introduction
This case study was conducted in a before and after scenario, in response to complaints by the home
occupants, Mr & Mrs C of their home being ‘hard to heat’, cold and costly in the terms of energy running costs.
The property at is a detached 3 bedroom home in Old Mill Dale, Dundonald , Co, Down is one of large amount
of domestic dwellings within the relatively new Old mill estate boundaries.
To assess the energy loss, this was initially completed by visual means, checking the homes external fabric to
assess if any building issues were at the heart of the compliant. No building defects were obvious anywhere on
the homes externals, i.e. Cracks, missing elements etc. In line with acceptable standards a thermal audit was
conducted using a Flir 3 thermal imaging camera, with its use it’s simple to highlight areas of concern, detect
heat losses through the homes cavity walls directly into the atmosphere. This process was conducted at set
times (cold and without solar inflection, all the before thermal images were taken at 6.15pm at night) with the
homes heating fully engaged for at least one hour before the visual survey took place, in order to maximise the
fabric losses and capture them on file. The following images reflect a before and after scenario and the
information captured by the thermal imaginary, the findings from them were analysed by myself. The home
was further surveyed by Boroscope test holes to ascertain the quality of insulation, which showed issues as per
the thermal inspection. Agreed, appropriate remedial insulation repairs (partial fill treatments) were
completed in line with the latest industry recognised British Board of Agrement, (BBA) standards using Grey
ESP bonded beads to correct the energy losses.
The methodology was to assess the fabric energy losses and the cavity originally had 50mm polystyrene board
in the wall and the existing cavity has been partially fill treated with further 50mm of ESP grey bonded bead
manufactured by Energystore to BBA approved standards. From the evidence of the “after” images the visual
improvements after the insulation was assessed and remedied using partial fill techniques is considerable.
Below (Fig 1) is an example of a home really well insulated and has a uniformed blue cool colour i.e. no/little
heat loss other than around the windows.
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Fig 1 highly insulated home example, consistent cool colour
John Ross SERC December 2013
Fig 2 house front
Fig 3 house front huge energy losses
Fig 4 gable front
Fig 5 gable front energy losses red & white
Fig 6 Gable rear
Fig 7 Gable rear thermal image
John Ross SERC December 2013
Figs 8 & 9 Back gable images after treatment
Fig 10 Back Right gable (wide angle lens) Fig 11 Back Right gable before
Fig 12 Back Right gable “After”
Chimney breast
Fig13 Front gable before treatment
Fig 14 front gable “after treatment”
John Ross SERC December 2013
Fig 15 Front before treatment
Fig 16 Front “after treatment”
Thermal images
The report contains several colour infrared images which can be difficult to understand. The equipment sees
heat instead of light and automatically allocates various colours to different temperatures. For example red is
hot and blue is cold. The hottest colour being white the coldest being black. There are several factors that can
lead to misinterpretation of a thermal image. Different materials reflect energy in different ways, such as glass
or highly polished metals. Where there are materials like glass, the information recorded must be ignored, as it
is not an accurate temperature. A well-insulated roof or building in good condition should show consistent
temperatures and colours across its surface.
Summary
The initial thermal inspection showed many areas of fabric where heat loss is evident. The home is probably
best described as having been brought up to around the ‘U’ value levels equated to the 2007 Building
regulations i.e. 100 mm cavity full fill. There is room to consider that the existing high heating costs are directly
associated with the thermal issues identified in the inspection process and that the home occupants now
experience new levels of comfort within the home.
In simple terms, the outside wall should appear in the thermal image as a continuous, cool colour (Blue),
Yellow, reds, etc reflect heatloss all existing homes built to current regulation standards will emit losses due to
current ‘U’ value standards.
Visual cavity Inspection process
Five Borescope holes were drilled and inspected with a Wi-Fi Borescope linked to an iPad 2 tablet computer
running a specialised energy survey software programme (Eco Compliance). The insulation board was found to
be in good condition generally, where seen. At the front right corner, we found an un-jointed section of board
and where there was no insulation which results in heat loss. At the rear of the property we observed the
insulation board in its original wrapping, which may cause sweating but will prevent the board from insulating
properly. There appeared to be 25mm and 50mm insulation board (2 different size boards) but this is difficult
to confirm due to the state of the cavity and the limited bore test holes. Throughout the cavities there is a
clear minimum 50mm void which can benefit greatly from partial fill with Bonded ESP bead.
John Ross SERC December 2013
Recommendations
To improve the thermal comfort of the house, Energystore recommended remedial action with a partial fill of
the 50mm void (100mm cavity, existing 50mm insulated board) with grey bonded expanded polystyrene (ESP)
bead. This was completed to existing British Board of Agrement, BBA, standards by qualified and approved BBA
certified Energystore staff.
Limitation of thermal survey
A thermal image will show heat loss through the building fabric and sets out clear areas of fabric heatloss.
Thermal imaging merely shows areas of heatloss, it cannot be used to assess the amount of energy escaping
from the fabric. Each time an image is taken the camera recalibrates to give the actual temperature range
(measured in degree Celsius) at that particular point in time. Therefore each image is independent and subject
to variation due to sunlight or wind chill factors. Each image will have slight changes in temperature range as
seen on most of the slides.
The bottom of each thermal slide will have recorded the lower temperature (on the left) and the higher
temperature (on the right) for that particular image. The higher temperature, and colour associated with the
higher temperature can then identify points where heat loss is greatest.
The colours show on each slide will be between these two temperatures points.
Each image has a cross-hair, used to focus the image which helps indicate the temperature at that particular
point on the building fabric. This temperature where the cross hair is located is seen on the top left hand
corner of each thermal slide.
“Homeowners Testimony”
Roughly I use about 1800 litres of Oil a year, £60 per month Electricity (Probably less in
summer!) and about £40 per month Autumn/winter in coal.
Yes we have noted a great improvement in warmth and as you mention retention of
warmth and as such would highly recommend to anyone.
Hope this helps
Mr Coulter, Homeowner
John Ross SERC December 2013
Energy analysis
Fig 17 Source www.Boilerjuice.com Year average price of domestic heating oil Northern Ireland
Average cost 56 pence per litre energy analysis using assumptions!
1800 litres @ 56pence per litre = £1008 per annum
Coal 6 month approx. @ £40 = £240 per annum per annum
Electricity 9 months at £60 per month and 3 months at £40 = £660
Total
£1908 per annum energy cost
From the data supplied below in relation to UK average energy costs, this homes energy costs are more than
twice those quoted in the UK Housing Energy Fact File. Source: United Kingdom housing energy fact file,
Palmer J, Cooper I, 2012.
This home has provided annual energy figures around £1908 per annum. Clearly from inspections carried out
on this home and others the energy analysis for Northern Ireland homes is somewhat questionable. The
funding being provided by government departments to replace boilers and install renewable technologies in a
retrofit situation will all have questionable energy improvement outcomes if the levels of thermal protection is
ongoing at the levels we have found across many different house types in terms of size, type and locations.
The need to insulate before any other expenditure is paramount in dealing with providing comfort and low
living costs. Below is the 2011 average total heat,light and power running costs for a UK home of £21 per week
i.e. £1092 per year? The costs here are nearly two fold and the fuel prices are higher but not that much a
difference!
John Ross SERC December 2013
Fig 5 Average UK expenditure on total energy costs approx £21 p/week
John Ross SERC December 2013