A Post Occupancy Evaluation of a low rise social housing complex
following an energy retrofit and refurbishment project 2012-2013
This presentation addresses the perceptions that an energy
retrofit and refurbishment project will meet all intended design
and function principles. The research highlights the importance
of monitoring a building post work's testing its functions and
improving research towards improved housing conditions and
affordable warmth for low income households.
By
Aidan Shannon
What is A Post Occupancy Evaluation
A POE asks the questions
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Does the building perform as intended?
Have the user’s needs changed?
What problems need to be tackled?
How effective was the project delivery?
Process from inception to completion?
What can be learned for future projects?
Housing standards a Century on ?
From Dublin’s Tenement's in the
late 1800’s to the mid 1960’s
Social Return on Investment
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65 per cent of people’s lives are spent at
home or in the near vicinity of their homes.
(Ormandy 2009)
O’Connor (2013) estimated that 39% of local
authority households are fuel poor.
low income households generally have lower
average indoor temperatures than wealthier
households.
Low indoor temperatures have been shown
to be associated with poor health and a
contributory factor to excess winter mortality
rates in Ireland, Healy (2003)
A total of 410,000 people received the Fuel
Allowance in 2013.
Utley and Shorrock (2008) have shown the
average temperature in British housing has
risen from 120C in 1970 to 17.70C by 2006,
following the introduction of central heating.
St Nathys House Churchtown Co Dublin 2014
Retrofitting Occupied social Housing
• Energy Upgrade &
Refurbishment of 28 units
• Door & Window replacement
• Pumped Insulation to cavity
walls
• Roof Insulation
• Drainage works
• Upgrade service Stacks &
Fireproofing
• Replace kitchens &
bathrooms
• Painting
• Upgrading & fireproofing of
bin-Shute
Pre-Works Conditions
St Nathy’s North elevation
Typical sitting room
Typical bathroom
Un-kept stairwell
Asbestos lined panels, single glazed
Energy Upgrading & Refurbishment
Methodology
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The BER certificate does not take into
account post-energy evaluations nor does
it take occupants behaviours into account
Energy retrofits evaluations omit the
human dimension.
A triangular approach was taken so as to
close comparisons on energy
consumption, indoor room temperatures
and occupant feedback.
Gas and Electric metre readings were
recorded over a 6 month period, for 14 of
the occupied dwellings.
Living room Temperature data was
recorded from January to February to 4
apartments.
Semi-structured interviews were
conducted with 13 of the 14 households,
of which 11 were recorded.
Delivered energy over 6 month survey period and DEAP
calculations for 1 years estimated Energy consumption kWh
St Nathys House Survey – Delivered energy over 6 month survey period and DEAP calculations for 1 years estimated Energy consumption kWh
DATA
Unit Number 2
7919
3
6010
4
8614
5
5075
8
6728
9
5549
10
3955
12
6094
17
6792
19
10022
23
7723
25
6430
27
6982
28
3830
2286
2154
1092
1099
940
235
1804
883
637
1561
1229
1871
1040
697
10205
8164
9706
6174
7668
5784
5759
6977
7429
11583
8952
8301
8022
4527
6595
6542
6567
6593
4352
4396
4308
4611
4872
8015
5475
5252
5093
7682
673
2
7268
674
3
7216
640
4
7207
674
5
7267
509
8
4861
514
9
4910
660
10
4968
363
12
4974
652
17
5524
674
19
8689
560
23
6035
442
25
5694
709
27
5802
618
28
8300
Actual delivered
energy over 6 months
kwh
Shortfall after 6
months in KWH
10205
8164
9706
6174
7668
5784
5759
6977
7429
11583
8952
8301
8022
4527
2937
948
2499
-1093
2807
874
791
2003
1905
2894
2917
2607
2220
3773
% above DEAP
calculations after just
6 months
40%
13%
34%
-15%
57%
15%
16%
28%
34%
33%
33%
45%
38% -45%
Delivered Gas over 6
month period in KWh
Delivered electricity
over 6 months
Total Delivered
energy over 6 month
period KWH
DEAP Calculations for
Gas x 1year as per
BER, certification
DEAP electric x 1 year
Unit number
DEAP -Total Predicted
Delivered energy for
1 year as per Ber
certificate
Mean % difference without units 5 and 28 = 31% delivered energy above the Predicted BER after just 6 months across 12 units
Easy log Temperature data recordings
Unit A
Unit B
Unit C
Unit D
23.05c
19.02c
19.01c
19.05c
Ground Floor 52m2
1st Floor 52m2
3rd & 4th Floor 56m2
3rd & 4th Floor 61m2
Table 1. Shows the average mean Temperatures for Sitting rooms in four of the
surveyed Apartments, from January until February 2013 & Easylog unit 10 below
Variables effecting space heating consumption
noted through the Energy survey
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External temperature
Orientation, floor level, area of external surfaces
Un-occupied units adjacent to dwelling
Time spent in dwelling
Number of occupants
Thermal conditions of unit following works
Use-ability of heating controls
Option to use multi- fuel stove
Window opening due to poor indoor air quality
Behavioural issues
Unit floor space
kWh comparisons to HDD
Semi structured interviews Findings & Feedback
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The multi-fuel stove was only used by 1 occupant of the 13 dwellings. A number of reasons
were given, “It’s too much hassle cleaning out the grate and carrying the fuel upstairs” and
“It gets too hot in the room when you have it on, even with the doors open”.
Eleven of the respondents found their new home warmer while two said there was no
change.
Drying clothes was an issue raised by 12 of the respondents, as the apartments themselves
fall well short of the DOE floor space guidelines. This may have contributed to the high
humidity levels within some of the units, leading to condensation, increasing the risk of
mould growth, and increasing the risk of health issues.
Three interviewees living on the 3rd and 4th floors pointed out that there was a draft from the
large sitting room screen on windy days. One of the households positioned their sofa so as to
avoid the draft.
11 of the respondents made reference to having difficulty understanding and reading their
fuel bills.
Acoustics levels had improved for units on the upper floor levels / public house & fire station
Only one of the thirteen interviewees paid by direct debit to an energy supplier, three paid
pay-as-you-go gas metres and the remainder of energy bills were paid in the post office.
A number of residents asked why they did not have access to the electric metre room.
Through field observations the author noted that the indoor air quality was poor in some of
the units, due to over-crowding and lack of storage space, along with cramped floor areas
taken up by furniture.
Room for Improvement
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A balance needs to be found when refurbishing low rise social housing to conform to
new thermal building codes.
A delicate balance needs to be developed to ensure energy efficiencies are realised
whilst health and well-being of the occupants are maintained.
Thermal imaging should become mandatory for pre and post retrofit energy
refurbishments
Energy literacy information and advice should be offered to all households
undergoing retrofit and refurbishment works.
Laundry room facilities and covered Clothes lines, will improve health conditions ,
floor space congestion and add to more social interaction.
Energy bills should be made easier for customers to understand.
Heating controls should be designed for ease of usability for everyone including the
elderly.
Behavioural usage patterns of teenagers and children should be researched in
greater depth.
Conclusions
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95% of the units surveyed did not meet their predicted BER after just 6 months.
Gas accounted for 84% of the delivered energy, used for space and water heating.
Elderly occupants were the lowest users of electricity even though they spend 23hrs per day in
their home.
Average indoor room temperature survey concurs with Hong (2009) following a case study in
the UK of 2,500 homes following energy retrofits as 19 c.
A balance needs to be struck when retrofitting social housing stock, rather than try
concentrate all the focus towards thermal performances, indoor air quality, is of crucial
importance to a healthy indoor environment.
The disruption caused in rehousing the residents and the need for facilities to ensure
community integration had been completely overlooked.
Appraising the reactions of the occupants by “real life” research can add as research
partners rather than objects of research.
Thermal imaging, and pre-design assessment format should become mandatory.
Currently there is too much emphasis on new developments, providing a very small
percentage of housing stock over the coming years. Addressing the houses and buildings of
today could provide vast social benefits to occupants and state.