Housing Associations and sustainable construction. Jenny Wain. Contents:
Arches and refurbishment - Valley Road
Scheme summary
The scheme consists of the refurbishment of four inner terraced houses built about 1900. The refurbishment was carried out to a very high standard of energy efficiency, and involved the use of environmentally friendly materials. The properties were purchased in 1999, and work was completed in August 2000.
Scheme details
Arches Housing Association bought four terraced houses in the Meersbrook
and Heeley areas of Sheffield. Three were improved to very high standards
of energy efficiency. The fourth was improved to the minimum energy efficiency
required by the Housing Corporation as a ‘control’ house,
enabling comparison of monitoring results from gas, electricity and water
bills. The aim was to reduce residents’ bills by around £300.
The original houses had a basic central heating system, single glazed
windows and no roof insulation. They were heated effectively, but without
insulation the heat escaped very effectively too. The houses had an average
SAP of 46 and NHER 4.4
The environmental refurbishment aimed to provide healthier and more comfortable
homes, but not at the expense of the environment. Budget constraints meant
that ‘passive’ energy saving measures and low cost approaches
were considered over complicated and/or expensive technology.
The value of comprehensive insulation and the use of energy efficient
appliances was crucial to the scheme’s success. By keeping the approach
simple, Arches has proved that the impact on the environment can be reduced
and significant fuel cost savings made.
Environmental features
In each house the windows needed replacing.
New, sustainable sourced timber windows were installed with double glazed
low-emissivity Pilkington K glass. This glass provides a similar energy
performance to triple glazing but is much more cost effective. It cost
around £10 extra per m2; an extra £70 – 100 for a typical
terraced house. (Low emissivity windows have a coating applied to the
inner surface of the outer pain of glass. This allows the warmth of sunlight
through, but reduces heat lost through the glazing).
Insulation was needed throughout the buildings’ fabric. 200mm of
cellulose insulation (recycled newspaper) was introduced to the roof,
improving energy efficiency significantly.
The 9" solid brick external walls were dry-lined with liner board
encapsulating 52mm of mineral wool insulation. This reduced the heat loss
(U value) to a rate similar to a standard cavity wall and gave a SAP as
good as some newly built homes.
The properties were built with cellars,
and access could be gained to install 150mm of mineral wool under-floor
insulation.
Once the issues of the building envelope were addressed, other areas were
considered. Thermostatic radiator valves were added and low energy light
bulbs installed. Energy efficiency could have been further improved with
the removal of existing gas fires, however residents wanted to retain
them.
Gas condensing boilers were installed with simple heating controls rather
than state of the art programmers and controllers. Although it was recognised
that when properly programmed they can improve energy efficiency, they
can also be difficult to understand and use correctly. One house was fitted
with a condensing boiler and solar water panel to pre-heat hot water.
This improved its SAP to 97, which is far in excess of the energy efficiency
achieved in a typical standard built home.
One home was fitted with a grey water recycling system. The bath water
is pumped back to flush the toilet and reduce mains water use.
Water based paints and stains and linoleum flooring to kitchens and bathrooms
added to the environmental and healthy quality of the houses.
The refurbished houses achieved a final SAP
of 94 and annual savings in the region of £420. The ‘control’
house had a SAP of 68 and achieved annual savings in the region of £300.
Costs
The total cost to refurbish the control house was £10,500. This
includes a condensing combination boiler that proved necessary to achieve
the minimum SAP rating. The average cost to refurbish the more energy
efficient and sustainable houses was £17,500.
The Green Scheme was funded by the Housing Corporation. It is energy efficient
and acts as a test bed for green materials and ideas to show the compromises
necessary when existing stock and limited works budgets come together.
Great results are easy to enhance stock, save residents £6 a week
and benefit the environment.
Summary of energy efficiency improvements, costs and resident savings:
| Feature | SAP | NHER | Cost £ | Saving p.a.£ |
| Double glazed low E | 48 | 4.7 | 70 – 100* | 33.00 |
| Condensing boiler | 60 | 5.8 | 200 – 300* | 30.00 |
| Insulation | 94 | 9.4 | 1,600* | 310.00 |
| Thermostatic radiator valves | 50.00** | 7.00 | ||
| Low energy light bulbs | 24 – 40 | 13.00 |
Developers comments
The Green Scheme was funded by the Housing Corporation. It is energy efficient and acts as a test bed for green materials and ideas to show the compromises necessary when existing stock and limited works budgets come together. Great results are easy to enhance stock, save residents £6 a week and benefit the environment.
Further information
Developers: Arches Housing Ltd: tel 0114 228 8100