Affordable Sustainable Housing for Exeter
"Not a day goes by when I don't say 'I like living here' "
"This development has incorporated sustainable technologies into an innovative design which has assisted Exeter City Council in meeting its housing needs by providing the local residents with high quality affordable housing whilst reducing the impact on the environment for the life of the building."
For Exeter City Council; £450k contract value; completed 2011
Rowan House at Sivell Place, Exeter are among the first social housing accommodation in the UK to be built using the Passivhaus method for an apartment development.
When the client, Exeter City Council, was offered a funding opportunity by the HCA to develop council housing in Exeter, it was decided to use this chance to provide exemplary, affordable housing, built to the highest standard of sustainable construction.
The site is situated within a Conservation Area in Exeter with a Grade II listed building on the adjacent site to the west and a locally listed building to the east that has recently been converted for residential use.
The primary design objectives were:
- to develop a sustainable and healthy affordable housing scheme to meet Code 4 of the Code for Sustainable Homes and the Passivhaus standard.
- to achieve a contemporary interpretation of vernacular forms that is respectful of its residential context in terms of scale and massing, and that will be attractive to ‘down-sizing’ tenants.
- to provide down-sizing units throughout, to be fully accessible in accordance with Lifetime Homes Standards.
To meet the stringent Passivhaus standard it was required to achieve exceptional levels of air tightness with the air permeability target as low as 0.3 cbm/sqm/h. This, together with high levels of insulation, high performance windows and doors, thermal bridge free detailing and the use of a more than 90% efficient mechanical ventilation system has reduced the overall heating demand to a minimum so that a traditional heating system was not required.
Achieving the Passivhaus standard was only possible through the combined effort of the design team developing the air tightness strategy and detailing, the site management team and builders for implementing this strategy and finally the client for their commitment and passion to deliver an outstanding, exemplary housing scheme. Purely through passive design elements Rowan House will use approximately 90% less heating energy when compared to a standard UK building (if built to current Building Regulation requirements). In other words Rowan House could be heated by the equivalent of 1.5 litre of heating oil, i.e.15 kWh of thermal energy per sqm per year, or 60p per sqm per year (based on a price for heating oil of 40p a litre), making it truly affordable for its future tenants without compromising on comfort or indoor air quality.
Key qualities of the design:
- The design seeks to achieve a contemporary interpretation of vernacular residential forms. The reduction in ridge height, either side of the central building element, breaks down the mass of the building giving the appearance of a collection of smaller units. The resulting arrangement is sympathetic to the surrounding residential area both in scale and detail.
- The quality of materials and subtle fenestration will offer residents a sense of a place with an appropriate ‘quiet’ character within the conservation area which they can take pride in over the long term.
- Code 4 of the CSH
- Fully compliant with Lifetime Homes Standards
- All occupants gain private gardens, designed using Permaculture principles
- Building design based on the Passivhaus method will ensure minimal heating requirements and greatly reduced carbon emissions.
- Solar Panels serving each individual unit will further reduce the energy demand for domestic hot water
- Designed to meet best practice daylight levels in accordance with the requirements of the Code for sustainable homes.
- 100% energy efficient light fittings throughout
- Compliant with Secured by Design
- Independently assessed under the Building for Life standard with a final score of 18.5 out of 20
- Considered Constructors Scheme rating of 37.5 out of 40
- Through the use of low water use fittings the water consumption was reduced to less than 80 litres/person/day
- Rowan House is currently being assessed to become Passivhaus Certified
The flats also have a number of features designed to improve the health of their tenants including the use of ceramic floor tiles to reduce dust mite infestation, minimal volatile organic compounds (VOCs), no PVC throughout (including any pipes and wiring) and radial electric circuits to reduce electro-magnetic radiation (EMF).
This building shows that we can defeat fuel poverty and combat climate change at the same time. Rowan House will be amongst the most energy efficient and healthy homes in the UK. The super insulated buildings use a fraction of the energy of traditionally constructed new buildings and will allow for extremely low running costs.
There will soon be a time when we all wonder why we ever thought heating our homes with valuable and scarce fossil fuels was a sensible thing to do.