Passivhaus, Healthy Homes for Exeter City Council Tenants
The development of 6 terraced houses, including one wheelchair accessible unit, at Reed Walk, off Newport Road in Exeter, is one of 3 sites developed by Exeter City Council (ECC) to deliver high-quality, affordable, healthy, Passivhaus homes for Exeter's social tenants.
Completed in August 2015 and occupied shortly thereafter, Reed Walk is part of the second wave of council-own-build developments in Exeter designed to optimise underused sites in the city. Together with sites at Barberry Close and Silverberry Close, Gale & Snowden Architects have helped ECC deliver a further 20 family homes. G&S first introduced ECC to the concept of Passivhaus and Healthy Buildings during the first wave of Council developments in 2008.
The design of the houses utilises dense concrete blockwork walls, wrapped with high levels of external wall insulation and colourful render. The combination of high internal thermal mass, insulation, thermal-bridge-free design, and exceptional airtightness will result in excellent, stable comfort levels and very low energy bills for occupiers.
The houses tackle fuel poverty and provide exemplar living conditions with the specification of healthy building materials based on Building Biology principles featuring:
- non-toxic materials
- organic materials
- designing out the risk of dust mites
- minimising electromagnetic radiation by good wiring design and specification
- high levels of thermal comfort
- high levels of natural daylight
Air tests carried out during construction delivered outstanding results of 0.275 air changes per hour (at 50 Pa) that were well below the requisite 0.6 ac/h demanded by the Passivhaus Standard and approximately 1/30th of those required by current UK Building Regulations.
Air quality in the homes is maintained to a high standard via highly-efficient mechanical ventilation with heat recovery (MVHR), and is also achieved by the specification of non-toxic materials and finishes such as mineral paints and organic waxes.
The external colours were carefully developed to reflect natural building materials of the Exeter area such as Devon sandstone, blue lias, green marble, clay brick and Heavitree stone. Internally, a distilled palette of high-quality, robust materials accentuates simple, efficient floor plans.
Ecological landscape design strategies have been employed for the site with all communal and private garden areas designed to follow permaculture principles. Bird boxes are mounted on the building, whilst habitats for bats, swifts and insects have been installed throughout the site establishing wildlife corridors linking the site to existing local ecology.
"These new homes are sustainable, environmentally sound and offer great energy-saving features for the families living in them. But they are also providing a space for a strong community spirit to grow and develop, that will set these families in good stead in the future"
COUNCILLOR SUTTON, LEAD COUNCILLOR FOR CITY DEVELOPMENT, ECC