Insulation installer SCIS Group has commissioned Peregrine Mears Architects to create two testbed affordable eco-homes in Hampshire, seeking to prove that such housing can still be well designed
An insulation installer has made the leap into residential construction, securing planning permission to build a pair of testbed affordable eco-homes on a site in Gosport, Hampshire.
South Coast Insulation Services Group (SCIS Group) appointed Peregrine Mears Architects (PMA) to design the three-bedroom properties, which will exploit offsite construction and passive house design principles to achieve high levels of air tightness and thermal efficiency.
Combined with the use of low-carbon tech, including air-source heat pumps and solar photovoltaics, the EPC A-rated homes are expected to cost less than £600 a year to heat and power.
According to SCIS Group, the pilot aims to prove that building affordable homes kitted out with the latest low-carbon technologies doesn’t require design compromise. Nor should they take longer to build than conventional homes.
PMA project architect Ciaran Linane said: ‘Other developers have included similar measures in homes but we're hoping to underpin it with a design-led ethos to create fresh, contemporary designed homes, not a cookie cutter approach.’
PMA’s design references the area’s garages and light industrial infills. The ground floor is constructed from brick to the height of the existing garages and the first floor and roof are clad in metal profile sheet.
The homes’ non-traditional layout positions the bedrooms on the ground floor and living spaces on the first floor, making the most of natural light from rooflights and reducing the energy needed to light and heat the property during the day.
Adopting a fabric-first approach, the homes will be built from offsite-manufactured structural insulated panels (SIPs) with a double layer of insulation to help ensure airtightness and prevent cold bridges.
The architect's SAP calculations were based on the use of the SIP system. The full wall build-up can achieve a fire resistance of 30 minutes tested in accordance with BS EN 1365-1. Assembly on site is expected to take just two-to-three weeks.
Both properties will feature mechanical ventilation with heat recovery (MVHR) and triple-glazed windows with low G values, positioned in optimal locations to boost solar gain. Elevations exposed to more direct sunlight will include 600mm-deep window reveals to enhance shading and help prevent overheating.
A saw-tooth roof design features four pitched sections with skylight windows on the north-facing side and solar panels on the south-facing side to harness maximum energy from the sun.
Other low-carbon technologies in the properties include hot water recovery/recycling, underfloor heating, and rainwater recycling.
Having an insulation company, which also now does renewable energy installations, as the developer will help smooth the process, says Linane. ‘Our client does a lot of the installation work itself and it’s able to be quite hands-on with the contractor, in terms of delivering works packages for insulation, bricklaying, timber cladding and window installation, and verifying airtightness for the building.’
Furthermore, pre-wired services are being looked at to avoid potential issues with installers ‘piercing through vapour barriers and linings’ and to ‘future-proof the house as much as possible’.
Linane says the testbed should verify whether it’s possible to deliver homes under market value, adding that the ‘quite small, largely uncomplicated site’ provides a good starting point ‘before we go on to deliver more homes on trickier sites’.