The UK’s first social housing development to achieve the European PassivHaus standard, effectively offering near-to-zero carbon living, features a triple-glazed system from Internorm.
The scheme at Wimbish near Saffron Walden in Essex has been built for Hastoe Housing Association by Bramall Construction. Parsons + Whittley was the architectural practice responsible for bringing together a series of compatible technologies to achieve the required maximum space heating consumption figure of 15 kW hours per square metre per year. Tenants are paying gas bills as low as £5 per month.
In addition, while building regulations allow an air leakage level of 10 cubic metres per square metre of building envelope per hour, tests on the 14 new homes at Wimbish measured just 0.45 m3/m2/hr on average. The air tightness of the Internorm frames themselves, and the way they are sealed into the SIM (super-insulated aircrete masonry) walls using Tremco illbruck tapes and foam, was therefore critical.
The Project Architect, Chris Parsons, reports: “A value engineering exercise enabled us to switch the specification to the Internorm windows. The result was the U-values we required at an affordable price. In terms of air leakage, the final figure we achieved was just 0.45 air changes an hour, which is even better than the 0.6 m3/m2/hr set as the minimum for PassivHaus.”
The installer, Dynamight Products, has also been involved on the creation of several other PassivHaus structures around the country, including a community centre in Powys, a commercial office building in Kent, and two of the self-build projects featured on Grand Designs.
Thomas Froehlich, who founded Dynamight Products, comments: “We are an Internorm Partner. Internorm is well known across Europe as a PassivHaus solution. Our success lies in our involvement with most of the UK’s early PassivHaus projects, helping to achieve the U-values needed, and also the outstanding quality. Internorm trains its partners and their fitters to European Standards to ensure that they provide a high quality service.”
Parsons + Whittley is currently involved in the design of 14 more PassivHaus properties for the same social housing provider at Ditchingham in Norfolk where Internorm windows are again expected to be specified.
