First Passivhaus in the country to use traditional cavity wall construction cost £141,000 to build and will use 90% less energy for heating than average
The first Passivhaus in the UK to use traditional cavity wall construction has today received its official certification.
Councillor Julie Stewart-Turner, the mayor of Kirklees, with Bill Butcher (project leader) and Chris Herring (technical adviser) at the Denby Dale Passivhaus
The project in West Yorkshire, which Building has been following for the past 12 months in its Passivhaus Diaries, has been built by the Green Building Company and pioneers the combination of the German low energy Passivhaus method and standard British cavity wall construction and building materials.
There are now more than 10,000 certified Passivhaus buildings in the world, which typically use timber-frame construction or block work walls with external render. Cavity wall construction was chosen for the Denby Dale project in West Yorkshire because most British builders are familiar with the technique and materials could be sourced easily from any builders’ merchant. It also met Yorkshire planning requirements for a stone exterior.
Bill Butcher, director of Green Building Store, said: “The Denby Dale Passivhaus proves that it possible to build an ultra low-energy house using British building techniques and materials, at a low cost. Good simple robust design, knowledge and care in application are all that are needed to achieve Passivhaus levels”.
The three bed detached house has cost £141,000 to build and will have space heating needs of under 15kWh/m2/year meaning it will use 90% less energy for heating than the average UK house. As a result heating costs are expected to be about £75 a year.
Passivhaus design relies on a well insulated airtight building envelope and tests at Denby Dale revealed an airtightness of 0.33 air changes per hour at 50 Pa, which is about 25 times better than Building Regulations requirements.
Professor Wolfgang Feist: originator of the Passivhaus methodology and founder
of the Passivhaus Institut in Germany said: “The Denby Dale project has proven that Passivhaus design can be easily adapted to British building techniques. Airtightness is not a myth - the rules of physics are the same everywhere - and wet plaster offers an excellent airtightness barrier for cavity walls, if applied to all surfaces of external walls and connected properly at the joints”.
