We are delighted to announce that The Princess Royal will be officially opening the new Passivhaus development for affordable homes in Wootton Wawen. Morton Wykes Kramer Architects are the driving force and designers for the scheme, working in partnership with Warwickshire Rural Housing Association (WRHA), Bouygues UK and Waterloo Housing.
“As a practice, we pride ourselves on the forward-thinking approach of our architects. Integral to this is our belief in the importance of our continual search for new ideas and changing approaches within our profession. With an ever-increasing awareness upon the importance of sustainability and energy efficiency we have been involved in a seven-year research and development project to bring exceptionally low energy houses to the affordable housing sector where fuel poverty is a pressing issue. Houses that are three times better than current regulations in their performance and that will cost below £200 a year to heat has been our driving goal. Over the last six months our first Passivhauses started being constructed on a site near Stratford on Avon. These 14 houses which are being built for a Warwickshire Housing Association will be the first of their type in the county. For our practice it has been a great achievement and the techniques developed are already being applied to other buildings that we design.”
In 2010 the government started a push towards building zero carbon housing by 2016. That deadline never came about due to pressure from the big house builders to scrap the idea, but that did not stop us from looking at new ways to design small houses for the average household. We soon came to the conclusion that we could not continue ‘bolting on’ more solar panels and insulation to existing designs to reach these targets. By reconsidering our approach to design and construction this allowed us to increase the efficiency of the buildings we developed and in so doing contribute towards reducing their carbon footprint.
The passivhaus standard was developed in Germany in the early 1990s by Professors Bo Adamson of Sweden and Wolfgang Feist of Germany. The passivhaus standard can be applied not only to residential dwellings but also to commercial, industrial and public buildings.
“A passivhaus is a building, for which thermal comfort can be achieved solely by post-heating or post-cooling of the fresh air mass, which is required to achieve sufficient indoor air quality conditions – without the need for additional re-circulation of air.”
How does that work in practice?
The building is super insulated and all cold bridges between the interior and exterior are carefully designed out. The building is incredibly air tight with careful attention in the design to prevent gaps in the construction where warm air can leak out of the building. Then fresh air is pumped continuously into the house passing across a heat exchanger ventilating the building, keeping it fresh and pollen free. This approach maintains the building at 20 degrees C all year at little cost.
Finally, care is given to the orientation of the buildings and to external solar shading. We aim to maximise on sunlight during winter days but we want to guard against overheating through those same windows in the Summer. To this end traditional external shades have been sourced to provide that shading. Finally we have taken a wholly British approach to the construction methods, adapting British construction techniques to Passivhaus design rather than using imported European methods.