the first Certified Passivhaus in England, by Seymour-Smith Architects

the AI PassivHaus


For more images of the finished project click here

the vision

The UK industry has a very long way to go in terms of building houses for the future, and we wish to address that. Not only have we created the first certified Passivhaus in England (certificate awarded by the Scottish Passive House Centre in January 2010), we also want to bring the Italian catwalk to eco houses, proving that you don't have to knit your own sandals to be an environmentally conscious builder.

the design

Aesthetically, even though the site is in a very prominent location at the top of a hill in the Cotswolds Area of Outstanding Natural Beauty, the design of the house is very bold. The existing barn (that will be our office) has now been carefully restored, and the new building underneath and adjacent to it, is in contrast, strikingly modern. Being dug into the hill to be invisible from the surrounding countryside, this is essentially a stealth house, with absolute minimal visual as well as environmental impact on landscape.

The house is entirely glazed to the south, and the rest of it being earth-sheltered and therefore highly insulated creates the perfect passive solar design.

The structure of this underground house is entirely concrete, much of which is left exposed internally to exploit the benefits of its thermal mass. It is insulated and waterproofed externally for the same reason.

the process

There are 3 walls of the existing barn that we promised the planners that we would keep intact during the building of the house below. This was instrumental in our being granted planning permission to build in such a prominent location in an Area of Outstanding Natural Beauty.

The (not entirely normal) process we followed to support these walls was:

  1. walls strengthened and tied together, using Helifix’s Heli-beam system
  2. walls then underpinned, using reinforced concrete that was continuous from one bay to the next, to effectively create reinforced concrete beams under each wall
  3. construct a steel frame to support these reinforced concrete beams and the walls over
  4. dig a very large hole, leaving the barn walls suspended above it
  5. construct new house underneath
  6. once new house structurally complete, pour in-situ concrete to zone where steel beams sit between underpinning and house below. Then cut off protruding steelwork, and think of many imaginative uses for it... 

 The rest was a doddle...