Architect Helen Seymour Smith set out to build a Passivhaus but, finding there was very little information on the principles in the UK, worked with Sto’s technical team and visited Sto in Germany to get comprehensive information on how the principles can be put into practice.
The resulting project, built into a hillside in stunning Cotswold scenery, achieves a U value for the external walls of <0.15W/M2K and an air tightness value of 0.44m3/(h.m2) at 50 Pa (0.6 being required for Passivhaus standard and 10 being the norm for houses in the UK).
StoTherm Classic uses a thick layer of EPS to achieve the required U value which is adhered to the wall using Sto-Turbofix adhesive foam to actively help air tightness. This is then coated with StoLotusan render. This render combines unparalleled strength with a unique self-cleaning characteristic, helping to lend the home a sharp, contemporary finish.
Having worked with the system, Helen remains convinced that Passivhaus is the way forward: “It’s a straightforward, proven and workable method of reducing the energy use of buildings. The proposals put forward in the Code for Sustainable Homes are so complex, and seem to require so much interpretation and pointless box-ticking, that I really can’t understand why the UK is not following this established set of principles.”
The minimalist contemporary interior of the house also makes extensive use of Sto products. StoSilent Modular 100 suspended acoustic ceiling panels in a variety of shapes soften the acoustics of a concrete interior and help to define the living spaces in an open-plan area.
As Helen did not want to disguise the concrete structure of the house she did not want to use plasterboard, so, instead, used StoLevell In C and StoLevell in Mur interior spray plaster on all internal concrete surfaces which was then topped with StoColor Climasan – a unique odour-eating paint available in a range of vibrant colours.