Plummerswood Active House

More information about the Plummerswood Active House project can be found here.

 

Plummerswood closeup

Project lead
Sandy Halliday, Gaia Group, 12/1 Gayfield St, Edinburgh, EH1 3NR

Building type, sector and stage
Domestic, Private, Stage, Region

Keywords
Passivhaus, Natural Ventilation, Health, Brettstapel, Solar Thermal, MVHR

Time
6 months into a 2-year monitoring programme

Context
Gaia Architects were commissioned to design a dwelling on a site overlooking the River Tweed in the Scottish Borders. Plummerswood Active House is designed on ecological design principles to create a healthy, comfortable, energy efficient home. This relied on implementing basic, but fundamental, environmental strategies.
Positioned on an east-facing slope and looking south over the Tweed Valley, the house was designed through extensive dialogue with the clients, resulting in a simple, L-shaped layout across two storeys, with the intersection forming the double-height entrance
It is the first house to be constructed in the UK to the internationally-recognised Passivhaus Standard using the glue-less mass timber Brettstapel technique.   The superstructure was prefabricated in Austria and shipped to the site. It was constructed to a six week timetable, in the midst of the winter of 2010, on foundations built by local builders.
Special attention was paid to the avoidance of synthetic and heavily processed materials and those with polluting impacts on indoor climate and waste streams. The insulation is made from low-grade wood fibres bonded by tree resin. It is vapour-permeable, which means that it allows any excess moisture in the structure to pass through it without affecting how well it insulates.
The fit out was by a local builder and the fixed furnishings are a design collaboration between Gaia and Real Wood Studios. It was completed in Autumn 2011.  Plummerswood Active House won the Scottish Homes Award for Architectural Excellence in 2012.

Plummerswood

Targets
Gaia Architects were commissioned to design a dwelling on a site overlooking the River Tweed in the Scottish Borders. Plummerswood Active House is designed on ecological design principles to create a healthy, comfortable, energy efficient home. This relied on implementing basic, but fundamental, environmental strategies.
Passive techniques such as orientation for daylight and solar gain with external blinds, super insulation, thermal mass, moisture mass and air-tightness (0.6 m3/hr/m2 @ 50Pa (0.46 ac/h-1) have been utilised. A wood burning stove comprises the supplementary heating.
Areas of the house that will be subjected to high levels of indoors moisture, e.g. bathrooms, kitchen and wet room, have clay board and clay plaster applied to the ceilings. The intention is that the hygroscopic properties of these materials will help to maintain comfortable humidity levels in the house.

Plummerswood thermal image

Performance
The results of the early DomEARM indicate that Plummerswood uses less energy than a dwelling designed to achieve a Level 6 in the Code for Sustainable Home development ratings but, as it doesn't produce electricity to offset this, the overall CO2 production is around Level 5. The lack of performance of the solar thermal panels due to poor installation, which is yet to be resolved, has been a source of frustration.

Conclusion
The current extensive monitoring will appraise whether the building form was optimised in terms of orientation, assess the contribution of thermal and moisture mass, and examine the relationship in energy terms between client controlled natural ventilation and MVHR. It will also examine the hygroscopic properties of the wet room linings. The occupants are keeping a diary to assist in the analysis.