Through Sustainable House Day we were attracted to the Passive House concept, as well as the advantages of CLT/Cross-Laminated Timber - on our small block, this suited our ambition for a compact home fully featured for efficiency. The design we have supports these ideals, but also maximises a sense of open space and light, complemented by interior glazing and textured triple-glazed entrance doors.
Our friends at KLH Pacific modelled these plans for structural integrity and calculated how the precision cut CLT panels should be configured for efficient transport and installation; panels were craned in and assembled in two days.
This was then fitted with insulation, cladding and triple-glazed windows. Airtightness is an essential component and our final blower door test gave an outstanding result of 0.12 ACH (Air Changes per Hour) which is well below the Passive House requirement of 0.60 ACH.
Solid interior walls meant we were introduced to wireless light switching, which was a benefit since power only needs to go directly to the light fitting – it also enables the use of smart light control.
The exterior wall cladding is Weathertex which has a better than zero carbon footprint and is 100% natural (97% hardwood fibre & 3% wax) and is painted a light colour for maximum reflectivity. The roof is Colorbond steel, also light coloured. The large mass of sustainably sourced timber in CLT, wood fibre insulation and cladding – which sequesters carbon for its considerable lifespan and then may be dismantled, reused or recycled – offers a major offset against the carbon cost of other elements.
Inside, the floors are matt porcelain throughout - they support thermal mass and are steam cleaned, eliminating the use of chemicals. Interior CLT surfaces remain unsealed.
Passive House is an extremely efficient energy and climate control concept - when we close it up in hot or cold weather we are grateful to be able to enjoy clean fresh air in a comfortable and calming environment.
