Passive House, Strathcarron, Scotland
A passive house self-build in Strathcarron, Scotland, this precision-engineered home was manufactured by MBC Timber Frame
A very impressive air test figure of 0.35 ACH/hr.
- Passive House
- Air Tightness Testing
MBC Timber Frame has been manufacturing precision engineered timber frame homes for the self-build market since 2002. They’ve established a reputation as providers of quality energy-efficient passive timber frame homes.
Passive House standards involve incredibly tight air test figures. MBC ask us to provide the air pressure testing for all of their building developments. This included a self-build project in Strathcarron in the Highlands of Scotland.
The 140mm stud timber frame of the passive house system offers minimal space heating requirements. This allows it to achieve high levels of thermal efficiency with the benefits of a low energy sustainable home. When MBC erect the initial structure of a property and completely seal the building envelope, a Melin Engineer arrives on site to test the building.
Airtightness performance of a passive house is measured in air changes per hour at a 50 Pascal pressure difference between the inside and outside of the building. This is referred to as the n50 value, and is determined by calculating the volumetric flow of air (m3/h) required to maintain a pressure difference of 50 Pascals (v50) divided by the internal (heated) air volume (m3) (Vn50).
This is not the same as the air permeability envelope area (A E permeability) approach generally used in the UK, which ignores internal walls and floors and is measured to the air barrier element. This means that voids between the ceilings and floors and internal wall voids are not included in the passive house volume calculation.
In addition to this, the method of testing is also different. Where the general test can be either pressurised or depressurised, passive house requires both tests to be carried out, and an average of both tests taken as the final result. Although not a regulation, it is advised that a test is carried out at the start, middle and end of the build.
“Melin provide an excellent service on all of our projects. Their understanding of the passive house standard and the lengths they go to offer their expertise mean that we wouldn’t hesitate to recommend them.
Joe Lewis, Director, MBC Timber Frame