Europe
Airtightness
Layer
Contributes
to
Low
Energy
Rotorua
Home
Ian and Raewyn Simpson subdivided the Rotorua section that they have lived on for over 24 years to build their dream home. They wanted a home that would be comfortable all year round, with low heating and cooling running costs and the latest in home automation.
The couple chose AJ from Performance Build, a local Rotorua builder, based on his experience building low-energy homes.
To create a high-performance envelope, they used Knauf Insulation to achieve R4.1 insulation in the walls and the Knauf Jet Stream MAX blown-in insulation product in the ceiling.
How was this project implemented?
pro clima INTELLO® PLUS Intelligent Air Barrier was installed in order to maximise the performance of the insulation and minimise energy losses. A Blower Door test was performed and the home achieved an airtightness level of 1.3 ACH (air changes per hour). To put that number in context, average new builds in New Zealand achieve between 5 and 10 ACH at 50 Pascals. A Zhender HRV system ensures that fresh air is delivered to the home year-round at the right humidity levels, with efficient heat recovery being possible with the airtight envelope.
Double-glazed UPVC windows and doors from NK Windows were installed, which include tilt-and-turn hardware for maximum functionality. Windows are the biggest weakness in a building’s thermal envelope, and the Simpsons recognised the need to use better-performing joinery to ensure their desired outcome.
A Maxraft fully insulated slab was chosen to complete the envelope.
An Ata Touch home automation system will allow for remote control of lights, blinds, wall panel heaters, and security alarms from a mobile app.
- Builder - AJ – Performance Build
Airtightness Systems
Vapour check and airtight membranes with humidity-variable diffusion resistance provide the best protection against moisture and mould-infested components. In combination with moisture-active wind-sealing membranes on the exterior, they significantly improve the protection of building components and facilitate a healthier, mould-free indoor environment.
What is a Blower Door?
A Blower Door is a tool for measuring the airtightness of buildings. It can be used for quality control to help find leaks, and it can very precisely measure the amount of air leakage. It is so good at this that it is used by building codes around the world to verify standards for air tightness in construction.
