/ Passive House Design and Certification

What is Passive Design and how do we use it in our buildings?

Our home is one of our greatest investments and the place where we spend the most of our time. We are passionate about understanding the true costs of running our home’s through an indepth evaluation of its performance from the outset. By clearly understanding the performance balanced with our design ethos allows us to create homes which are suitable for our unique landscape and way of living.

A ‘Passive Home’ is a well insulated and orientated building which brings into consideration the occupants and unique site location to regulate the internal environment without the use of additional heating sources. With the use of important NIWA climate data and PHPP energy-modelling software we are able to balance the ‘gains’ with the ‘losses’ to ensure that the internal environment of your home is always comfortable with little to no heating requirement. This method of building reduces on-going livings costs, and improves the living experience that comes with being in a high-performance home, or Passivhaus.

The ‘gains’ are the sum of the heating gains for a project, such as; sun-light entering the home, occupants and heating sources. The ‘losses’ are a sum of the heating lost through the walls, roof, floor, ventilation, etc. The designers skill and experience comes to the forefront in maximising the gains, and the technical understanding of constructing homes for performance is where the losses are managed.

At TAWA Architecture, high-performance practises are designed into all of our building designs, whether it be in the form of a certified PassivHaus, solar-passive home or commercial project. This is where we focus intensely on the building envelope. Our extensive experience in designing high-performance homes in New Zealand over the past 10 years and our specialised Passivhaus software enable us to provide tangible performance-driven results.

Passive House

We are certified Passive House designers and have trained extensively through the Passivhaus Institute (PHI) which is an independent research institute. The PHI has been instrumental in the development of the Passive House concept - the only internationally recognised, performance-based energy standard in construction.

High-performance homes, such as Passivhaus projects, have specific requirements to meet in order to be called a PassivHaus (or Passive House as sometimes called in NZ). These requirements are non-negotiable, and require meticulous planning from the start of the project to make sure all elements work together to the end result.

Many Passivhaus projects have not gained certification due to unknown errors made at day one. If Passivhaus is something you are passionate about make sure you engage an experienced and certified Passivhaus designer.

high-performing homes

How do we prove that the performance energy modelling we do can be accurate?

One of the ways is to carry out a blower door test. This is an internationally recognised testing system that provides tangible results for the project team to use during the build.

The blower door is fitted to a doorway or window opening in the building. It then pulls air into the building and monitors the amount of air that leaks or is lost out of the building envelope. It then provides a test result that is universal throughout the world and allows the owners to benchmark their project. There isn’t a better way to see where parts of the building may not have been built as well as others then using smoke inside the project and seeing it pour out of the home. It is a clear and simple tool for any high-performance building team.

We are trained and experienced blower door operators. We perform blower door tests on all of our Passive House builds and can also test other homes in the Waikato and Bay of Plenty.

PIONEER PROJECT

Our first Passivhaus project was built in New Zealand in 2011/12. This project was a pioneer for the Waikato region, and the clients were, and still are, passionate ambassadors for this type of housing. The project was well-planned, managed and built but we needed verification, and the best way to do this was to install temperate sensors throughout the home and monitor the performance over several seasons and years.

We were very lucky that the owners of the home were skilled in this area and a system was installed to monitor the temperate throughout several rooms within the home, under the ground and outside the home. This provided us with an extensive amount of data to use and a clearer understanding of how Passivhaus worked within the New Zealand climate, which is different to where it originated in central Europe.