Passive House Vision … Then Costs

22 May 2019 by Jason Quinn

This month I’ve been travelling and speaking to a lot of passionate building designers and architects. They want to design better houses & buildings than the legal minimum. They want buildings to be more; more beautiful, more healthy, more comfortable, more durable. They want them to be a legacy we can be proud to pass on to future generations. They can visualize these buildings, but they’re frustrated by clients that focus on cost first and worse, only first cost.

I can understand their frustration & want to help overcome this thinking. Luckily it so happens that Jess Berentson-Shaw from provided a great evidence-based framework on how to do that at the South Pacific Passive House Conference in Wellington this year. Her process has four steps to a well framed argument based on positive vision. During her presentation she went through how when you encourage change by discussing the negative reasons with the current situation, people don’t remember the positive things you talked about, only the negatives. If you really want to convince those people that can be convinced, then the first step was to lead with a positive vision based upon shared values with the person you’re talking to. Then describe the barrier to that vision, the solution to that barrier, and then finally come back to your vision and what it means for the people in their lives. Talk ‘People and Planet not Dollars and Cents’.

To me the vision of Passive House is of healthy, comfortable buildings and homes that leave a legacy to the world. It is so easy to talk about all that is wrong with the way we build now and the poor health, miserably cold and short sightedness of it all. But we will not convince those that can be convinced with only that pitch. We need to focus on the positive things about Passive House and very high-performance buildings: health, comfort and legacy.



Passive House buildings are healthier, and we need to speak more about this and less about technology. We should talk about the six days you’re not sick each year because you live in a Passive House or very high-performance building. (This has been shown through research in Europe see Diana Ürge-Vorsatz’s presentation at the 8th International Conference on Energy and Environment of Residential Buildings Wellington, November 21, 2018.) We can have new buildings that heal us and help us to do our best in the world. Fresh dry air all the time, not just when the weather is nice, keeping hay fever allergies away. Healthy Homes without excess winter mortality, with decreasing asthma rates, and no children going to hospital with housing related disease. Homes where the towels dry themselves in the bathrooms as the house keeps itself dry. You don’t need to manage the building to keep it dry as it was designed and built to be healthy for you.



Warm healthy homes in winter and you don’t think about the heating cost any more than you do about the refrigerator running cost because it’s the same low cost. You just don’t need to think about it anymore. I was talking to an architect this past weekend and she was telling me about a cool night recently when she woke up it was just so much easier to get up and get dressed; and then she realized ‘Oh I left the heaters on’. The home was warm and comfortable, and it made such a difference in how she felt. Homes and buildings can be that way all the time, we just need to design for it. Your home can be like that quiet perfect spring day where the air just feels right. Comfort is not only temperature and fresh spring air, but quiet too. You can close out the noise of the world when you like or let it in



Healthy, comfortable buildings can also enrich our lives and our society. Buildings should outlast the builder and provide long term value to society. We can build buildings and homes that benefit the world long term; just like organic farms that have better soil the longer they are farmed. Just like that old advice on planting a tree. ‘The best time to plant a tree was 30 years ago and the next best time is today. We could have and should have built Passive Houses ten years ago but the next best time to build Passive House is today. Addressing climate change is vital and reducing CO2 emissions by reducing heating and cooling energy usage by 90% through Passive House is one of the only profitable paths on the way to a zero-carbon society.


What’s the biggest barrier?

Many folks blame the clients and their focus on first cost, but I think the biggest barrier is the architect & designers belief that first cost is the barrier for every client. If clients were truly only concerned about first cost, then they would go directly to group home builders or prefab flat-pack home vendors (Bunnings?). Instead they have come to speak to an architect or designer in search of something better. Our clients (and us as well) make decisions with our emotions first and then use logic to justify that decision.

If we can help our clients feel the vision of healthy, comfortable, legacy buildings & homes then it becomes a matter of justifying that first cost after they’ve chosen to pursue that vision. This is great. Our clients know that they can get better homes by working with us. We need to share a better vision of healthy comfortable homes that leave a positive legacy for society, addressing climate change.

For the clients that have that vision the next step is to set their logical mind at ease by justifying their decision with cost. You need to design to a realistic budget while keeping the vision in mind. At some point someone will want to know how much they could cut-back the initial costs by giving up on health, comfort, legacy and climate change action. Almost everyone is going to be borrowing money to build a new home and one of the most important numbers is their future monthly bills. Even if people pay more for a Passive House upfront incurring higher repayments, the reduced ongoing energy bills are significantly less. You can easily end up with the same monthly bills in total but have all the added benefits of a Passive House. (See sidebar for calculations.) If we as the architects and designers can first help our clients feel the vision of a healthy, comfortable, legacy home and secondly logically show the costs are the same we have the best chance in convincing those that could have been convinced.



As an example, if you could save heaps of heating costs with some additional investment then it would make sense to invest money up front until your increase in mortgage payments matched the decrease in energy costs. This chart assumes that interest rates are 4.5%, building costs are $4000 per square meter and electricity costs 33¢ per kWh and plots the matching increase in mortgage that makes sense against the energy savings for electric resistance and heat pump heating. It is different for every house but typically for an Auckland home the savings on heating alone are 75 kWhr/m2/year for a home heated to 20˚C all winter and 170 kWhr/m2/year for a home in Christchurch. For this typical home you could invest 5-14% more upfront in Auckland and 10-30% more in Christchurch and have the same monthly costs.