How to find the right land plot for a passive house?

Every real estate book or expert will tell you the main rule when buying real estate: location, location, location. Personally, I would also recommend to put aside the passive house aspirations for at least a while and focus on what do you want / need in the future as this is way more important.

Try to answer the following questions for yourself:

  • Where do I want to live? (Countryside or City)
  • Is nature important to me, or do I prefer short commuting times?
  • For how many people should the house serve?
  • Is it a pure investment or an asset I am going to personally also use?

The criteria you should consider for a passive house land plot are following:

  • Orientation: South or South West as you will want to harvest the solar energy as much as possible
  • Shade: Try to see if there are shade criteria which you cannot control and will have an impact on your life (for ex neighbours trees, a mountain, etc). Generally try to avoid places where there is shade more than 20% of the time of a daylight
  • Micro climate: some places have microclimates which are quite different than the rest of the location. There are places where within a range of 2km there is a 3-4 degrees temperature difference
  • Potential development: try to see if there is a risk that your neighbour will build a tall building which would obstruct the sun to shine at your house and therefore minimize the solar gains.

Avoiding the most common passive house trap

The biggest trap when buying a passive house is marketing

When I first considered building a passive house I did the easiest thing I could do and most people would actually do: contact some construction companies to get offers. Now I am living in Austria and that gave me the first reality check: the prices per m2 for a passive house are starting somewhere at 2000 eur/m2 with averages at cca 2500 eur/m2.

Quite shocked I went to Blaue Lagune in Vienna (a showroom of about 50 houses) only to find out that the cheapest non-passive house construction in Austria would start somewhere at 1200 – 1300 eur/m2. I was instantly out of budget with all my plans.

And also to find an interesting marketing gimmick: some companies were trying to sell houses by associating them with the word “passive”, but only have one or two elements which correspond to the passive house standard. Usually, that was walls or windows. The problem here is, however, a bit deeper: for example, if you buy/build a house which is super insulated – to meet all the standards and you don’t have any ventilation unit, you will end up having a very bad experience since the air is not going to circulate through walls and you will end up with a huge deficit of fresh air. The quality of living and comfort, in this case, would be lower than in an older, conventional building!

Since I was born in Romania and still have friends and family there I thought the next logical step would be to check the prices of construction companies from Romania which has a lower labor cost = cheaper construction. To my amusement, almost every company I talked to was able to build a passive house. The trouble came in only when I started to ask how do they measure what they deliver and the word “blower door test” was a neologism for them 🙂

Bottom line lessons: 

  • A passive house needs to have all the elements, otherwise, it’s just a box of insulation material, potentially even harming your health due to the lack of fresh air
  • If you pick a company to build the house for you, make sure to include in the contract several blower door tests + thermography if possible and make them liable in case they don’t meet the criteria
  • Ideally, pick a company which can offer you a certified passive house – you don’t get the certificate if the facts are not there and the standards are not met

So here I am in a strange situation: on one hand having some quite reputable companies in Austria but needing to slice down the size of the house to the half in order to meet my budget or to risk with a company from Romania.

Needless to say at the time of writing this I am still not  100% decided but I am exploring a third option: get the material and self-build the house with the help of some construction professionals who I know are good. I will wait and evaluate the offers I get and get back with details.

In the meantime, I will post some articles about how to pick the right land plot to buy for your house and what are the elements of a passive house.