Technology in passive house

Hello forum members,

We are planning to build and I am considering the method and which technology it should be. So far, I like the LEGO bricks (Isorast) and with the bricks 42.75 cm. Is it possible to build the house passive? OK. I have to insulate the foundation slab and roof well and use triple-glazed windows. But from the conversations with the advisors, they recommend heat pumps, underfloor heating, so that the house gets the desired temperature. Actually, in a PH you don't have to invest much in technology, otherwise you are building a low-energy house (which is cheaper). Will the extra costs for PH be worth it for me? I look forward to your opinions.

Whether it is worth it in your case, you will probably have to calculate (or have it calculated) yourself. In my case, the calculation was straightforward. A passive house costs about €50,000 extra. In addition, I have interest of about ~€20,000 (25 years at 3%). The interesting question now is how much heating costs can be saved during that time. But I still have to look that up. It would have to be a difference of €233 for the passive house to pay off even with external capital. It can also be a bit less or more. You would also have to calculate what happens if the energy price or the interest rate rises. Then the whole thing looks completely different again.

Hello, They say a PH has 8% more costs. I received the construction site from the municipality and there are some building regulations prescribed (I have to insulate well). But whether I use 10cm insulation or 25cm (PH area), I think the difference is about 10,000 euros. But how do you get to 50,000 euros? That is a lot and whether it is worth it. The company I want to maybe build with says it is not much more expensive for me. In your case, what caused the higher costs and are these costs comparing the PH with a low-energy house or PH with a normal construction method?

Unfortunately, I do not speak your language and was only able to understand half of it. I will still try to respond.

The problem with a Passive House is the term itself. The insulation of a Passive House is still relatively cheap. I don't know if €10,000 is enough for it. However, the insulation alone is probably not sufficient for a theoretical Passive House. If I read the companies' offers correctly, Passive Houses usually include heat pumps, controlled residential ventilation, underfloor heating, and partly solar systems. All of this together results in an additional cost of €50,000 compared to a normal house.

In my case, I came to the conclusion that I cannot simply decide for or against a Passive House. I have to consider each point individually. Which heating system is suitable for which insulation and vice versa. Whether it ultimately deserves the term Passive House doesn't matter to me. For me, it's purely about the expected costs including interest.

Hello,

If I read the companies' offers correctly, passive houses usually include heat pumps, controlled residential ventilation for supply and exhaust, underfloor heating, and partially solar systems. All of this together results in an extra cost of €50,000 compared to a normal house.

That’s not the whole story, and in my opinion, the €50,000 is very "nicely" calculated by the providers you contacted. A "real" passive house is only allowed to use 15% of the energy, which means that besides the installed technology, the wall construction/insulation/roof must also be right; not to forget the special window elements, which alone cost a good €20,000 more than the usual standard windows for a "normal" single-family house!

Kind regards

8 to 10% additional costs (what are additional costs - what is the basis) are realistic for a passive house, for the large passive house (multifamily house) rather less. These "additional costs" are within the usual range of fluctuations in offers from craftsmen and developers. I am myself a certified passive house planner and have built several passive houses.