ᐅ Climate foundation / energy-efficient slab-on-ground foundation

Hello Dirk,

DirkB schrieb:

We are currently planning to build without a basement. Does that make sense?

That primarily depends on your budget and secondly on the intended use of the basement. If it is only going to be a utility basement, you’ll be investing a lot of money underground; if there are difficult soil conditions, even more so.

The basements we have built that are not currently used as living space tend to turn into mere storage rooms over months or years, filled with all sorts of things the homeowners can’t bring themselves to throw away. If you plan to have a large vegetable garden — for example, digging in the spring and harvesting leek in the frost — you will need storage space for the various garden crops. Early potatoes, celery, carrots, and similar vegetables need proper storage. 😉

DirkB schrieb:

Does it make sense to include an energy-saving slab (cost/construction time/self-build/later energy costs/other advantages/disadvantages)?

I looked into it and — honestly? — I don’t really see the point of this type of slab. It is generally thinner, and the underfloor heating is embedded directly in the slab; if I’m not mistaken, the subbase also needs to be prepared differently. All in all, an expensive matter — for what?

I’m not a fan of insulation under the slab because no one can be certain how the weight of the house will affect the insulation; obviously — no one has ever dug it up to check. It probably just looks good on paper.

For years, we’ve been pouring minimum 25cm (10 inches) slabs on gravel and a vapor barrier, followed by a standard floor build-up. Also, I don’t understand installing underfloor heating in a basement unless those rooms are intended as living areas; not even considering the required insulation of the heating system manifold.

Best regards, Bauexperte

Thank you, construction expert.

What is the approximate cost of a complete slab foundation plus 200mm (8 inches) insulation, underfloor heating, and screed? I would expect it to be at least no more expensive than building "normally." And it should only take 3 days... They mention approved insulation. Once it is approved here in Germany, shouldn’t it also be accepted?

Hello YPG. Sorry, I thought my question was clear. I’m not allowed to share links, but try googling Futura foundations 😉

Thanks for your effort 🙂))

Regards
DirkB

Hello Dirk,

DirkB schrieb:

What is the approximate cost of a complete ground slab plus 200mm (8 inches) insulation plus underfloor heating plus screed? I would imagine that it wouldn’t be more expensive than building in the “usual” way.

I have no idea what the Futura costs; for the reasons I mentioned, I never looked into it.

Regards, Bauexperte