Hi,
I have a guest cottage measuring 4x6 meters that I plan to extend to 4x12 meters. I will extend 3 meters forward and 3 meters backward.
The guest cottage currently stands on an uninsulated concrete slab.
I thus need to cast 2 new slabs of 3x4 meters each.
Is there any point in making these two slabs insulated? Like edge elements-foam plastic etc..
Or should I just build a form of timber and reinforce it?
The idea is that the floor in the existing guest cottage should be vented in some way. And perhaps the same in the newly built parts?
/K
I have a guest cottage measuring 4x6 meters that I plan to extend to 4x12 meters. I will extend 3 meters forward and 3 meters backward.
The guest cottage currently stands on an uninsulated concrete slab.
I thus need to cast 2 new slabs of 3x4 meters each.
Is there any point in making these two slabs insulated? Like edge elements-foam plastic etc..
Or should I just build a form of timber and reinforce it?
The idea is that the floor in the existing guest cottage should be vented in some way. And perhaps the same in the newly built parts?
/K
With a ventilated floor, you can handle ground moisture without any problems, but on the other hand, you get much better energy efficiency if you choose to insulate the slabs.
Are you considering having waterborne floor heating? In that case, you might be able to cast the existing slabs 15 cm higher than the slab in the existing guest cottage, then lay plastic + 10 cm of cell plastic + 5 cm of concrete with floor heating in the old section. Then you get waterborne floor heating throughout the entire cottage, and you should be able to do the entire casting in one go. However, you lose a bit of floor height inside but not much more than if you build with ventilated floors, and I believe that this solution might be both better and cheaper than, for example, a nivågolv. Nivågolv costs around 1000 SEK/sqm, while cell plastic and concrete are considerably cheaper.
Are you considering having waterborne floor heating? In that case, you might be able to cast the existing slabs 15 cm higher than the slab in the existing guest cottage, then lay plastic + 10 cm of cell plastic + 5 cm of concrete with floor heating in the old section. Then you get waterborne floor heating throughout the entire cottage, and you should be able to do the entire casting in one go. However, you lose a bit of floor height inside but not much more than if you build with ventilated floors, and I believe that this solution might be both better and cheaper than, for example, a nivågolv. Nivågolv costs around 1000 SEK/sqm, while cell plastic and concrete are considerably cheaper.
Mmm. Ok. Have been considering those lines as well. But I'm a bit worried about moisture migration upwards from the existing slab. What will happen in the layer between the existing slab and vapor barrier (plastic)? Won't there be evaporation there?
It might get a little damp there, so it could be wise to treat the slab with anti-mold agent before applying the plastic. But overall, it shouldn't be a problem if you have a little moisture under the plastic. It won't get through the vapor barrier. Just to be safe, you can lay double layers of construction plastic under the foam plastic.
And underfloor heating would have been nice in half of the cabin at least. Where it is supposed to be a guest cabin. The other half will be a workshop.
I've read a bit about reverse moisture migration. And it seems that most are of the opinion that it is not suitable to insulate and pour on top of an existing uninsulated slab together with underfloor heating.
So I'm a bit confused...
I've read a bit about reverse moisture migration. And it seems that most are of the opinion that it is not suitable to insulate and pour on top of an existing uninsulated slab together with underfloor heating.
So I'm a bit confused...