Odor from uninsulated slab on grade

[AreliC]

Need some good advice! We have an L-shaped house, a so-called Wihlborgsvilla, in Skåne. Most of the house is on a slab on grade but without proper insulation. The insulation is basically just a lot of leca balls under the slab. The house was built around 1970 and is a total of about 200 sqm. Previously, there were impregnated embedded sills under the walls, not throughout the floors, those were removed about 25-30 years ago. This looks completely correct (wood lying in plastic under the walls, not damp). We have had the house for about 17 years, and a thicker vapor barrier has been on the floor, and we have sometimes felt a little smell, but not much, and no typical "mold or summer cabin smell." Now to the point, the parquet floor and vapor barrier have now been removed because the radiator pipes in the slab need to be replaced (leak in an unknown location in the system, so replacing everything due to old age anyway), and now that it is being torn up, it smells strongly of earth/mustiness. There are some cracks in the concrete slab; maybe it's the smell from the leca balls? I am now at a loss as to what to do and would gladly receive recommendations. If you ask someone who sells ventilated floors like Nivell, it’s of course the only solution, but is that so? Could you also put a new good vapor barrier? Most of all, I would have wanted to cast a concrete floor over everything, having concrete instead of parquet since all rooms have patio doors and no one takes off their shoes, but since the slab is uninsulated, this could be difficult considering cold floors. Could this have been a solution otherwise? Tips on a good company to solve this floor problem in southwestern Skåne are gratefully received, preferably craftsmen with execution experience, not like Anticimex (got hopelessly ignorant advice from them unfortunately).

 

[Albans doktor]

The best option if you don't want to move or tear down the house and start over with a new foundation:

Chisel out the entire concrete slab, except for the part that the walls stand on, of course. Then apply insulation foam to the ground, followed by a layer of self-leveling compound. This gives you an insulated slab and level floors, which you can either leave as bare concrete or cover with flooring.

It might also be worth checking with a firm that measures moisture and radon. It might be a good idea to start there to understand the conditions in your house.

Otherwise, there's nothing wrong with Platon or leveling floors. For example, if you go with a Platon floor, you can have a fan that removes moisture/radon/odor from the house (if you have a lot of that), all at a relatively low building height.

 

[AreliC]

Had a guy over today and didn't think there was any problem, just thought it smelled like dry concrete...maybe you could add an extra moisture barrier from tecca if you don't want the usual vapor barrier with step cushioning underneath.

 

[Albans doktor]

Had a guy there today and didn't think it was a problem, just thought it smelled like dry concrete... maybe you could add an extra moisture barrier from, for example, tecca if you don't want a regular vapor barrier with step damping underneath.

Well, then the easiest and cheapest solution is to restore it to how it was before. How much build height do you otherwise have from the slab up to the thresholds/door leaves?