Bought a 1970s house last fall with a slab on grade without insulation under the concrete. There is insulation under the floor and beneath it an asfaboard. This asfaboard stinks terribly. The smell gets into clothes, etc. I have now bought an air purifier and the smell has significantly decreased but is far from completely gone. I will seal behind the baseboards to minimize leakage into the living space. In the living room, I have a large wooden floor with gaps between the boards that allow the smell to seep through. I will try to find something to seal these gaps with, or alternatively, lay a new tighter floor on top.
I suppose I will eventually have to tear up all the floors and get rid of the smelly asfaboard, but right now I probably don't have the funds for such a renovation. I don't really know how much it might cost either. The house is 75 m2 on one level.
Anyone with experience of smelly asfaboard and solutions for this?
Best regards.
I suppose I will eventually have to tear up all the floors and get rid of the smelly asfaboard, but right now I probably don't have the funds for such a renovation. I don't really know how much it might cost either. The house is 75 m2 on one level.
Anyone with experience of smelly asfaboard and solutions for this?
Best regards.
Yes, the floor is raised. I had Anticimex at home a week ago who conducted ventilation tests for the installation of subfloor ventilation. We cut a hole in the floor and connected an exhaust fan and another hole further away to see if the air was being drawn downward. Unfortunately, we couldn't get the airflow to work at all. Probably the floor is constructed with closed modules type. Big disappointment.
Could one install a fan on the outside of the house and make a hole through the wall at a height just above floor level to extract the smell at floor level that seeps up from the wooden floor, do you think? Bad idea?
Hi Erik!
It's hard to say if the asfaboard is damp. It didn't feel damp. I took a piece and put it in a plastic bag to see if any condensation would form, but it remained dry in the bag. However, it's not unreasonable to think that it smells due to moisture since it is in direct contact with the concrete slab that lacks underlying insulation. I think the asfaboard that is at a distance from the concrete slab smells less.
No, I don't think it smells like mold. The smell is chemical from what it's made of.
I don't see any other proper way out than eventually tearing up all the floors and throwing it away. But that's a big project since the entire floor needs to be re-insulated, etc. It's not something I'm able to do right now. Temporarily, I'll seal gaps between the walls and the floor with caulk and continue using the air purifier, which removes a lot of the smell in the house.
It's hard to say if the asfaboard is damp. It didn't feel damp. I took a piece and put it in a plastic bag to see if any condensation would form, but it remained dry in the bag. However, it's not unreasonable to think that it smells due to moisture since it is in direct contact with the concrete slab that lacks underlying insulation. I think the asfaboard that is at a distance from the concrete slab smells less.
No, I don't think it smells like mold. The smell is chemical from what it's made of.
I don't see any other proper way out than eventually tearing up all the floors and throwing it away. But that's a big project since the entire floor needs to be re-insulated, etc. It's not something I'm able to do right now. Temporarily, I'll seal gaps between the walls and the floor with caulk and continue using the air purifier, which removes a lot of the smell in the house.
Ok!Dark Väjder said:
It can be hard to distinguish mold smell sometimes, I know that myself. But I probably still think it's mold, because moisture itself doesn't smell, it's the activity from mold spores that gives the smell. Organic material (wood, asfaboard, etc.) that is in direct contact with concrete always absorbs moisture, more or less. And moisture, organic material, along with reasonable temperature is a perfect breeding ground for mold spores. A clear sign that there is mold in a house is that clothes and items smell long after leaving the house!
But as you've already said. Eventually, the only way is to tear up the floors. The risk is just that it can get expensive! Good ventilation helps in the meantime. But one should keep in mind that breathing air with mold can cause allergies and asthma, just so you keep that in mind.
I found a couple of articles that might be interesting. Here is some information about how houses were built in the 70s, slab on ground, etc. =)
http://www.fuktsakerhet.se/sv/delar/grund/platta/Sidor/default.aspx
http://www.byggskadeteknik.com/fukt_info.php
P.S. If the Asfaboard has become moldy, this remains even if the moisture itself dries out. Mold is a fungal organism (whose spores are in the air around us all the time, but it's only under favorable conditions with moisture, organic material, temperature, etc., that the mold begins to grow and cause what we don't like
)Regards
Thank you for your post Erik. I have received a quote from Granab for the floor joist system with floor ventilation. I should manage with a budget of 100,000 SEK including new laminate flooring throughout the house if nothing unforeseen arises, provided I do all the work myself. Approximately 75 m2. The question is whether I will increase the value of the house if I do this?