Tore down a room in the basement and under all the wood someone had laid asphalt as a surface layer. Have tried sanding off the stuff with various discs but it just smears. Does the asphalt need to be removed? If so, how?
Assume it's kallasfalt. When I tried to remove the asphalt from my basement walls (in connection with re-draining), I tried all conceivable methods that one can manage themselves but eventually had to give up and hire a blasting company. They came with a compressor and a larger model blasting equipment, then disappeared into a black cloud, packed up and drove away an hour later, and then the entire house wall was clinically clean from asphalt around the whole house.
Possibly you could try a diamond cutter and remove both asphalt and a few mm of concrete (if it's concrete). I haven't tried this on asphalt, but I did renovate the balcony that way when it was impossible to sand down old stubborn paint/coating. The risk is that the milling disc clogs up.
Pen
Possibly you could try a diamond cutter and remove both asphalt and a few mm of concrete (if it's concrete). I haven't tried this on asphalt, but I did renovate the balcony that way when it was impossible to sand down old stubborn paint/coating. The risk is that the milling disc clogs up.
Pen
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Found the same thing, it was reportedly used as a moisture barrier and we left it. We added a new vapor barrier on top after thorough cleaning. But we didn't have pure asphalt coating, it was thick petroleum tar or bitumen... which is in fact asphalt... but in everyday language, people usually mean asphalt concrete...
Regarding the diamond cutter, I do think it will stick again; I was thinking of laying steel studs in the room—does the asphalt need to be removed?
Maybe it's the same crap here! My first guess was asphalt, could be some other crap. It sticks like hell anyway!
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Keep in mind that those old asphalt/tar coatings can contain high levels of PAHs, which can lead to a lot of unpleasant substances being spread during grinding and similar activities. Not saying it's the case in your specific situation, but keep it in mind. This type of coating tends to have a strong odor when disturbed, comparable to creosote.
It smells a lot here at home right now, if I leave it be is it dangerous then?
No one knows if I can leave the "asfalten" as it is?
I don't dare to advise you on that without looking into it further and without an analysis of what it actually consists of. PAHs can range from volatile to very "inert." However, you should not perform a lot of work on the material without knowing what it is and without protective equipment.
Looks like I'll have to call a company to come here and do some blasting. It smelled before I started sanding and didn't smell any less after I had stirred it up with various tools.
I also find it difficult to advise on whether to remove or keep it. But since the asphalt is where it is, one suspects it's the only moisture barrier against the ground. If you remove the asphalt, I would lay a moisture barrier before the upper floor and then ventilate the gap via the baseboards. I would also prepare to connect a fan from the gap with a duct out if it later proves necessary.
If you remove it, then lay out a square meter of plastic film on the floor and see if condensation forms on it.
If you remove it, then lay out a square meter of plastic film on the floor and see if condensation forms on it.
Yes, that sounds sensible, I will think about whether the asphalt should stay or not.Pen said:
Thanks for the answers.