Hello!
I'm thinking of leveling the old garage floor (concrete slab) but can't find any suitable mortar in the usual hardware stores. Most leveling compounds require some type of coating, but I want to paint the floor instead. Therefore, I wonder if repair concrete can be used for this purpose, e.g., fine repair concrete (10mm-50mm, just within the thickness I need). The alternative is putty/compound for industrial floors, but I guess I could build a new garage for the money it costs
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I'm thinking of leveling the old garage floor (concrete slab) but can't find any suitable mortar in the usual hardware stores. Most leveling compounds require some type of coating, but I want to paint the floor instead. Therefore, I wonder if repair concrete can be used for this purpose, e.g., fine repair concrete (10mm-50mm, just within the thickness I need). The alternative is putty/compound for industrial floors, but I guess I could build a new garage for the money it costs
.Sure, it works great, I've personally poured on concrete slabs (even outdoors) without any issues. 0-4mm is nice as it flows well, similar to coarse self-leveling compound. Just make sure the slab is thoroughly cleaned of dust, salt, grease, and oil, otherwise it won't adhere. This is especially important if it's old concrete that's had cars on it. Sometimes it's easiest to rent an HTC grinder with the coarsest grinding discs and do the floor with it. It might also be worth priming the floor beforehand so it doesn't draw the water out of the concrete and bind dust. Or if you have the possibility, pre-water the floor generously the day before for the same effect.
Apparently, one should use floor leveling compound for the best adhesion of the repair compound, so I guess that's what I'll do. Industrial filler costs around 20,000 SEK for 25 sqm, and I can't quite determine if that's a lot or reasonable.
Grind and prime instead to avoid using floor levelling compound (which itself also requires a completely clean/ground surface). 25 sqm takes a maximum of a couple of hours to grind, so the rental cost won't be too high.
I would choose repair concrete over filler because it is more durable for studded tires and more salt-resistant. With filler, you usually need to apply a surface treatment like epoxy to get good durability and protection.
I would choose repair concrete over filler because it is more durable for studded tires and more salt-resistant. With filler, you usually need to apply a surface treatment like epoxy to get good durability and protection.
I just found out that they stopped manufacturing the slurry mortar some time ago (yet they still recommend it in their instructions). The floor surface is already very rough but dusty and has only been used for storage (cars have never been parked there, so oil and salt are not present). I'm going to try cleaning it with some kind of chemical for removing cement residues and possibly cast a 1 sqm test. According to their (Weber) instructions, no slurry is needed if the surface is rough and clean - but that’s relative
If cars have never parked on the surface, it is sufficient to pressure wash the surface. If you have the option to rent a hot water washer, that is even better. The chemical for removing cement residue is closest to hydrochloric acid, and in that case, it's better to grind or hot water wash with high pressure.