Laying flooring on asphalt

newparent77

We are currently having an extension built on the back of our house, with the kitchen wall having been knocked down so the kitchen opens up into the extension.

The floor in the extension at the moment is the concrete slab and is about 1 cm or so lower than the kitchen floor, now the wall has been knocked through. The builders have decided to use asphalt, rather than a concrete screed, to level the floor. They say this will give a smoother finish and match the floor already in the kitchen.

My question is, does an asphalt surface make it more restrictive in terms of what flooring can be laid on it? We'll probably go for some kind of vinyl or perhaps laminate, but didn't know if an asphalt floor would rule any of those out, or mean lots of prep needed doing first?

stuart45

I guess your builders screwed up the floor levels, and are looking for a way out. 10mm is quite thin and pushing it a bit for even the ultra thin screeds and asphalt. However, asphalt was sometimes used in the 50's and earlier, so it can be used.

flashg67

can the gap be made up another way? Some laminate underlays will be 1cm or more, especially adding on the thickness of the laminate, or even more if you go for engineered wood

FreeBear

stuart45 said:

I guess your builders screwed up the floor levels, and are looking for a way out. 10mm is quite thin and pushing it a bit for even the ultra thin screeds and asphalt. However, asphalt was sometimes used in the 50's and earlier, so it can be used.

Self leveling compound will quite comfortably fill that gap. Depending on the size of the area, might need a few bags.

stuart45

Self leveling will go up to around 40mm, so would work. A bag will only do a couple of metres at that depth, so if it's a big extension you will need quite a few bags.

Eldi_Dos

It used to be common for parquet flooring to be laid on a bitumen base, if OP is thinking of that for new extension the builders proposal could be to their advantage.