What is this black shiny rocky stuff kitchen floor?

[diycider]

I am taking up our kitchen floor. It has big flags down layed on cement. I found out part of the floor underneath is concrete, part is boarded, then there is an area struggling to take the cement up. It's not coming up well and I'm not hitting a floor. I've hit this black stuff? It looks like shiny charcoal and smells like it but I know it isnt. Does anybody know what it is and if there should be a floor underneath it?




Cheers

 

[Keithmac]

Damp proofing?.

 

[Newboy]

is it soft or brittle?

 

[Tigercubrider]

Looks like bitumen - the dpc.

 

[bobasd]

could be, as above, bitumen or a thin layer of asphalt. it could have served as a DPM aka a Membrane.

 

[Deleted member 174758]

I'm with Bob on this one. I reckon it's asphalt which is laid hot and sets like rock (which after all is what it is). I've seen it laid over old uneven flooring many times at 3/4 to 2 in thickness. As said it is waterproof and highly durable. It can take a heavy (5 to 10 kg) breaker or even a road breaker to smash it out in a reasonable amount of time. You may be able to do it with a rotation stop SDS drill if its thin enough, but it'll probably take quite some time. Not really a job to do with a club hammer and bolster chisel, though

 

[cdbe]

It's in a lot of old terraced houses round our way - usually on top of thick stone flags - levels and forms DPM. Unless it's too high try and leave it in. To get it up, if you can get something under (flat chisel) to lift it up a bit it's very brittle and breaks easily with a big hammer - the ones I've done it hasn't actually stuck to what's underneath.

 

[diycider]

Thanks all, I didn't get an email notification that people had responded! I had a friend look who is in the trade and said why am I that low haha. He says it is membrane/damp proof.