Concrete floor with hole in rubbery stuff

[Metame]

Hiya
New here. I am buying a house that needs a bit of tlc. It has a quite big kitchen extension with ck Crete floor covered in layers of rubbery stuff. There is a hole in the middle of the rubbery stuff. See pic.
This hole is in front of the sink which has clearly leaked some due to state of the unit. Could this have damaged the rubber - or something else?
I want to put down oak laminate in here and wonder how I patch this up best so I can do so.

Many thanks

 

[Deleted member 174758]

The black "rubbery stuff" could well be a layer of bitumen which was used as a form of DPM in houses from around (AFAIK) WWI period or a little earlier up until the 1970s in some areas. The problem with it as a damp proofer is that it eventually cures, starts to crack and breaks down, so you can't rely on it to be effective. The white stuff could be anything - the photo isn't particularly clear. Were I you I'd think in terms of getting an effective DPM in there, beneath your new finished floor. This might be as little as a skim of self levelling compound with a coating of liquid damp proofer on top, but I wouldn't depend on that bitumen alone to keep the underside of your flooring dry

 

[Metame]

Ah thank you! It does feel very plasticky / rubbery and slightly bouncy. Not what I think of with bitumen but I don’t know much about much lol.
You would tear it up, Do a selfnleveler and damp proof membrane or coating then? Only half the room had this rubbery layer so that is probably a good shout to do the whole thing again as if need to bring the rest up to level emayway as it’s quite thick.
There is no sign or smell of damp or mould anywhere I’m relived to say.
The pic I noticed only looks clear when you click on it. Not sure why it’s like that.

 

[Deleted member 174758]

No, I think I'd leave it in. It might not actually be bitumen (you didn't say how old the house was, did you?) - it could possibly be rubberoid tile adhesive, but that is generally very thin, whereas a bitumen layer tends to be thicker (a few millimetres) and can exhibit straight fracture lines where it has been broken through, similar to the straight lines around the area if damage in your photo. Bitumen can remain elastic for decades and can soften in warm weather, such as we are having at the moment. If you leave it in you will still benefit from having at least a partial moisture barrier in place, even if there are breaks in places. It might be with it only covering part of the room that the room was originally two rooms, one with a parquet floor (the parquet blocks were traditionally beded into hot bitumen) and that this is the remnants of that. From one small photo it is very difficult to say, so it's really a guess based on experience (in mycase as a joiner who has repaired and relaid a number of traditional parquet floors - not as a professional floorer, although I do often work with them)

 

[Metame]

Ah thank you for explaining. Sorry I probably left out lots of useful info. The house is pre 1900s stone end terrace.
The extension is more recent but no idea how recent. Looks like it was indeed perhaps split into kitchen and dining room so this flooring is only in the kitchen part. Would some kind of leveller or floor patch work to fill in the hole then do you think? The rest looks like it is still doing it’s job. I only have the photos from the viewing and it was quite dirty with rat droppings so didn’t look too closely or take many pics sorry.
Would you lay something similar over the bare concrete section to level that up with the kitchen area then?

Thanks so much for letting me pic your brain. Been looking at used parquet and tongue and groove wood flooring. I can lay laminate fine but never tried my hand at those. Would love to have them but wondering if they would be really tricky, especially if they are mattered from pre use - which is the only kind I could afford!
Thanks very much

 

[crazydaze]

From the photo, if you plan to fit wood flooring, the correct preparation would be to grind the black material off the floor everywhere. Then you would apply a new Liquid DPM like F-Ball F77 or similar over all floor areas. Then you would apply a primer and self levelling screed over all areas, possibly two coats, and fit the wood flooring over that.

 

[RandomGrinch]

From what I can see, (zooming in a lot on the photo), it looks to me as if you may have square vinyl floor tiles?



Is it possible to confirm this?
Not to put you off or worry you (as it really isn't a big problem), but some vinyl floor tiles and adhesive contained asbestos.
If this really was the case, it might be better to cover over as J&K suggests, rather than grinding it off

Edit:
Although looking again, I'm in two minds - the tiles definitely look square, but some bits look rubbery, whereas other bit look a lot like vinyl.
I haven't come across old rubber tiles before, but neither have I seen vinyl degrade in that way.

 

[Metame]

Thanks for the advice on how to sort the floor properly for wood. It’s likely I will stick with laminate in reality. I don’t k ow if that changes anything. Now you mention it I remember seeing faint joins like the top layer was formed of tiles of some sort. Could well be vinyl. There isn’t a lot of difference between that and rubber texture in my uneducated mind!
I didn’t know about the possibility of asbestos.
I will probably patch that and somehow try to match/level the other half of the room, perhaps in the steps you suggested of a liquid dp and screed to bring it up level. Got to stop the rats getting in first job lol

 

[Metame]

I have found another better pic which shows clearly it is made of some kind of tiles. You can see how it only comes half way across the floor too.

There are a couple of significant dips in the exposed concrete area. I take it I would fill and then damp proof? Thanks

 

[crazydaze]

I have found another better pic which shows clearly it is made of some kind of tiles. You can see how it only comes half way across the floor too.

There are a couple of significant dips in the exposed concrete area. I take it I would fill and then damp proof? Thanks

You would lift the tiles, clean the floor area, lay a Liquid DPM over the whole floor area, prime and then screed to level (assuming thats back to bare concrete under the tiles).

 

[Metame]

Ok yes best to just do the whole thing from scratch. Thanks
Any tips for lifting this kind of flooring? Thanks

 

[RandomGrinch]

Ok yes best to just do the whole thing from scratch. Thanks
Any tips for lifting this kind of flooring? Thanks

As above, it looks as if the flooring will come up without a problem.
But I would send a sample of a tile (and another of any adhesive) to be tested for asbestos - test kits can be bought online for around £25.
If the tiles do contain asbestos, it has implications for how you remove them and how they are disposed of legally.

 

[Metame]

Thanks very much for that!