Concrete floor and walls not 'meeting' can you help solve my problem?

[ChippingIn]

Ok - well, I guess I should start by saying that I'm not sure if it's a problem or 'normal' but I need to know!

Place built in the 60's (we think) standard brick building. Renovating the flat (upstairs). The concrete floor doesn't quite meet the walls (only a scraper can fit down, not talking cm's!). Is this normal?

Really stupid question alert - but... is there any chance that there could be a gap that goes right through to downstairs?

I want it filled - do you think filling it with gypsum (pollyfilla) would be enough to seal up any gaps? I have 20 litres of the stuff to use up so it would be my first preference!! If not, what do I need to use??

I want to seal it up because I want to stop any smells coming in from downstairs. I'm sure the problems are in other areas where pipes are coming through and not here, but while everything is in a mess I want to be 100% sure in every room!

Thank you if you made it this far!

I would have thought (I'm no expert mind) that gypsum is friable, it cracks so something like sealant might be better as it will flex & move with changes in temperature

Yes - I thought that too :( I was just hoping a bunch of people would say 'No, it'll be fine' ...

Any idea if the gap is normal and if there's any chance it could go all the way through to downstairs? I'd tempted to pooft coloured down the gaps and see if they complain ...ooops

I have no idea how concrete floors are 'poured' or what goes under them/in them. Suppose I need to call a builder, I was just hoping the collective MN brain could supply an answer without too much hassle!!

Sorry not to be more positive for you

(But I don't know how they are poured either)

But Katy - you did so well with the willow house ...

Willow house?

Well - I think you called it a tee pee or something, but you know...

Oh yes - significant lack of concrete tho'

It depends on the detailing of the junctions but it is actually probably quote normal - the concrete 'floor' is probably just a screed that sits upon the structural layer of the floor. V.V common.
Polyfilla is a bad idea it will crack and degenerate very quickly and cost you a small fortune. Your floor moves and awful lot more than you think .
If you are putting down carpet, a good underlay & skirting combination along with the carpet should mean you don't have any problems.
If you are putting down hard floors you should think about an insulating layer of somekind as sound transmission will be a far bigger problem than smells.

If you are really concerned I would think about putting down a latex levelling screed which would go across the whole floor and would also smooth out any lumps and bumps in the floor - necessary if you're putting down vinyl, rubber or even some laminates. However I wouldn't really bother unless these other problems exist.

If you've got smells coming through I would ensure that all larger penetrations pipes etc are sealed properly - I would also do this in terms of fire spread protection. And that you haven't got any misdirected vents - its amazing how many flats get built with vents pointing straight into their neighbours

Hi again Wonky :)

I would like to put down a proper wood floor, but for now it will probably be carpet. I have removed the skirting boards and was hoping to make the wall 'good' and paint right to the bottom and not put skirting back on (because I prefer that look), but unsure now, mainly due to this 'gap' though, rather than the wall where the skirting was.

The flat is over a commercial premises and the noise isn't really a problem - but the smell is. I think it's coming up around the gas pipe in the kitchen and the 'waste pipe' in the bathroom. I'm just a bit paranoid about 'sealing' every room as I do it as it's driving me insane.

The tiles are under the current carpet. I suppose there isn't any real reason to lift them, except I just don't like the idea of old junk being under there. I'd rather clear the floor back to the concrete - but I suppose the tiles are adding some insulation and helping with noise reduction. The other thing is they don't go to the edge by quite a lot - about 4 inches.

I would love to screed the floor but it's all ££ and I'm guessing that wouldn't be cheap?

Thanks for your help :)