No damp proof membrane beneath concrete floor

[dogfonos]

Would really appreciate some advice/suggestions...

Our 1958-60 bungalow doesn't have a sheet of damp proof membrane beneath the concrete floors. Instead, the concrete surface is coated with bitumum/tar-like substance onto which wooden parque floor blocks and cork tiles have been laid/stuck. The bitumin layer meets the wall's DPC (more or less!)

In one room, I need to remove the cork tiles so that a new floor can be laid - not sure what flooring yet. Could you please tell me what my options are for damp proofing the floor, e.g. is it considered acceptable for a floor's DPM to consist of a top coating of tar these days?

Thanks in anticipation.

 

[^woody^]

With luck, the coating may remain intact. If not, with even more luck there may be no damp issues

Otherwise there are liquid DPM products to coat the surface.

Can't the tiles remain?

Reposting in the flooring section may be better

 

[tim00]

Woody is correct, and i'd second that if at all possible dont disturb the tile. If you remove the tile you will be facing the bitumen layer with, probably, a now broken surface, and your choices will be a rock and a hard place: a liquid DPM may not "take" to the bitumen (or create a chemical reaction), and attempting to remove a bitumen layer can be a dockyard job.

Perhaps, first fix down any loose tile, confirm that there's no dampness, and determine on your covering choice, and then come back to these forums for further suggestions.

 

[dogfonos]

Thanks for your advice, Woody and Tim00.

Meant to say there are no damp issues I know of.

I think I need to remove the cork tiles because they have become uneven over the decades due to areas of compression. I did a bodge about eight years ago by placing many thin cardboard cut-outs in the dips to even out the bathroom floor before putting down a hardboard layer then topping with sheet vinyl. Worked quite well but I know it's a bodge and wanted to do it 'properly' (whatever that is) this time round.

About three years ago, I removed a large lounge fireplace and replaced with a smaller footprint one. This involved me adding more wooden parque blocks to the floor using bitumen tar so I understand what an extremely messy job it is - removing the tar layer would be a nightmare as you suggest.

I'll decide on a covering then re-post under flooring as advised. Thanks again.