Engineered boards over quarry tiles - good or bad idea?

[M1ll1e]

Hiya,

As the title suggests I've got a room with old quarry tiles on ash. They are nice and level and very stable so I that respect perfect for laying a floating floor over them.

The issue I have is damp. The tiles used to be covered by a cheap foam backed carpet (before I bought the house!) and this didn't allow the quarry tiles to breath. Consequently the damp meter was off the scale. Now I've ripped up the carpet the tiles are fine and dry.

So my question; if I lay engineered boards and an underlay over the quarry tiles, will the damp return?

Cheers,
Millie

 

[mikeey84]

Unfortunatly I think the answer is yes, although I will be happy to be disagreed with.

I had a similar situation, and I used a cement based tanking compound on the tiles first (about 4mm deep) to waterproof them first.

 

[crazydaze]

You could lay F-Ball Isolator first, then the underlay and Engineered boards, or a high moisture resiliant 2 part liquid DPM, Screed then polysheet, underlay and Engineered flooring.

 

[M1ll1e]

Thanks Crazydaze. I wasn't sure if sealing it was a good idea. I thought quarry tiles eventually disintegrate if sealed over?

 

[crazydaze]

F-Ball Isolator allows the floor underneath to breath by creating an air pocket, log into their website for more info.