Damp underneath laminate flooring - what could be causing it?

Alexei

We moved into our (early 70's) house six months ago. The ground floor has some cheap and nasty laminate, which over the last few months has bulged and buckled in a couple of places, near doorways. We'd assumed it was caused by laying it badly with insufficient expansion gap, so left it until now.

Having lifted some of the laminate, it seems we have a bigger problem! Underneath the laminate and foam underlay, there is the original wooden parquet flooring - this is dry around the edge, but damp towards the middle of the room. In places it's expanded enough that the wooden blocks themselves have become dislodged, and it's obvious that this is what's causing the laminate to buckle.

Underneath the parquet is a concrete floor which looks and feels dry (but maybe this is just because the wood has wicked the water away from it?). None of the walls or skirting show any signs of damp.

What could be causing the damp? Is it possible that it's just condensation caused by the waterproof underlay trapping air underneath? Or is it likely that the water is actually coming up through the concrete? There are no obvious signs of plumbing or drainage issues around the house, and the damp proof course in the brickwork is well above ground level.

tony6403

Just a thought - is the "waterproof" underlay in tact? I wonder if the moisture could have been caused by spillage or washing from above?

Alexei

tony6403 wrote: »

Just a thought - is the "waterproof" underlay in tact? I wonder if the moisture could have been caused by spillage or washing from above?

That's possible. One of the areas that's particularly bad is in the kitchen where I wouldn't be at all surprised if there'd been a spill.

I've left one patch of the parquet uncovered and it seems to have dried out well (but is so distorted that I have a bad feeling the whole lot will have to come up). Will take up the rest of the laminate at the weekend and see what state it's in.

From what I've read it sounds like removing 60 square metres of parquet (small fingers laid with bitumen, most of which is still well and truly stuck) is going to be a hell of a job!

tlh858

The damp/wet isn't coming up from the floor - bitumen is waterproof.

Therefore most likely a spill of some kind.

Leif

Alexei wrote: »

That's possible. One of the areas that's particularly bad is in the kitchen where I wouldn't be at all surprised if there'd been a spill.

I've left one patch of the parquet uncovered and it seems to have dried out well (but is so distorted that I have a bad feeling the whole lot will have to come up). Will take up the rest of the laminate at the weekend and see what state it's in.

From what I've read it sounds like removing 60 square metres of parquet (small fingers laid with bitumen, most of which is still well and truly stuck) is going to be a hell of a job!

I've lifted 20 square meters of the same stuff. It is not that hard to lift, but you are left with a nasty sticky mess underneath. And the skirting is probably fitted on top.

Do you dry clothes indoors? Does your bathroom get steamy due to no fan?