Damp Floorboards under Laminate and Carpet Underlay!

[Reginalddean]

I have just lifted up the laminate flooring in my hallway, I was surprised to see carpet underlay under it sitting straight on top of the floorboards?

When I lifted the underlay all the floorboards look damp, to the touch they are also damp ish.

Has the carpet underlay (rubbery waffle type) made the floorboards sweat? I recently uncovered all the outside vents that were covered by paving slabs so the floor hasnt had much ventilation over the past few years.

Any advice or knowledge welcome

Regards

 

[mattysupra]

Blown rubber carpet underlay wont cause them to sweat. Bit of a strange one this is. Must be down to your blocked air vents. Im out for a drink with some top tech guys tomorrow so will bring it up.

 

[Reginalddean]

Thanks for that, I thought it was an odd one! Just to add a bit more, I am planning to sand down the bards and varnish, is this wise?

Cheers

 

[big-all]

Thanks for that, I thought it was an odd one! Just to add a bit more, I am planning to sand down the bards and varnish, is this wise?

Cheers

if youve had no air flow and a bit off damp for years i would want to check the joist for decay

also if your floor boards are nice and tight be prepaired for them to become gappy as they dry out

but yes they should be fine for sanding after dry assuming theres no rot

 

[Reginalddean]

Hi,
mattysupra, did you manage to find anymore out from your drinking buddies?

Its been nearly a week now and the boards dont seem to be drying out, mind you it has been cold though!

Cheers

 

[JohnD]

you have opened the underfloor airbricks, brushed out the cobwebs and dust and got a good airflow?

and taken up the rubber covering to let the boards dry off?

If you've done these things and it hasn't improved, lift a few boards and have a look. Is it bare earth or concrete. Are there obstructions to airflow. Is it damp. Are there pipe leaks.

how far apart are the airbricks and do you have them on all sides of the house or are some blocked by extensions, decking, garages, doorsteps etc

 

[mattysupra]

sorry i forgot all about it. I will bring it up tomorrow.

 

[mattysupra]

just made a quick phone call for you, Follow johns advice first and check the things he said.
We have decided that the damp feel to the floor you have is some kind of thin glue or contaminate or something that makes them feel damp, ( maybe wrong) If there is no river found flowing under your house when you lift up your floorboards and there is correct air flow under the floor, then hire a wood moister meter ( protimeter etc ) and take some reading of the boards, joists etc.
I take it your not doing any wet works at the moment, plastering / new concrete etc? This could also cause a build up of moister this time of year.

 

[Reginalddean]

Thanks everyone.

Matty - I have sort of come to the same conclusion as you, there is ventilation and I have had a dehumidifier on the go for days! It must be some sort of adhesive from days gone by! I will go ahead and sand down and let you know how it goes,

Thanks again every one

 

[Pittsarg]

We noticed stains on our (13 year old) diningroom carpet which could not be removed by vanish etc. On lifting a corner of the carpet the floor looked wet and felt slightly damp/oily. First thoughts were rising damp blocked airvents or a leaking central heating pipe under the boards. When we took up the carpet the whole floor looked uniformly damp. We contacted the firm who supplied and fitted the carpet and they advised us that the underlay used had been 'bulked up' with oily/waxy substances which over the years had released the oil causing the carpet stain and damp looking floorboards.