Best underlay for laminate flooring on wooden f/boards?

[bobgroups123]

Hi,
have a room on ground floor. I have a builder helping me out and laying laminate flooring. Don't know the brand he is getting but he said it's approx 10mm board. Floor is mostly wooden floorboards. I have a small section of concrete at one end of the room where a chimney used to be.

Elsewhere on the internet I've seen "On a ground floor we recommend overlaying with a non-polythene vapour barrier". Where do I get this? Are they all the same?

Is there an underlay that has reflective foil on one side for heat retention and to prevent the room getting too warm in the summer? - just recalling an idea from a neighbour....

Thanks, Bob

 

[crazydaze]

you dont want moisture barriers or foil underlays anywhere near the wood areas, underlay wise, use fibreboards or something like timbermate (without the foil back) Avoid the thin foam underlays.

 

[bobgroups123]

Waht about the small concrete area where there was a chimney board before? there are also a small row of cermaic tiles in front of the concrete. These were there when there was a chimney? does not appear to be damp and in fact fibre board was there before. Just really checking is it ok to have fibre board over the concrete patch and the small row of tiles in front? Rest is wooden floor boards and I'll just go for the green fibre boards over that. then lay new laminate.
Thanks

 

[crazydaze]

Waht about the small concrete area where there was a chimney board before? there are also a small row of cermaic tiles in front of the concrete. These were there when there was a chimney? does not appear to be damp and in fact fibre board was there before. Just really checking is it ok to have fibre board over the concrete patch and the small row of tiles in front? Rest is wooden floor boards and I'll just go for the green fibre boards over that. then lay new laminate.
Thanks

You will almost certainly be ok going straight over with fibreboard, technically you should probably pop some poly sheet over this small area before you lay the boards

 

[Floorsave]

Hi Bob,

When laying any wood flooring or laminate over a concrete base then a damp proof membrane should be laid to stop any moisture from the concrete getting into the flooring.

You can buy underlays with this already built in. There are foam underlays with ether a plastic sheet or a thin layer of foil attached.

To get some heat retention then a rubber underlay would be best with a silver or gold foil already attached.This will give you some thermal qualities.

 

[WoodYouLike]

You better reread what the OP has written Lou - most of the area he has have floorboards as underfloor, only a tiny bit is concrete.

Your advice puts him on the wrong foot!

 

[Floorsave]

There is no reason not to use an underlay with a built in damp proof membrane on a timber floor as long as there is no underfloor heating.

If you are using fibreboard, then you should use a DPM sheet of no less than 1000 microns over the concrete hearth.

 

[WoodYouLike]

There is no reason not to use an underlay with a built in damp proof membrane on a timber floor as long as there is no underfloor heating.

This is rubbish advice, specially from someone calling himself "floorsave"!

It's a known fact that a DPM on floorboards or any sheet material - such as plywood, chipboard etc - can and most often will cause condensation which will effect the existing floorboards and if you're really unlucky even the joists!

 

[Floorsave]

Hi Woodyoulike,

Just a bit of information for you, My name is Lou Collins i own a company called Jordans Wood Floor Warehouse based in London. This is my 19th year in business selling wood floors. I also owned a floor preparation company for over 5 years. Before that, I was a floor fitter for over 10 years. We sell over 3000 square metres of wood flooring every week and the advice i give out is the same advice that all my sales staff give out and we receive very few complaints. So please if you think you know better, give out your own advice and dont call mine rubbish.

Kind Regards

 

[WoodYouLike]

We've been giving proper and professional advice here since Nov 2004, we are professional wooden floor retailers and installers/restorers, based in Kent.

Your advice on using DPM over floorboard is incorrect and will not "save" the floor

 

[Floorsave]

I'd just like to point out that in a lot of Victorian houses, there are air flow issues where damp air flow gets through the floorboards into wood floors causing them to cup and move. In my experience, we have always checked the air flow bricks to make sure that they are correctly fitted. If they are not, we always use an underlay with a DPM built in. It would be highly unusual for condensation to sit between a wood floor and a polythene backed underlay. Condensation is usually where heat and moisture mix. You would expect this to happen in the room itself but not underneath a block and beam timber subfloor. The only moisture that you would get underneath a block and beam floor would be from the airflow unless of course there was a problem with the damp course of the building.

So I summarise that i can see no problem and never had an issue with putting an underlay with a built in DPM on top of a timber floor before laying an engineered or laminate floor. We would always recommend that damp test reading is made on all surfaces prior to installation of a wood floor.

 

[Lodi]

Well anyway, here is a helpful link for flooring tools.

 

[WoodYouLike]

So I summarise that i can see no problem and never had an issue with putting an underlay with a built in DPM on top of a timber floor before laying an engineered or laminate floor. We would always recommend that damp test reading is made on all surfaces prior to installation of a wood floor.

Most often this advice is given to protect the wooden floor sold and bugger the existing sub/underfloor.

Agree with the moist measurement being taken before installation takes place but we would never ever recommend to use a DPM on any wooden surface, be it existing floorboards, existing parquet floor or plywood