Paint on Vapour control barrier

[dhutch]

Has anyone had any experience/success with such products? Suggestions of brands?

I am getting issues of condesation forming on the underside of the floorboards in my attic now I have increased the insluation from 2 to 10 inches. (raised the joists to accomdate the height, but not enough for an air gap)

One option as I understand it is to replace or overboard the plasterboard and incorporate a vapour barrier above it, or with a foil backed plasterboard. However in one room I have already had the ceiling repaired and skimmed and reboarding this would be undesirable, particularly as I rent the room out.

BnQ appears to be as cheap as anywhere for the gyproc offering.
http://www.diy.com/nav/build/buildi...accessories/Gyproc-Drywall-Sealer-10L-9273303


Daniel

 

[dhutch]

Anyone?

 

[opps]

Hi there

I think that the lack of responses might be in part the result of the less than clear question.

I am concerned that by having no airflow you will potentially make the problem even worse. But I am not an authority on the matter.

Try reading up on cold Vs warm roofs

eg

http://www.delston.co.uk/coldvwarmroof.htm

Additionally you might find posting in the roofing section will get a better response

//www.diynot.com/forums/viewforum.php?f=17

 

[dhutch]

I think that the lack of responses might be in part the result of the less than clear question.

I am concerned that by having no airflow you will potentially make the problem even worse. But I am not an authority on the matter.

Additionally you might find posting in the roofing section will get a better response

Im mainly just after a heads up on whether vapour control paints work and are worth the money and time of day.

I am working to improve/increase the ventilation to the living space below, however its my understanding that I will still get some vapour passing through into the attic space and condensing on the floorboards unless I install a vapour barrier or take up the floor and extend the joists another 2-3inchs to leave an airgap before putting themback.

Daniel

 

[opps]

sorry daniel,

the penny has just dropped, I though that you wanted advice with regard to painting on top of vapour control barriers rather than paints which work as vapour control barriers.

Waterbased eggshell will stop moisture as would Zinsser BIN. if however you have recessed lighting the moisture will still pass through. You will also get moisture travelling up through the loft hatch etc.

 

[dhutch]

the penny has just dropped

Waterbased eggshell will stop moisture as would Zinsser BIN.

Ahhhh, right , yes. Painting something onto plasterboard to form a vapour barrier, rather than painting something onto a vapour barrier.

Others have mentioned using Zinsser, avilable in smaller qualitys, but more expensive per m^2 or even just white gloss intended for woodwork.

There are 'recessed' light fittings in the bathroom, which I may remove anyway as I dont like them, but the condensation appears to be worse over the bedrooms so they are certainly not a only consideration.


Daniel

 

[opps]

You wont want to sleep in a room that has had that much OB gloss applied for a day or two.

WB eggshell or BIN, virtually no smell after an hour or two.

 

[dhutch]

You wont want to sleep in a room that has had that much OB gloss applied for a day or two.

WB eggshell or BIN, virtually no smell after an hour or two.

No, and thats a valid point as well.

Sounds like its worth having a go then anyway, with BIN or simular.

 

[opps]

You wont want to sleep in a room that has had that much OB gloss applied for a day or two.

WB eggshell or BIN, virtually no smell after an hour or two.

No, and thats a valid point as well.

Sounds like its worth having a go then anyway, with BIN or simular.

WB eggshell should be the cheaper but it will have a sheen, the sheen level will vary from brand to brand. The Farrow and Ball Modern emulsion will also work and is much flatter, there are other scrubbable emulsions available.

I love BIN but it is so thin that it will splatter much more, it (really) stinks of alcohol which goes after an hour or so.

The degree to which any effective barrier will solve your problem, not so sure, can you not drill a series of holes in the floor boards to aid airflow in the short term? Or Kingspan the roof, whilst still allowing airflow under the tiles.

BTW OB paints would yellow in time, BIN and WB wont

 

[freddiemercurystwin]

I've specified this before where a brush applied VB was required. http://www.restorationuk.com/epoxy-resin-flooring-coating-paint.html

 

[opps]

I've specified this before where a brush applied VB was required. http://www.restorationuk.com/epoxy-resin-flooring-coating-paint.html[/QUOTE]

The OP is looking for a way of preventing floorboards in the loft becoming damp on the underside, not in his garage...

 

[freddiemercurystwin]

I've specified this before where a brush applied VB was required. http://www.restorationuk.com/epoxy-resin-flooring-coating-paint.html[/QUOTE]

The OP is looking for a way of preventing floorboards in the loft becoming damp on the underside, not in his garage...

And if you knew anything about the product you would know that's exactly what it will do.

 

[dhutch]

And if you knew anything about the product you would know that's exactly what it will do.

Painted onto the plasterboard of the ceiling below? Underside or top side?

 

[freddiemercurystwin]

On to the underside of the plasterboard. It will act as vapour barrier.

 

[dhutch]

On to the underside of the plasterboard. It will act as vapour barrier.

Fair enough.

I assume its quite thin then, more of a posh fully waterprood version of pva floor sealer, than an epoxy/leveling paint.

Not that its cheap!


Daniel