Plastic membrane in timber frame house

TKK

While fixing a few holes left in the walls by the previous owner I have found a thin clear plastic sheet between the plasterboard and the studs on the external block wall. This has a number of holes in it as a result of the original holes made. I have not improved the situation in one particular spot where, not knowing it was there (a hole in the sheet facing the hole in the plasterboard), I cut through it when cutting out a section of the plasterboard as part of my repair.

I'm wondering if there is anything I can/should do about the holes?

CJhaughey

The membrane is the Vapour Barrier, It should ideally be uncut but in practice it will usually be cut when sparkies fit switchboxes etc in external walls, try and repair the damage with duct tape or wide sileage bale type tape if you can.

Mellor

CJhaughey wrote:

The membrane is the Vapour Barrier, It should ideally be uncut but in practice it will usually be cut when sparkies fit switchboxes etc in external walls, try and repair the damage with duct tape or wide sileage bale type tape if you can.

Its more likely a vapour control layer than a vapour barrier. luckily holes in barriers are a much bigger deal than control layers. Try to mend the layer the best you can as described above.

yop

It is a vapour barrier alright, I have a TF house and confirm that this the term used by our supplier.
As the lads said you have to try and seal it as best you can. Ideally in a new build you have to tape around the barrier where the sparks have cut but not everyone does it.

TKK

It seems very light for a barrier. I'll try to patch it up as best I can so.

Mellor

yop wrote:

It is a vapour barrier alright, I have a TF house and confirm that this the term used by our supplier.
As the lads said you have to try and seal it as best you can. Ideally in a new build you have to tape around the barrier where the sparks have cut but not everyone does it.

There are many different names for these kind of sheets, such as vapour barrier, vapour check, vapour control layer, breather membrane and water poof membrane.
They are all slightly different and their properties dictate where they should be used.
A vapour barrier, as the name suggests, prevents the passing of airbourne moisture.
A vapour control layer, controls but doesn't completely stop the passing of moisture, it lets a small amount pass through, a low enough level that it can exit the wall without interstitial condensation.
Barriers are used in certain areas where the vapour may not be able to exit.
In a normal wall a control layer should be used so that excess moisture in a room can slowly pass into the wall and quickly leave through the external breather membrane. Keeping the wall dry. If the vapour cannot leave it will condense on the walls, causing damage and possible growth.
Suppliers may generalise and use one name for a group of layers, but I hope they gave you the right one.

Viking House

OSB on the inside of the timber frame will control Vapour when you tape the joints.
The OSB is then cross battened by 2X2's and then plasterboarded to keep it out of the way of the electrician.