Plasterboarding a wall

[aneray]

I live in an end terrace house which is about 45 years old. My sons bedroom which is at the end with an outside wall suffers from a lot of damp/condensation for a lot of the year.
We have now fitted new facias which will help solve the problem but I am considering adding a second layer of plasterboard to the two outside walls which will help keep the heat in.

My question is " Is there anything I could paint on or cover the walls with before plasterboarding to keep out the damp and affecting the new board ? "

Thanks Neil

[The Builder]

fix 25mm thick treated battens to the wall at 400mm centres......... fit 25mm "celotex" insulation between the battens ........... nail plasterbaord to the battens and skim (plaster) the board.
..........insulated ................. done :o)

[aneray]

Builder

Thanks for the reply, it was very much appreciated.

Through past experience, the outside wall is an absolute pain in the backside to drill through, so I thought that instead of screwing the batons in to place I would use No More Nails Ultra to stick them. Even thought it is a great adhesive, would it be strong enough to hold the weight of the plasterboard and plaster considering I am boarding all the way down to the floorboards.

Hopefully a final question if I may

Can the insulation that you mention be bought in any builders merchants here in Cornwall and I assume it is 25mm thick.

Once again thankyou

[The Builder]

..right ............. sorry for the delay ............... been to the pub hic

yes, a decent high grab adhesive would take the weight............ but don't forget the glue is only as good as the substrate (surface you're sticking it to)......... if it's wallpaper for instance, then you'd need to remove that first........... if the plaster is good, then it'll hold.
The insulation is available anywhere ......... even in Cornwall (I'm in Devon)............... a cheaper option would be polystyrene - but not so good at insulating.
The insulation is in sheets 2.4m x 1.2m

[aneray]

Once again much appreciated for your reply ( the pub sounded good but here in Camborne there a waste of time, too many little chavs on scooters !!).

The substrate is fine and by doing it the way you said will save me so much time sanding the walls to remove every blemish before painting.

As you are also in the South West you will know how very damp it gets down here so this should solve all the problems.

Thanks Neil

[tezestwing]

aneray the construction is more than likely to be solid wall (not cavity) and plaster could be old browning or similar and skimmed this combination spells disaster in old properties it thrives on moisture it wicks it through from the outside.
I suggest that all this old plaster is removed then batten out and trap a DPM (polythene) to the bricks and then do as the builder has posted and fix using plugs and anti rust screws into the mortar joints, not billy no nail.
hth Tez

[aneray]

tezeswing

Thankyou for your reply

My home has got a cavity wall because I had it insulated a few years ago. I did take note about what you said about using plastic sheeting to keep out the damp

I will be taking both your advice on the project by using the plastic, batoning and insulation and hopefully will keep out the damp

Cheers Neil