Dry Lining External Walls Ask your questions and find answers on many subjects relating to plastering and dry lining

[joe7]

I am looking at options for improving insulation in a solid brick external wall. The property is a 1930 semi with solid brick construction. My thoughts are battern wall and fix Kingspan K7 board which has plasterboad, 60mm insulation and vapour barrier all in one. Questions I have are:

1) Can the batterns be fixed to the existing wallpaped walls or should I strip the wall back first to remove the old wallpaper?
2) I have read the batterns shoud be treated but not sure what this means do I buy battern pretreated and if so what are they treated with?
3) Does dry lining need Building Reg approval?
4) To avoid impacting the size of the room too much, on the external wall with the chimney breast I was thinking of only dry lining the two recesses, does this make sense or should I dry line and insulate the chimney breast as well?
5) Is there another option you think I should consider?
6) I am also thinking of plaster boarding the ceiling in the house with 9mm board as existing ceilings are papered or have polystrene tiles. Should I remove the old ceilings lathe and plaster and decorations or is it standard practice to just dry line on top of the existing decoration?

[alanthomaswatson]

joe7
Responses below:

Firstly I presme you mena K17? K7 is a roof insulation board.

1. It's up to you, but remember that behind the old wallpaper will be old plaster which if it's been there a while probably won't provide a good fix. In doing the same job myself I've done one wall after removing the plaster complete and one only in part where the plaster crumbled off. It's more messy and you have to 'pack out' the battens to get a plumb edge but I find removing the old gives a much better result. Removing the old plaster will also mean you encroach less into the room.
Also, have you considered 'dot and dab', i'e adhesive fixing - this helps massively in compensating for out of true walls and means you aren't puncturing the vapour barrier.

2. You can buy pre-treated battens at Wickes, B&Q etc. Example on this link: http://www.awin1.com/awclick.php?mid=15 ... nvt/107136. I use the 25mm as I use a 'built up' method and install polystyrene insulation between.

3. Doubt it. You're not making any structural alteration and are improving the efficiency of your house.

4. I'd dry line and insulate the chimney breast as well - remember the chimney breast is essentially a void of cold air - if you insulate just the sides the chimney may become the coldest part and you could end up with condensation on the walls. Now is a good time to check the fire place is ventilated through with an air brick.

5. As noted above I remove the old plaster, batten out, pack polystyrene insulation, fix a damp proof membrane and then fix, tape and fill plasterboard sheets. It does take a while but adds lots of insulation and has significanly warmed and cured condensation patches in two bedrooms. However I did look at K17 but couldn't find anyone to deliver to my area.

6. Again, my preference would be to remove the ensure the best fix to the joists, but other more experienced plasterers may disagree.

[joe7]

thanks for your thoughts
joe

[TheDoctor4]

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