Drylining over plastered walls.

[edenbridge]

I'm about to undertake an extensive renovation on a 1960s bungalow.

The interior walls are badly cracked, and we have had builders in to quote for cutting back and replastering them. The house is to be rewired, and new skirting boards are to be fitted, so this would also be an opportune time to replaster.

One suggested lining the [external] walls with plasterboard, screwing them directly onto the walls with no gap or battens between. This would save time, but also "improve insulation no-end", making the walls "warm to the touch".

Is this true? Apart from making the room slightly smaller, are there any other drawbacks to this approach? Could dampness between the wall and plasterboard be a problem?

Your comments and experiences appreciated.

 

[Richard C]

Dry lining with plasterboard sheets is a quick way of achieving a new finish but if the boards are going straight over the existing, they are normally stuck on using drywall adhesive (dot & dab) not screws! It will improve thermal efficiency but the “no end” tag is a bit OTT if it’s just stuck on without the benefit of additional insulation beneath. Battens are sometimes used with foil backed boards & high efficiency insulation if damp is a problem or increased thermal efficiency is required. Builders generally love dry lining because it’s cheap, quick & you only need someone who can skim rather than a proper plasterer. The downside is that the wall will sound hollow if battens are used or if too large a gap is left between the PB & the wall, it can be difficult to fix anything to & can be easily damaged if something is pushed into it. Damp shouldn’t be a problem unless there is already damp in the wall.

I also have a 60’s property renovation going on at the moment with problems in every room but have the benefit of being able to plaster myself. I’m using several methods, depending on the overall condition of the plaster; most walls have just been re-skimmed after reinforcing the smaller cracks but the larger cracks have been taken back to block work for investigation & repair & in some cases this has involved repairs & wire mesh reinforcing of cracked block work underneath. Other walls were so bad I’ve removed everything & started again, mostly using plaster but in a couple of cases where I wanted to raise the thermal efficiency of a single skin wall or the wall was in bad condition, I‘ve used dry lining with additional insulation & skimmed over that; there have also been some new stud partitions gone up.

If the plaster really is too far gone, the proper way to do it is strip it right back & start again & that would be my preferred option if you can find a plasterer capable & prepared to do it; & be warned that many are not! But it will be very expensive compared to over-boarding & re-skimming & another little gem I found out via this Forum only recently is that if you remove more then 24% of the plaster, the work becomes notifyable to Building Control & you will have to comply with the latest regs. on thermal efficiency with all that could involve. Fine if you don’t tell them but if BC are involved with inspection of any other work your doing & start to get nosey you could get found out!

 

[edenbridge]

Thanks for that, Richard.

I did wonder about the "hollow sounding" aspect, and the added problem of being able to secure anything to the wall if battens and insulation are used. I'll ask again if he plans to screw or glue - maybe I'm getting confused with something else he told me. All the ceilings are to be reboarded, and screws will be used for these.

Once more wallpaper is removed we'll have a better idea about the extent of work required. Building Control will have to be involved with other aspects of the renovation, so thanks for the tip about the 24%!

C&H