I had a serious problem to contend with this week: I was installing a new kitchen, and once I stripped out the old one, an unexpected problem reared its ugly head!
The property was only a few years old, and instead of plastering the walls, and setting with a finished coat, in the traditional way, the concrete block walls had effectively been dry lined. This process is achieved by mixing a dry lining adhesive, and slapping big dollops onto the wall, and then squeezing 8ft by 4ft sheets of plaster board, on top of the dollops of adhesive, and using a long level to make sure its plumb. When its gone off, the joints are taped and filled, and rubbed smooth when set. Once painted it looks great, except it doesn’t have a hard, water resistant finish, and you can’t scrape wallpaper off it.
If you want to hang a picture or build a set of shelves to take any kind of weight, you’ll face a considerable challenge. Why? I here you say, and any of you poor unfortunates who have found yourselves in that very position will know just what I mean.
Regular plasterboard is 12mm thick, the void behind the plasterboard varies from 10mm to 25mm, or even more if the block work is out of plumb. So let’s say a 20mm void plus 12mm plasterboard, will mean using a 50mm screw, which will only allow a maximum anchorage of 18mm, so depending on what’s expected of the fixing, you may have to use 60mm screws or longer, in order to achieve decent anchorage. If it’s a dry lined stud partition wall, you will have to cut out a section of the plasterboard, fix timber or plywood behind the plasterboard, and then patch back in the plasterboard and make good with filler, in order to create decent “grounds” for fixings.
Personally if it’s major alterations, requiring good anchorage, my recommendation would be to demolish the flimsy hollow tin stud work, and replace it with good old fashioned timber, and then you can kiss good night to the problem!
Getting back to me! I ripped all the dry lining off the walls, but had to use a light weight Hilti hammer drill with a purpose made wide bladed chisel, to remove the adhesive. Once that was done, and rubbished cleared, I renewed all the electrics and plumbing for the kitchen, then re-plastered the walls using sand and cement render, with a plaster finish. I was so much happier with that, and I could hang the titanic off that wall, and I would only have to use normal size screws and plugs! The moral of this story: plan for the long game, it will save you tonnes of time and angst in the short term!