We're about to replace the old lath & plaster ceiling. Having ripped the old down we're ready to put the new up. Where's the best place to start? The room measures approx 9m by 5m but, being an old property, it's not going to be square! 12mm or 9.5mm board? Same question for the walls - we're likely going to use dot and dab and again wonder if there's a better starting point? 12mm or 9.5mm board? Cheers John
9.5 on the ceiling will be fine. 12 on the walls. For the ceiling you are governed by the existing joist spacings, if these suit the plasterboard sheets, work it from the middle out to each side giving you an equal cut either side as near as dam it. Walls start anywhere that suits, making sure you don't leave yourself a tiny strip and any end, if it looks like you will, start with half a sheet of plasterboard.
Would use 12mm board, don't butt the edges, instead leave a 3 mm gap. There will be wastage, if fitting yourself you could go for the small boards i.e 3ft x 6ft (90 x180mm). The edge will have to rest on the joist for fixing.
Use 12.5mm boards. Even though it's a ceiling. I'd personally only use 9.5mm for overboarding an existing ceiling.
I took down a a latt and plaster cieling once, its one of the dirtiest jobs I've everdone, the muck spread throughout the house and i could taste and smell it for months, since then I overboard everytime,
If it your own home you may as well put up the blue sound proof board. Full sheets are no problem as long as you have two sets of steps.
Oh yes!! I've pulled a few down over the years and it's probably the dirtiest job one can undertake in the home. Because of damp, we had no option as the ceiling was ready to collapse! Pulling out all those bl**dy nails was no fun either!!