When it comes to the plaster in the house it’s a mess, near enough all the ceilings are failing (the old lathe and plaster ceilings) and many of the walls that are plaster, not plasterboard have problems due to years of neglect. Even some of the newer drywall walls aren’t up to standard and need work!
I’ve never plastered or used drywall/plasterboard before, closest to plastering is filling the odd hole with polyfilla, so I had no idea how hard/easy plastering could/would be. So we prepared a small wall, bought some one coat plaster from Wikes (10KG bag) and I tried to plaster a 4 foot square test area.
Plastering for the First Time
I’ve read about plastering, but reading and doing are two different things. Mixing the plaster was easy, getting it on the walls was easy, but getting it smooth was hard. Turns out I made the plaster to wet, so when going for a smooth surface it left ridges on the edge. I also fell into the trap of not leaving the plaster to set a little, just couldn’t leave it alone so over worked it!
Not one to give up after one try, bought some more plaster (multi-finish from Thistle) and tried again, this time adding less water. Again I did a small unimportant test area and again I made the plaster too wet (not as wet as before though). It was easier this time, but it was still too wet to get a good finish (quickly learning though :-).
I mix up another batch of plaster, this time Cameron (eldest son, whose 14) thinks he can do better (kids hey :-)). So we make the plaster not as wet and we split the bucket between us. The plaster goes on better this time, even Cameron did a better job than my first two tries (I was so proud or was it irritated :-)).
At that point I could see we had the basic skills to do this, since even with the wrong type of mix (too wet) the finish wasn’t that bad. I wasn’t happy with the finish, but I could see we could with practice get the house plastered to a high standard. What we’d learned though was the most important factor seems to be getting the mix right and not spending too much time on an area (you end up over working it).
That was a few days ago.
Just Call me the Plaster Expert, NOT!
Yesterday we went to the house with the aim to only plaster. We decided on one of the attic rooms, theory being they should have the best finish for us to work with since they are a relatively new addition to the house (I was wrong).
First we checked the stability of the current plaster, on one of the walls the plaster skim that was probably 20 years old was very easy to remove from the wall. Using a basic wallpaper type scraper we could scrape of large areas of plaster in seconds. The image to the right (it’s the left wall we scrapped) is how it looked before we started scraping.
In one area behind a wash basin we’d removed earlier there was unstable plaster, we took the loose bits back to the wall. So there were no unstable areas of plaster. This left us with a fair sized hole (see right).
What we found beneath was the original plaster with the remains of a blue paint (possibly emulsion) that had degraded over time (it was powdery). When we scraped the plaster skim off some of the blue paint stuck to the wall, the rest on the falling plaster (image right). So the failure was due to the paint layer. I’m guessing the professional plasterer who did that wall didn’t PVA it prior to adding the skim (there are other walls in the house like this, so we have a big task ahead of us!).
So we scraped off the loose layer, removed anything that wasn’t secure (to the brick work if needed), gave it a good brush to remove dust etc.. and PVA’d (4:1 ratio) to improve adhesion of the plaster.
The first bucket of plaster we mixed we again made it a little wet, but it was very close to what we have now found to be the right amount of water. It went on easily, but because it was still a little wet we had the ridge/lines problem, though as the plaster dried on the walls we could remove most of those.
I have to admit Cameron’s finish at this stage was better than mine (I hate him now :-))
Next bucket was spot on, went on easily, spread easily and it didn’t leave lots of ridges/lines. Our finish still wasn’t brilliant, but I’ve seen much worse at the house we live in now that was a new build 5 years ago with professional plasterers etc… I’m very much a perfectionist, so I’ll never be completely happy with anything like this where perfection through out a project is practically impossible, but can grit my teeth and move on (just).
We decided to make a bucket of plaster each for the next batch, Cameron’s was spot on so he got to work plastering. I added too much water to the bucket, so had a full bucket of plaster that was really difficult to mix. We had been using a mixer attached to a cordless screwdriver/drill, but the batteries ran out on the last batch, so it was down to manual mixing (that is hard work!!). I eventually got the plaster mixed and started to work.
Cameron was working on a sloping area and was having problems (not sure why), he didn’t get to use the whole batch, so wasted about half a bucket (I’ll take it out of his wages, well I would if I was paying him :-)). He did quite a good job with that section (see right). I managed to use around 90% of my plaster and learned another valuable lesson. The easiest way to plaster is slap it on quickly, give it a very quick smooth and move to the next bit. 10 to 15 minutes later go back to the first bit plastered and finish it off (it’s much easier then). This technique worked a treat as in no time at all I’d finished the rest of the wall and was smoothing out any problem areas.
This is the first wall we’ve completed and I’m 90% happy with it, will probably touch up any problems next time when we are doing another wall.
Now we need to learn to plaster quickly, so we don’t take 9 months to plaster the house :-)
Update on this, we are finding the dried plaster isn’t quite flat (very close though), having to sand down areas, so still need more practice.
How to Drywall
After plastering several rooms I’d got to grips with plastering, I’m not a professional plasterer by any means, but the job is good enough, even for a DIY perfectionist like me!
Since a LOT of walls have very poor quality plaster and the entire basement had a plywood type covering (fire proof plywood, very thin) that was damp since the idiots who fitted it had actually laid the bottom of the wood directly on the concrete floor which meant over the last 20 years there’s been a lot of water damage, we’ve had a lot of bare walls to deal (so no plaster on them).
I figured it would be easier to use drywall (or plasterboard as we call it in the UK) so bought some sheets of drywall from B&Q.
I tried the dot and dab technique, but after wasting half a dozen boards (not fully wasted, scraped the plaster/glue off the back to recover them) I couldn’t get the damn boards to line up correctly (not something I expected to be hard!).
In my experience dealing with drywall/plasterboard is harder than plastering, but it is faster when dealing with bare brick walls and when done right the finish is better.