There are things that take a lot of time to finish, and seem like barely any progress at all (removing glue from underneath the carpet anyone?). And then there are things that don’t take that much time but have a huge impact on how a given room looks and feels. If your walls are made of brick (and not drywall), then plastering them is one of those things.
But first, some music. Kudos if you guess the link (go wild in the comments, I dare you).
How did we do it?
So, plastering brick walls. It requires some patience to set up and finish it properly. It requires a certain level of handiness. But once you get the hang of it it really isn’t that hard.
First of all cover up your floor! Unless of course your floor is going to be changed afterwards (which is recommended, but we failed to plan so).
Yea, I recycled the packaging from the insulation…
You need some gear. Like a mixer and a mixing tub, to mix the plaster in it. Crafting the perfect mixture is quite easy: dump a bucket of clean water in the mixing tub, and then a bag of plaster (in powder form, we used Knauf MP75). Wait a little bit (a minute or so) to let the plaster powder soak up some of the water, then dump in the mixer and start mixing! If you find the mixture isn’t getting fluid enough, add a little water. Be careful though, as it can be too much really fast!
With your mixing tub full of plaster, it is time to start the preparation. You’ll need a trowel to scoop up some of the plaster, and create a nice vertical line about every 1.5 to 2m on the wall. Make sure it’s thicker than the amount of plaster you’ll eventually need on the wall, as you have to push an aluminium profile into it:
Now you’ll need a level. A large one. The larger the better.
And now for something tricky: make sure the profile gets level, while getting it as close to the wall as possible. That way the final layer of plaster is as thin as possible, preferably less than 2cm anywhere. Realistically, especially in older houses, you’ll end up with places that have 3cm or more of plaster thickness. So do we. So be it.
Anyway, now you have two of these profiles, looking kind of like this:
Let it dry for a little bit, so that you need some force to move them. Now let the fun begin! With your trowel, throw plaster against the wall until you’ve covered a lot of the surface between both profiles. Then take an aluminium straightedge, and let it slide over the two profiles, scraping all excess plaster off the wall. This works best if you go up in a zig-zag motion, and dump the excess plaster back in the mixing tub every once in a while.
One mixing tub will probably not be enough to cover just this part (depending on how wide apart the profiles are and how high the wall is), so you’ll need to prepare a second one. And a third one.
Now you can move. I’d suggest you start near a corner, so you can now remove the profile the closest to that corner, and finish the wall up into the corner as above: fill with plaster, scrape of the excess (this time using the first plaster as a guide, so be careful). Then you can proceed along the wall to the other corner:
- place a new profile and level it
- fill up in between two profiles
- scrape of the excess plaster
- remove the profile completely surrounded by plaster and fill up the little gap
The tricky part here is that the longer the wall, the better you need to look out for your plaster to stay straight horizontally. As our wall is only 3m wide we didn’t really have a problem here.
Every five or ten minutes you need to check on the plaster: as long as it feels wet and sticks to your finger, you can continue the above. Once it doesn’t anymore, it’s time to make sure your mixing tub is empty, as the next phase needs to begin (and by the time you’re done with it the plaster in your mixing tub will have dried out anyway).
Now you’ll need a sponge and (yet another) bucket of clean water (did I mention you’ll end up using a lot of water when plastering?). With a wet (but not soaking) sponge, go over the plaster (that doesn’t stick to your finger anymore) in circular motions. That way you get a very small layer of the plaster wet again.
Then take your taping knife (yes, another piece of gear) to go over that part one final time. Try to keep it as perpendicular to the wall as possible, and smoothen everything out. You’ll need to use some force for this to get a really nice and smooth result, and you’ll possibly have to go over some areas more than once. Just remember, this step determines the end result.
As a tip: check if your taping knife is slightly bent at both edges. If not, try to give them a little bend in the same direction. That way you’ll prevent small dents in the plaster when putting your knife against the wall.
If you come across an outer corner, you’ll need another kind of profile:
Everything stays the same as above, except that you don’t remove it this time. It will protect the corner from damage when you bump into it. Your best bet is to make it as close a fit as possible, whereas for the regular profiles you have some margin.
When you’re all done, make sure to give it enough time to dry out. Depending on thickness of the plaster, temperature and humidity, this could take a month or more! Remember all that water you put into the plaster? That now has to come out again…
How does it look like?
Well, white. Dirty white though…
And remember those boxes for electrics I put in some time ago? They stuck out around 1.5cm, and now they’re nicely level:
The room is finally starting to feel like a finished room again! There’s still a lot to do, but at least we don’t have to look at those ugly bricks any longer!
Anyone up to share his or her plastering work?
Featured image credit: David Gunter.