Today we will cover you how you can do your very own patch plaster work.

Tools and Materials required 

  • a small paintbrush with some premixed adhesive
  • a filling knife
  • plastering trowel
  • a hawk
  • and some premixed plaster.

crack in plasterWhen you are doing repairs on very old houses you might come across a thing called lathing plaster, and that is where you get quite vulnerable breaks in the wall like this.

The nature of it is it has got two studs coming down the sides, then you have got the lathe witch is the small battons which bridge across. They are nailed in.

And then of course its all rendered or plastered over with a thing called wattle daub. What that is, is a general mixture of various different local materials, from horse hair, to lime putty. It is all mixed together, even clay in there, and it is spread across it.

scrape away loose plasterThat was fine hundreds of years ago but it is starting to break away and get brittle now. To do a repair you must get yourself a scraping knife and break away any of the loose areas off here top start with. You have to be quite delicate when you are doing this because the more you take away the more loose it starts to become and the more you are exposing the little lathes of wood, and they are starting to bounce a little bit as well.

apply bonding agentSo once you have cleared away all of the loose areas, get your paintbrush and apply this premixed sealant over there. This is like a bonding agent, and what that will do is absorb into all the loose areas and stiffen it up a little bit. Of course it will help our new plaster key to that. Once you have covered the area, leave it for a couple of minutes to start to dry.

Once it is tacky you can then apply the plaster. 

apply plaster to wallNow that has had a couple of minutes and it is more or less touch dry, it is ready to apply your plaster. I’m going to get my small trowel and my hauk, I have got my lightweight plaster. I’m going to start by getting the end of the hawk and a good fair bit on the trawl itself. Now of course I don’t want it to fall in-between all of the slats there, I just want it to grab alongside it and hide it. I am going to put a lot more on than we actually need at this point.

Shake the trawl a fraction, which helps it get in-between all the little gaps in there and avoids any air pockets. Again, at this point you don’t have to worry about what it looks like, you have just got to concentrate on getting enough material in the gaps. Once you have applied enough on and it is standing quite proud from the actual wall surface. Next I am going to place the trawls over the center of it and I am going to just very slowly slide it up and down a fraction.

What that does is just cut away a little bit of the top surface of it thats not required. Making sure your trawl is quite clean to do the opposite side. By cutting it away like that to make it flush with the actual existing surface of the wall. You don’t have to worry about it being smooth at this point, just getting the right amount on. Once this is dried off you can get a tiny bit of a thin coat more and leave it to fully dry, until the following day we can sand it down and it is ready to paint or wallpaper.

Now your patch plaster work is dry it is ready to be sanded down. Now sandpaper comes in different grades, the lower the grade is the more course the sandpaper is. So you start off with a courser one then you work your way down to a more finer one to get a nice smooth finish.

Now if you have got a lot of areas that needed patch plastering, you are going to have to sand a lot of areas down. It is worth investing in a good electrical sander, I find palm sanders perfect for rooms this size. If you are planning any DIY tasks in the near future, you may need a little bit of advice on tools or some top DIY tips drop me a message for help.

How to Patch Plaster Walls