8 Things you Should Ask your Plasterer

What should you ask your plasterer to ensure that they’re an expert in their field? The plastering trade is a complicated one, so it’s always best to get a qualified professional to do plastering for you.

Here are 8 things that you should ask your plasterer. If they’re good enough, they should be able to answer them.

1. At what thickness will you apply my plaster?

This is a tricky one to start with, but your plasterer should be able to answer it. Usually, undercoat plasters are applied at around 11m thick for walls, 8mm for ceilings and finish coat plasters are usually 2mm thick.

Some one-coat plasters are applied at 13mm thick for walls or 10mm for ceilings. But you might not want to employ a plasterer using one coat – read our blog post to find out why.

2. What plaster would you use on sand and cement undercoats?

Ask your plasterer this question and they should say that it depends on the suction level of the background material. There are different brands out there, but they may suggest a product like Thistle Multi-Finish or Durafinish.

3. If salt contamination happens, how will you deal with it?

If salt is brought to the surface of the background, the plasterer should remove it carefully. The background must be clean and free from dust. If you’ve got a lot of salt contamination, it can cause damp problems. The plasterer should work out whether the salts are from the drying process or are the result of a wider damp problem in your home.

4. What plaster would you use after I’ve had a damp proof course installed?

You’ll need cement-based plaster if you’re re-plastering after a damp proof course.

ask your plasterer about plastering on a damp wall
A damp wall needs to be treated before it can be plastered.

5. Should you plaster a damp wall?

Ask your plasterer this and they should answer no, not if the wall has rising or penetrating damp. If you just have some dampness left after you’ve had a damp proof course fitted, this should be fine.

6. Can plaster help reduce air leakage?

Yes. You can maintain airtightness by plugging gaps and cracks with the right plaster.

7. How should you plaster a painted wall?

Ask your plasterer this. If they know what they’re doing, they should say that only a painted wall in very good condition should be plastered. If you want them to plaster over a painted wall, they should offer to do it on a trial area first to see if it’s suitable.

8. Can plastering help buildings be more energy efficient?

Some plasters are great for helping properties keep more heat in, meaning you could save money on your energy bills.

So, ask your plasterer the questions that are relevant to your project and see how they fare. You will soon be able to tell the difference between the plasterers who know their stuff and those that are just looking for a quick buck.