DIY Doctor UK DIY Forums

I have an awful looking garden wall that is sound. Previous owner of the house painted it very badly and the edges of the top bricks are chipped. So I am thinking about rendering it to inprove the look of it. I basically have a few questions:
1. How should I prepare it? Knotted wire brush on the drill to deal with the paint?
2. Should I fill the pointing first to bring it out to the level of the bricks before rendering it?
3. Will I need to PVA the wall first?
4. How do I repair the chipped edges? Metal beading?
5. What is the ideal mixture?
6. How many coats should I be aiming to do? Does the mixture change between coats?
7. How much materials will I need for a 4"x15" wall?

Thanks, Chris

Hi Chris
You need to try and strip as much of the paint of as possible, Then you will need to make a key for the suction for your render, the cheapest way to do this seeing as you have a drill would be to put holes in the bricks say 2 holes each brick, they don't need to be to deep.

Fill in all pointing first. when set then you need to apply pva mixed with water to the wall, make sure you do in two coats.
For your chipped edges use Metal angle beading.
Your mix depends, i would recommend 70% cement and 30% sand ( do not use sand that contains clay ) Also add plastersizer.
I would recommend doing the job in two coats.
If you need anymore advise on how to apply the render give me a shout and i will explain to you.
Hope that helps Leigh.

Only add the specified amount of plasticiser as too much weakens your mix. See our project on mortar mixes. Plasticiser entrains air into the mix which allows it to be more workable. If too much air is in it little air bubbles form, unseen, in the render. These eventually fill with water which freezes when its cold. This action is called freeze thaw and can be seen in our freeze thaw project. It is why render and bricks blow off the face of a wall in the first place. Also, applying PVA to a wall will stop it breathing which will not allow any damp already in the wall, to escape. There is absolutely no point in putting any lime into a wall which has been PVA'd as no moisture can evaporate through the render because it cannot get out of the wall in the first place,