painting a garden wall

[alisonbayne]

I have just rendered a small garden wall with sand and cement mix. I wish to paint it. Do I need to treat the rendering with anything before painting? Thank you.

[moonacre]

You don't have to but its advisable. Bare rendering is very absorbent so if you just paint onto it then it will absorb the paint too easily. This means it may take many coats to get an even finish and the surface will be prone to weathering. You can buy purpose made sealing stuff which you can paint on first. Or you could buy some ordinary white PVA glue and mix it 1:3 with water for pretty much the same effect but cheaper.