Filling Painted Render

[tony1066]

We recently had a gable end 'smooth' rendered by an experienced plasterer. After the job was finished I painted it with Sandtex masonary paint. It was only after painting that it became apparent that the plasterer had not made a good job. There are lots of smallish holes and blemishes. Now, the question, is there a 'filler' which would be suitable to fill in the blemishes etc, remembering that the surface has been painted, or will I need to remove the paint first!!

 

[roughcaster]

Tony,
This is only my opinion. Sometimes you can make the render look a lot worse trying to patch it, especially outside when the sun shines across a wall/gable. When you say "smooth render", i'm taking it that you mean a sponge finish, which is the more common way,as opposed to a troweled finish. Cement render has it's own texture and when/if you try to patch it with a "filler" in "lots of places", you might wish you had left it alone.... Anybody else?

Roughcaster.

 

[Micilin]

Tony,
This is only my opinion. Sometimes you can make things look a lot worse trying to patch over things, especially outside when the sun shines across a wall/gable. When you say "smooth render", i'm taking it that you mean a sponge finish, which is the more common way,as opposed to a troweled finish. Cement render has it's own texture and when/if you try to patch it with a "filler" in "lots of places", you might wish you had left it alone.... Anybody else?

Roughcaster.

I'd be inclined to agree. It is very hard to patch render and make it look good, you might only be drawing attention to the bad spots.

For patches like that I would use silver sand and cement mixed with SBR, having primed with SBR, then sponge up to match. It will be hard to match the texture, especilly now it has been painted.

You could consider using Hi Build . I don't like the stuff myself, but it is apllied with trowel or roller and finished with a special roller as the one here

http://www.contractbeads.co.uk/products.asp


This will give you a textured finish, to cover over the render. It should be okay to go over the paint (many jobs paint the render first to slow down the suction) , but that is something you will have to check with the supplier.