Surfaces to render on (surfaces on which to render)

[WabbitPoo]

Apart from masonry walls, are there board alternatives that will accept sand and cement render (exterior)? If so, is there much prep required or can I screw the boards to a timber frame and crack on? Its for a 3.2m long parapet wall, 5 courses high.

 

[John D v2.0]

You can get exterior cement board which you would have to mesh scrim and fill somehow for the base coat otherwise it might crack between the joints. Id have thought you'd need a decent number of screws around the edge if you're fixing it that way

 

[tomfe]

Cement board, you can go over OSB and ply with EML.

 

[WabbitPoo]

so, mesh on anything, then? Cant I just render onto cement board? Thanks, by the way!

 

[John D v2.0]

Yes but you're going to have joins. The mesh I'm referring to is just a cheap kind of fabric mesh to stop slight movement at joint putting stress on the cement render
Eml is a metal mesh to hold the render in place where the whole surface behind may nice independently of the cement eg timber.

 

[^woody^]

Render on a parapet is bad enough. Render on a board is worse, and render on a board on a timber frame parapet is asking for trouble.

 

[WabbitPoo]

thanks. I have decided to do it in lead instead.

 

[tomfe]

A flexible render will be fine. Base coat with fiberglass mesh and silicone top coat.

 

[bobasd]

op,youd be better adviced if you post photos of both sides of the parapet.jumpin from one material to another wont do it