Best product for killing moss on rendered wall

[muff13]

We have a cement rendered retaining wall around our garden on which moss has grown. As we wish to paint this with Santex we were wondering if anyone can recommend any spray to kill the moss before painting. Unfortunately some of the wall is north facing so never gets any sun and is cold and damp for a large part of the time. I have scraped off as much moss as I can but it is obvious that the roots are still there ready to regrow.

[New Judge]

Give it a wash down with Jeyes Fluid.

[condor66]

just done our drive with hydrochloride bought from farm supply shop, farmers use it for cleaning out milking parlours,,, it is brilliant at getting rid of moss.

[muff13]

Thanks - hydrochloride sounds to be the best bet if I can get hold of any. No dairy farms around this area I fear as live in the wilds of Scotland.

[heathfield]

Wherever you're buying your Sandtex from should also stock Sandtex Fungicide. It's what Sandtex recommend in your situation. But it is more expensive than several suitable alternatives. Google for 'algea moss killer' and take your pick.