Huge wrote:
On 2007-10-29, Stuart Noble wrote:
The Natural Philosopher wrote:
Stuart Noble wrote:
The Natural Philosopher wrote:
TWEEZER wrote:
I have just had the outside of my new kitchen extension sand/cement
waterproof rendered. I now want to paint it with exterior emulsion.
What is the process for painting new render.

Put brush in paint and move brush up and down on wall?

i.e. nothing special., HOWEVER if the wall is subject to driving rain
and heavy frost, consider using a waterproofer first. I got SOME
spalling on a new render wall where the rain was 'bouncing' off some
lead topped window frames, soaking into the render and freezing -
this on a dank north west facing wall.

Thanks

S/SW facing is the most vulnerable in the long term. A solvent based
pliolite paint from e.g. Johnstones would be a better bet than
ordinary masonry paint. Expensive, but well worth it IME
Only from UV degradation, but IME that is not an issue with modern paints.

Looking at the houses round here, all S/SW facing windows are shot to
pieces, or have been replaced. Opposite side of the road, mostly
original woodwork.

Quite. The lifetime of paint on the windows in S/W facing rear of our house was
about 18 months, no matter how carefully it was prepared and what paint was
used. I gave up and had uPVC instead. The masonry paint lasts quite well.



IME standard water based masonry paint is mainly cosmetic. It survives
if the masonry itself is in good nick. The pliolite stuff is better on
degraded render and IME is very effective against penetrating damp.