Correct way to paint smooth cement render? Internal / External

[devs]

Hi guys, I've recently built a large garage outside that has been finished with smooth cement render both inside and out. I just wanted to know the correct way to paint this after it is finished drying out.

I plan to use sandtex masonry paint for the inside and Dulux Weathershield for the outside.

Any advice would be great.

Thanks

 

[sparkwright]

You could dilute the first coat with water, to ensure the paint bonds to the surface well.

 

[devs]

Thanks, I've bought some cheap paint to dilute down. Would you do 50/50?

 

[JohnD]

I do. Cement render, and concrete, are very hungry and absorbent. You will probably find the first thinned coat is sucked into the wall and disappears. Apply another thinned coat.

When the wall stops sucking your brush dry, it is primed enough to start painting.

Rather than buying cheap paint, consider buying a good brand in white or magnolia, which are the cheapest readymixed colours, for the mist coats.