Q: My backyard consists mainly of a concrete slab patio and a retaining wall made from concrete blocks. It’s so gray that even the trailing rosemary and bougainvilleas I’ve planted look washed out.
I was considering painting the patio with thinned-out paint in a terra-cotta color (something to coordinate with the painted stucco on the house). Would this be a viable option or something I should leave to the professionals? How would I make sure that the paint wouldn’t wear off? I’ve seen patios painted before where the paint starts to peel and bubble.
A: It’s time to put a little color in your life, and you can do it yourself — no pros needed.
The thinned-out paint look you’re after will be handsome. The color and texture will not be uniform because your patio concrete is porous. You’ll get a mottled effect that we think is attractive.
Your reservations about painting the patio are well founded, as painted concrete ultimately chips and flakes. Once the chipping process starts, there’s no stopping it. Unless the patio was poured over a vapor barrier — which is almost never the case — groundwater migrates up through the slab via capillary action. The sun bakes the surface of the concrete, causing the moist concrete underneath to warm. The bond between the paint and the concrete breaks, and the paint flakes off.
Painted concrete can also be a safety hazard. It’s slippery. A skid-resistant surface can be achieved by adding fine sand or crushed nutshells to the paint. But it’s difficult to get a uniform finish with these additives.
Many manufacturers have taken this a step further, adding various types of aggregate to create textured epoxy paints. This makes application easier, but the flaking problem remains.
We think you’re on the right track as to the choice of materials for the effect you want. But thinned-out paint isn’t our material of choice. What you want is a concrete stain.
Although you don’t mention painting the cinder-block wall, we recommend that you paint the wall to provide a completely finished look to your backyard. Concrete staining and block-wall painting are two separate processes. Here’s how we’d approach each:
Last summer Kevin spent some time with a representative from Duckback Products, a Chico, Calif.-based company. At the time he was researching a story on decking and was interested in its products for wood.
During his conversation with the rep, the subject turned to concrete. Kevin noticed that Duckback also produces a concrete stain. Having a gray patio of his own, his interest was piqued. The company says this stain is water soluble, easy to use, and cleans up with soap and water. The stain comes in 10 colors, including terra cotta.
Although safe, we suggest that normal precautions be taken at all stages when applying the product. Wear long pants, sturdy shoes, a long-sleeve shirt, gloves, a mask or respirator, and eye protection.
Application is a three-step process: Etch (roughen) the concrete with an etching solution; clean and neutralize the etching solution and allow the concrete to dry; then apply the stain.
For more information and to find retailers carrying these products go to www.superdeck.com.
Painting the cinder-block wall requires a different procedure. First loosen the vines from the wall and lay them on the ground. No need to cut them. Next, pressure-wash the wall to remove dirt and plant debris, and to provide a clean surface for the paint.
Once the wall is dry (give it a day or two in warm weather), apply a heavy coat of block coating. Block coating has the thickness of marshmallow creme and effectively fills in the voids and reduces the porosity of the concrete block.
It’s possible that retailers know this material by another name. Just describe what you intend to do and they should be able to supply you with the right product.
Finally, paint the wall with a good-quality latex paint. One coat might do it, but more likely it will take two.
Give the paint three or four days to dry, then replace the vines on the wall. When you’re done, you’ll have a colorful and clean-looking yard.