Ask The Expert
I built a small changing room in our back yard. The wife wanted a cabana room. I did everything including the exterior stucco finish (my first time) which we painted blue. Now there are white patches on walls, like the paint is fading very fast, and it is cracking. Is this because of the proximity to the pool and moisture? Is there a sealer that is supposed to be used? Thank you,
That’s called alkali burn. When you first mix stucco and Portland cement, they have a very high alkalinity; we say they’re “hot.” The alkalinity remains high until it cures, which takes about 28 days. This is why you always want to wait one month before painting stucco or cement.
Stucco is safe to paint once the pH gets to about 9.5 or lower. On the pH scale, 7 is neutral. Below 7 is acidic and above 7 is alkaline. There are several different pH testers on the market. You see a lot of the pH pencils and a pH liquid that you splash on the surface. The color will then determine what the pH number is.
Some of your larger paint companies will come out and test the surface for you, depending on the size of the job.
The cracking is caused by what they call saponification. This is when an oil based paint is applied on a masonry surface that is not cured. It’s a chemical reaction that occurs between the oil based paint and the hot surface where it is being applied.
Another problem that usually occurs is poor adhesion. Your paint will probably start peeling off as well.
To repair, you’re going to have to remove all of the paint. It can be scraped or jetted off. Make the repairs to your stucco as needed. Let cure completely. Test with a pH kit, use an alkali resistant stucco primer and repaint.
I pulled into a condominium parking garage and out ran a homeless person. I spoke with her briefly and she said she had been trapped in there for a few hours. I don’t like the idea of somebody having access to the vehicles, but isn’t it illegal to not provide an exit out of a garage? I know all of the tenants have clickers, but what about non-residents? Thank you,
You are absolutely right. They are violating a building code by not having at least one pedestrian exit. You cannot entrap a person in any structure. There should be a door with a panic bar – a horizontal bar you push to open, where everybody, resident key holder or not, can exit the building.
Every building must have exits points available through panic hardware, which must be clearly identified as an exit, or via a guard or attendant.
Not every pedestrian exit is required to have panic hardware, but they must be made available – unobstructed, in good working order, and lead to the outside.
Submit questions to: firstname.lastname@example.org. Robert Lamoureux of IMS Construction, Valencia, CA, has 30 years experience as commercial General, Electrical and Plumbing contractor. The opinions expressed in “Ask the Expert” are not to replace the recommendations of a qualified contractor after a thorough visual inspection has been made.