Our house paint is peeling off, but only is spots directly hit by the Long Beach sunlight. I can't tell if it's from moisture under the siding--I have shake. I'm sure we need to strip, sand, and doing the painting over. What can I use to patch the surface before priming?
Walter J. ~ Long Beach, California
Hi Walter, Exterior paint peeling in direct sunlight is usually a pretty good sign that there may be a moisture problem as you suspect. The difficult part is going to be discovering the source of the moisture, it could be coming from the interior of your home or it could be coming from the roof or your shake siding.
I would not be in a rush to start repainting until you have solved the moisture issue as the paint peeling may just start again after a while. You didn't mention how long ago your home was painted. If it wasn't that long ago, the problem could be simply that the siding wasn't completely dry when the paint went on. I imagine that Long Beach, California can be fairly humid at times, I'm not sure how often it might rain there, but if the shakes weren't completely dry, then the exterior paint doesn't adhere as it is designed to and peeling can occur.
If it has been several years since the home was painted, then that probably isn't the problem. The first place I would look is the interior of your home as that is the easiest to rule out. If there is a kitchen or bath with water lines on the exterior wall, I would investigate them for leaking. If there are no kitchen or baths located in that area, then start looking outside.
The moisture could be getting behind the siding from a missing roof shingle, a crack in one of your siding shakes, or something as simple as some caulking coming loose. Finding a water leak is a trial and error ordeal that can take several attempts before you locate where the moisture is intruding. Using a water hose with a light spray can sometimes help find the problem spot.
Any shakes that are split or cracked all the way through, or close to it, should be replaced rather than patched or you may be looking for another leak in the near future. Gouges and small holes can be patched with an exterior wood filler or spackling compound and then sanded smooth before repainting. I would also pull out all old caulking and install new prior to repainting your siding.
As I mentioned above, make sure the siding is completely dry before you put your prime coat on, and that it has a chance to dry before any rain hits it. I would also invest in a good quality exterior primer and paint as in my opinion it can make a big difference in the life of the paint job.