If you get the urge to paint, keep an eye on the weather forecast. Painting exteriors in the autumn can be done but you need to be careful.
Exterior products need to cure a little before being subjected to cold temperatures and moisture. Latex paint that feels dry to the touch can re-wet when dew settles on it causing it to streak or bleed out surfactants, a brown soapy substance that is in paint to keep it from foaming in the can. It’s best if the night time lows are above fifty degrees but 35 degrees and dry will not hurt most paints.
If you have to paint, remember to paint early. You can start applying paint as soon as the surface is dry and the temperature is above thirty-five degrees. All of California Paints and all of PPG Paint’s exterior latex paints can be applied if the temperature is above thirty-five degrees. California Paints has added a line to specifically address this weather, Malibu. Malibu develops an early moisture resistance that allows you to paint longer with less worry about impending rain or dew. With most paints you should stop three to four hours before sunset so that the paint has several hours of curing in the warm weather before the dew hits it. This doesn’t eliminate the possibility of re-wetting but we’ve found that, in most cases, the added drying time increases your chances of a good paint job in less than desirable conditions. With Malibu you should still allow 2 hours before rain or dew.
Standard painting practice is to never paint if rain is forecast in the next twenty-four hours and make sure that the surface is dry that you’re painting. Remember that bare wood absorbs a lot of moisture and you should let it dry several days before priming so that you’re not trapping moisture under the paint. Trapped moisture is a main contributor to peeling paint.
So, let’s review. Paint early, stop early and watch the weather. Nobody likes painting enough to want to do the job twice.
With summer weather there are some special precautions to take. It is a common belief that paint that dries faster is better. This is not the case. Paint that dries too fast does not adhere as well, The best painting temperature is below 85°. When the temperature gets above 85° the paint dries too fast and does not have time to stick to the substrate.
So, a few simple rules:
- Paint Early. Start painting as soon as the surface is dry.
- Stop painting as soon as the temperature starts flirting with 85°. I’ve heard it said that if it’s too warm for you it’s too warm for the paint. You should embrace this rule and use it as an excuse to get a cool drink, sit down and watch a baseball game. If the person who wants the job done complains refer them to this blog and say there’s nothing you can do about the weather.
- Start on the south side of the house and let the sun chase you around the house. South side to west side to north side to the east side. This way the only time you are painting a sunny side is in the morning before the surface has had a chance to get too warm. The surface temperature of a wall in direct sun on an 80° day can reach 120°. I once went out to a job where a guy was painting a south wall in the middle of a 90° day and watched the paint start peeling before he had finished painting the wall. I never could convince the guy that it wasn’t a paint failure.
A few other things to remember. You should wash your house before you start painting and you should give it some time to dry. This is extremely important if you have bare wood. I like to recommend a week before priming the bare wood but if the temperatures are warm and humidity is down you can cut that to three days if your priming with Seal Grip Latex Primer. If you are priming with an alkyd primer you should err on the conservative side and give it some extra time.
Remember, your successful paint job is our best advertisement. When you’re done with your house we don’t want to see you again for exterior paint for a decade or more. We do want to see your friends and neighbors after you tell them about Salem Paint Company and the quality products and advise that you received here.