Painting Pressure Treated Wood

[KahrMan]

Put up new front porch railings about two months ago.  I have heard that you have to let pressure treated wood sit for a while before you paint it or the paint will not last long.  Any tips on how to prep the wood, what paint to use, etc. would be helpful.

 

Thanks

[Spots]

You need to let it sit for a year. Lightly sand it and clean it well before painting. Rinse it with a hose and brush it clean, dont pressure wash it. This advice comes from my father in law, a 35 year general contractor.

Tapatalk ate my spelling.

[2.ooohhh]

I usually wait a full summer.(build in early spring, paint right before winter) Only way I've found to reliably speed up the process is to dry the lumber in an air conditioned environment for several weeks with good ventilation, then sand and finish. (likely not an option on your railings at this point)

[peejman]

What they said.  Wait until next summer.  Need a dry stretch of about a week, couple days before painting and a couple after. 

 

Any of the standard exterior grade paints should work fine.  It looks best if you brush it on, but that's pretty tedious if it's a big job.  If you use a sprayer, thin the paint and do several coats, and mask everything around it (which will likely take longer than painting). 

[Guest Lester Weevils]

I use Flood clear stain rather than paint. I've had a painted porch and every time its time to paint around all those rails and details, scraping takes many multiples of the time and aggravation than does the actual painting.

 

Some opaque stains have to be scraped and chipped just like paint. If you get a bunch of algae on clear stain, it is some annoyance cleaning it off for another coat of stain, but nowhere near the annoyance of chipping paint. I've usually used "high quality" polyurethane porch paint on my painted porch, white and gray. Maybe some other kind of paint would be better, but no matter how solid the paint looks right after careful surface prep and application, it is ugly and peeling after a couple or three years and you have to keep doing it over and over again.

 

So if ya gotta keep doing it over and over again regardless, seems most sensible to use something that minimizes surface prep before re-coating.

 

(Am no expert, just personal experience, and maybe my paint sucks and I was holding the brush wrong.) :)

 

Edit note-- Clear stain comes in many colors. The clear is merely a kind that allows the grain to show thru.

Edited July 24, 2013 by Lester Weevils

[KahrMan]

Thanks for the replies.  Guess I will be waiting a little longer before I paint.

[Guest Bonedaddy]

You need to let it sit a good year before you paint so that the chemicals in the wood completely dry and neutralize. If you are going to "paint", you need to prime, at the very least, with a good "bonding" type water borne primer but I much prefer to use an oil based enamel undercoat because oil base penetrates "into" the substrate, whereas, latex tends to just sit on top with a tight grip, though hard to breach when cured. But over time, moisture will breach it and make it lift. Hence the bubbles you see on many old latex painted things outdoors that require scraping. It can happen with the oil, too but happens much less with an oil based primer from my own experience (30 years). You can top coat it with any good exterior paint but use, at least, a satin, if not semi gloss finish to reduce absorption of moisture. 1-2 primer coats and at least 2 finish coats. If I spray, I'll use a .209 tip with an airless and just enough pressure to keep it from trailing, so as to reduce overspray because there are a lot of small places to paint on a deck and you don't wanna waste that much paint. May take a tad longer but it's worth it. I prefer a 2 gal. pressure pot, running 40-50 lbs. of pressure off a strong compressor because I can play with fluid amount, pressure and fan width to fit any situation. Just thin the paint accordingly but as little as you can get away with. It wouldn't hurt if the wood was sealed first with something like Thompson's water sealer to stop moisture soak from underneath the deck, too. If you use a urethane or polyurethane paint, read the can for priming instructions. Many don't take a primer but itself. They can be real picky about what chemicals lie underneath them, just as those found in many basic sanding sealers. When you see interior stained wood doors that have those little white looking blister spots where they'be been bumped or scratched, that was what caused it. Some painter used the wrong sanding sealer underneath polyurethane when he should of just used the poly to prime the door with and sand that. Well, there's a start for ya, anyway.