The experts at the USDA Forest Products Laboratory in Madison, Wisconsin advise that wood treated with waterborne chemicals, such as copper, chromium, and arsenic salts (CCA) can be painted right after installation before any weathering occurs (assuming the wood is dry). Wood treated with solvent or oilborne preservative chemicals, such as pentachlorophenol, is not considered paintable until all the solvents have evaporated

donb1959 said:

In a couple days I will be painting a newly constructed sunroom. There's quite a bit of treated lumber in this project. I have never in my 15 years painted new treated lumber. She is insistant that we proceed even though I have always heard that treated lumber needs to "age". Any special precautions I can use with this. Im thinking prime it with oil based primer...but I need a little input, thanks.

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Thanks GPI, I appreciate that. OK guys I'm starting this project in 3 days, Ive heard everything from DONT DO IT!, to "You'll be fine so long as you use a water based primer/finish", to "Yup, it'll work, just need to use all oil based stuff".This lady has spent 15K on a damned sunroom, she wants the treated lumber painted, the sunroom has been built for two weeks. I, on the other hand really hate to paint this lumber and have it come off in sheets in a month.

I KNOW some of you guys here have painted freshly constructed treated lumber, so, leave your pantys at the door, and give me a suggestion

If not I make have to suggest that Nate make a "all skeered to give advice on painting treated lumber" forum with the new Contractor Talk format, dont make me want you fellas :evil:

Since you are looking for input. I am not a painter but a deck builder so I do know treated lumber. My advice is to NOT do it. Treated lumber is soaked in the solution and pressurized. It arrives at the lumber yard dripping wet. So unless you got some stock that had been sitting around for a year, it is going to take a while to dry out.
If you must do it, I would get the customer to sign a waiver that you will not guarantee the paint to stick. Good luck.

I might be skeered, but I will chime in with this:
I agree with the dude above me. It should weather/dry out before painting.
If I was to paint it, I would use a 100% acrylic primer, only for the fact that it will allow it to breathe (dry) a sight better than oil would. An a cheaper vinyl latex is what will pull off in sheets. And think twice about top coating it with a heavily-enameled product, like a semi-gloss, or those new water-borne trim paints. Too thick and vapor barrier-like to make me feel good about this application.

So there you go, all my 2¢.

BTW, get that disclaimer signed too. CYA

My input comes from a total neophyte, I do not paint for a living, and I have not a CLUE what the correct answer is. Therefore do not put stock in my little story.

Having said that back in March I cut some brown pressure treated 4x4 (that I probably bought on February 6th) for a foundation for a shed.

I primered it with Zisner on March 15th
I put a coat of high gloss white on it March 16th
I put a second coat of gloss white on the timbers on March 25th
On June 1st I joined the timbers to the pier blocks
I erected the shed on top of this during the last 2-3 weeks. At that time I put another coat over what I already had on the visible side to touch up some construction-related scuffing and other imperfections.

So far.... and I do want to stress SO FAR, I have not had any problems at all. I have drilled the stuff, screwed and nailed into it, walked on it, run a wheelborrow over it a few times, and sprayed it with a high pressure nozzle on a garden hose, had it bake in 100+ degree weather and had it rained on - so far with no ill effects.

It may all peel off next week, but so far... no problems.

This is neither advice nor suggestion, just a report of what I have done. Continue seeking advice from real experts.

Ok guys...thanks.

And think twice about top coating it with a heavily-enameled product, like a semi-gloss, or those new water-borne trim paints. Too thick and vapor barrier-like to make me feel good about this application.

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So, Pro, I should prime it with a high quality acrylic primer, but then what to top coat with? If not enamel, and not water borne, what?

Don,
Can you use a solid stain instead of paint? I have stained decks right away and have only seen issues with the floor sections because of traffic. Maybe you could talk the customer into a stain and then paint next year.

Everybody knows or should know that you don't paint PT for a year. The exception is a solid stain or Penofin for PT.

If the customer insists get a disclaimer/hold harmless signed by her and paint away. It's her money, just make the wording as scary and one sided as you can because chances are good she will be pissed at you no matter what she signs.

Since I was skeered, I didn't really think past the primer stage.
Can I change my vote to the stain also?

donb1959 said:

Ok guys...thanks. So, Pro, I should prime it with a high quality acrylic primer, but then what to top coat with? If not enamel, and not water borne, what?

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Not to get anyones girdle in an uproar, but not all treated lumber is pressure treated, and not all are treated in the same way or same products, so yes it does make a diff. what its treated with and how it was treated to know if it can be primed and painted now or later. As my orig. post states. Seems as if the focus was lost somewhere between I have done it and have heard it cant be done. Again, research your product and you will know. Damn chemists.....lol

ProWallGuy said:

Since I was skeered, I didn't really think past the primer stage.
Can I change my vote to the stain also?

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Man, everything I see around here is ACQ.

GPI said:

Not to get anyones girdle in an uproar, but not all treated lumber is pressure treated, and not all are treated in the same way or same products, so yes it does make a diff. what its treated with and how it was treated to know if it can be primed and painted now or later. As my orig. post states. Seems as if the focus was lost somewhere between I have done it and have heard it cant be done. Again, research your product and you will know. Damn chemists.....lol

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Guys, I use a high grade latex primer (Benjamin Moore or Gripper) but the copper will bleed through (blue). If using a bright white for top-coat, you will more than likely need two coats of a premium latex to make sure you cover the copper bleed. That is my experience for the last year. I've had different reps tell me to use an oil-based primer but I like to use latex whenever I can on exteriors unless I'm blocking stains or sealing alligatoring.

I like solid stains but I have not used any on newly installed pressure treated wood. I would bet that the copper bleed will occur. If I'm using stains on deck boards with traffic, I'll prime the boards with an oil-based primer 1st then use the solid stain on top. You won't get peeling. Sounds funny but i got it from Ben Moore direct and it has worked great for three years. Either way, I think the old belief of waiting until the new wood has aged is wrong. Once the wood has aged, some damage to the wood has already occured. My opinion.

Mike Finley said:

Man, everything I see around here is ACQ.

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The problem comes from sealing moisture in wood. Ever seen the whole side of a house peeling down to bare wood, or bubbles in the paint? It's the moisture trying to escape. A lot of wood siding is installed without back-priming which prevents moisture from getting in the back side of the wood. Moisture enters the back, then lifts the paint as it tries to escape the front side.

With treated wood, all of the moisture is still in the wood when you buy it. You may get lucky for a while, or even dodge the issue with stains...but latex coats will peel BAD eventually...oil too. Painting is not opinion it's science.

BTW, the wood is treated to prevent damage. It will age fine for a year. The only damage will be weathering on it's surface.

Ratrub said:

Guys, I use a high grade latex primer (Benjamin Moore or Gripper) but the copper will bleed through (blue). If using a bright white for top-coat, you will more than likely need two coats of a premium latex to make sure you cover the copper bleed. That is my experience for the last year. I've had different reps tell me to use an oil-based primer but I like to use latex whenever I can on exteriors unless I'm blocking stains or sealing alligatoring.

I like solid stains but I have not used any on newly installed pressure treated wood. I would bet that the copper bleed will occur. If I'm using stains on deck boards with traffic, I'll prime the boards with an oil-based primer 1st then use the solid stain on top. You won't get peeling. Sounds funny but i got it from Ben Moore direct and it has worked great for three years. Either way, I think the old belief of waiting until the new wood has aged is wrong. Once the wood has aged, some damage to the wood has already occured. My opinion.

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Don't let the owner tell you what to do...only to blame you later when the coating fails. Why not check the moisture with a meter? I'd bet that on the new ACQ you'll get readings all over the ballpark. If its too wet to paint or stain..don't do it unless you want to waste time on a callback.

Good call Dale.

Why not check the moisture with a meter?

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research your product and you will know. Damn chemists.....lol

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How does one go about finding out what and how it was treated with?

Can you all see why I don't paint exteriors?

The company that built the sunroom (ArchaDeck) has assured the homeowner that this treated lumber used can be painted immeadiatly, so I wrote a cool disclaimer, and started painting, I'll let ya know how it turns out.

Hey Don, how 'bout posting a copy of that there disclaimer?

.....yeah...and I'd like to know what kind of pressure treated lumber that is. Its all ACQ here and that stuff is practically dripping.

I won't touch PT for 2 months min. even if the marketing dept...um...manufacturer says I can paint right away

We have both kinds in this area, and they are not clear about which is which
Nor do I trust the H/Os on what they think they have
I figure better safe than sorry

I also mostly use an oil-based solid color stain if they want it "painted"
This area is tough on decks and latex is not durable enough for me

I'm sure I have lost work because of the (perhaps un-needed) wait
I wouldn't mind trying it sooner-I just don't want it to be on my dime
I wouldn't do it on my deck

I think the disclaimer is a great idea
I'd think a lot of H/Os would decide to wait when confronted by a disclaimer, but if they don't want to wait I wouldn't mind going ahead as long as I had a disclaimer
I'll keep that in mind if it comes up this season

I'd also like to know how that sunroom turns out