Replies

1. 
   PlaneWood | Jun 07, 2004 08:03pm | #1

   I would wait a while.  Maybe a month.  Priming with KilZ wouldn't hurt.  Are you going to use Oil or Latex based paint?  Latex might be my choice.  Don't get a cheap brand though.  Behr (available at Home Depot) has been pretty good for me.  Are you in high humidity or low humidity country?

   PlaneWood by Mike_in_Katy (maker of fine sawdust!)
   PlaneWood

1. 
   toddhunter | Jun 07, 2004 08:25pm | #2

   I'm in Chicago, plenty of humidity. The wood is very wet now. I assume the moisture is compatible with oil or latex? I'm just looking for the most longevity and ease of re-application. Todd

2. 
   UncleDunc | Jun 07, 2004 09:53pm | #3

   This subject comes up regularly at Breaktime. Go over there and use the Advanced Search button to search for messages containing all the words

   pressure treated paint

   and you'll get advice from guys who have done it. I could try to summarize for you, but I wasn't paying that close attention and would probably get it wrong.

3. 
   bobpowers | Jun 07, 2004 10:44pm | #4

   I replaced some lattice work on the front of our house a few years ago, using pressure-treated wood.  I finished it with an opaque exterior white stain.  With the exception that I should have used a stain sealer on the knots,  it looks good.

4. 
   Mackwood | Jun 08, 2004 02:21am | #5

   Definately use a latex primer.  That's what Sherwin Williams folks recommended when I asked the same question of them about two months ago.  I would let it dry out for at least 30 days before painting.  I would, however, prime the ends of the boards right away and again when priming the whole board.  Two coats of primer won't hurt anything either!  It will gain you longevity of the final finish.

   Regards,

   Mack

   "WISH IN ONE HAND, #### IN THE OTHER AND SEE WHICH FILLS UP FIRST"

5. 
   hammer1 | Jun 08, 2004 09:58am | #6

   I have painted PT with everything from oils to acrylics. The problem with it is the lumber, usually southern yellow pine. The rapid growth of this species means that the wood is very porous and it moves. Any coating will split and degrade. The best results I have had is to wait as long as possible for it to dry. Spot prime knots, filler and defects with white pigmented shellac or Kilz, prime entire surface with the best oil based primer thinned with Penetrol, top coat with acrylic solid color stain. After a few years, scrape, sand and repeat. Never thin top coats for primer, follow manufacturers recomendations. Acrylic primers are fine and almost as good as oil but don't expect any paint to last very long on that stuff. Cabot makes OVT solid stain. Their warranty requires their Problem Solver primer but they don't warranty the product on PT. Stop using that junk!

1. 
   toddhunter | Jun 08, 2004 06:51pm | #7

   Boy, there aren't too many topics that generate such widely varying opinions. Acrylic vs. oil. Stain vs. paint. Acrylic stain vs. oil stain. Deck stain vs. ordinary stain. Primer vs. thinned paint. Penetrating oil--or used as a thinner. Wait (a day, 1 month, 3, 6, 12) vs. right away vs. prime the ends now, then wait. This sounds like a perfect subject for a thorough study. Each argument has merits, at least in theory (see also Breaktime). Have I missed any? Thanks, Todd

1. 
   Mackwood | Jun 08, 2004 07:41pm | #8

   TH,

   I was told by the SW folks that the "oil" in oil based primers doesn't get along with the chemicals used in PT'ing.  ?!?!?!  I do have a sample of the oil based products not working.  We have a table with a PT ply. top outside our office that I painted with KM best ext. oil primer and top coated with two coats of oil based ext. semi-gloss.  It was painted about two years ago and it's failing at all the knots.  I don't know if latex would have worked any better but SW says it would have and they haven't steered me wrong (lately) LOL.

   Regards,

   Mack"WISH IN ONE HAND, #### IN THE OTHER AND SEE WHICH FILLS UP FIRST"

2. 
   OneofmanyBobs | Jun 08, 2004 07:47pm | #9

   Yep lots of opinions.  Experience rules, however.  I have yet to find an acrylic or latex primer that works as well for exterior as oil.  Not Kilz either.  Don't use thinned topcoat as primer.  Primer is formulated differently to bond better.  Penetrol is good stuff, but best used as a flow agent.  Makes it easier to brush.  I have not noticed any improvement in durabilty using it.  It reduces the effective percentage of pigment and filler.  How long to wait?  Until its dry.  Use a moisture meter it you have one.  Measure an old piece outdoors that you know is dry.  It has achieved equilibrium moisture content in your environment.  10 or 12 or whatever percent.  If you paint before it has dried to equilibrium, it will shrink and that makes it very hard for any coating to stay stuck.

2. 
   nikkiwood | Jun 09, 2004 08:37am | #10

   Re: Cabot products

   Hammer, in your post you mention Cabot OVT solid stains, and apparently, you've not had good luck with their line.

   My experience has been the exact opposite; in fact if Cabot has a product that will be appropriate for an application, that's the one I'll buy.

   But my main reason for replying here is to mention that I believe Cabot has a solid stain that is specifically formulated for pressure treated materials --- I recall it had PTW in the product description.

   I think Cabot really knows what they're doing, which is one reason they are so prescriptive in their directions. If they do have a product for PTW, I would certainly look into it -- way better than conventional paint.

1. 
   hammer1 | Jun 09, 2004 06:17pm | #11

   I think you misread my comment on Cabots. I think they make great products. It has been 2 yrs. since I used any, I don't usually paint my work. On the cans I currently have they state that they will not waranty their normal 12 yrs. on PT. They may have new products I am unaware of. That does not change the fact that PT is a difficult material to keep coated regardless of the product. I've built many decks over the years and repaired or replaced porches that were 100 yrs. old or more. There was no pressure treated lumber widely available back then and the rough hemlock that was often used has stood up as well as any PT. My own 22 yr. old deck was framed with ordinary spruce, posted with white pine and decked and railed in select PT. We do not have termites in my area. The frame and posts have weathered much better than the PT and held the solid stain well also. I copied my railing design from Monticello, the lovers knot pattern with many short small pieces. I collected pieces of PT from other jobs, stored until I had enough and milled and shaped the stock before installing. It was dry and clear to say the least. This did not make the stain last any longer. I would not recommend using spruce or pine for decking but I would not use PT either. Other than in ground contact, wet environments, or in termite areas I try not to use the stuff. Why would anyone want such an ugly product to last? You can't cover it up for long.