I need advice on painting newly installed cedar siding. Last fall my contractor installed 6 inch cedar lap siding. The siding is vg cedar with a factory prime coat (oil based – all six sides) and a finish coat (acrylic) on the exposed side. We used stainless steel nails. The trim is finger jointed pine, also factory primed on all six sides, with one finish coat (acrylic). My intent is to wash it all with a mild solution of TSP, then paint the second finish coat.
If I set the nails, and fill, what is the best filler to use and do I need to prime before I fill, and do I need to prime after I fill. If I need to prime, will a latex based primer be better than oil based. It seems to me that putting an oil based primer over the acrylic finish coat is not a good idea. (In either case, I plan on a touch up of one finish coat over the filled areas before I put on the second coat.) In the past I have used 2 part epoxy filler (Abatron), but it is a pain. Would Elmer’s int/ext wood filler (orange, blue and white tub) do the job?
If I don’t set the nails, I will insure they are flush. Do I need to prime them? If so, is a latex based primer okay. Again, I am not sure about using an oil based primer over the acrylic first coat.
Any advice will be appreciated. Thanks.
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Bumped for a reply.
I've had the privilege of being a painting contractor in San Francisco for 31 years and the key with cedar is to contain the tannin acids at all cost. So to play it safe, we always prime after we set the nails with an oil-based primer, fill with bondo, sand and re-prime. Then apply the 100% acrylic finish coat. If you hammer the nails flush with the siding, make sure that you prime over the nailheads with an oil-based primer to re-seal any wood fibers that may have been exposed. Hope this helps.
Ok, I'll take a swipe at it. I would set the nails, fill with a bit of autobody filler being careful not to apply too much, sand lightly, no primer.
Another option would be this stuff:
http://www.eclecticproducts.com/solventbased.htm
...which says outdoor use is OK. I've only used it indoors. It's very easy to work with.
I'd try using Ready Patch on it since its newly applied cedar and I would recommend at least spot priming any place you add filler after sanding. Is the cedar still shrinking? You may see the primer coat just below the lap if it shrinks any further. Latex primer should me fine. Oil is more durable but not necessary.
I think I misread your post. I would not recommend sinking those nails into the cedar if they are not already. When hanging cedar shingles or siding, the nails are not supposed to be embedded below the surface.
I actually like the look of nails on lap siding -- gives things an authentic look. And setting the nails destroys the integrity of the surface, even if you do follow with a filler. Seems silly to install real cedar, bash the hell out of it, then fill the holes with synthetic filler. On trim use casing nails, and just set them flush.
My preference is for an alkyd primer exclusively for exterior work -- Moorewhite is my favorite. I'd prime everything that isn't already primed -- cut ends, nails, caulk, etc.
Set nails - no need to prime before filling. I like MH Ready Patch (it does shrink and needs 2 coats) or Elmer's Carpenters. Prime filler before painting - I like Cabot Problem Solver Primer. Tint primer to be close to finish color.
I installed cedar shingles on my own home. I did not set the nails below the surface. I just nailed them flush, but some did tend to set a little below the surface just because of how soft the cedar is. The shake nails I used were galvanized (but of course, SS is better) and the heads aren't even visible unless you stand next to the siding and actually look for them.
I think that filling and sanding could easily create a texture change in the surface that would be MORE noticeable than the small nail heads.
Regardless what you do with the nails, I would prime the nail heads and anything else that was disturbed with a tannin blocking oil-based exterior primer. You may want to tint the primer close the the final color otherwise you may need 2 more topcoats to to get an even color.