Preprimed trim - did I do something wrong?

[Tim Shoppa]

I put preprimed exterior casing around several of my windows and doors several years ago. I topped it off with oil-based exterior paint.

At the same time, I put some new trim wood (not casing) on the outside, used an oil-based primer, and an oil-based topcoat.

Now, 5 or 7 years later, the wood that wasn't preprimed is in fine condition. But in some cases the casing that was preprimed is starting to peel. And it's not the topcoat peeling off the primer.

Did I do something wrong 5 or 7 years ago by using oil-based paint over the preprimed casing?

Or is it just that 5 or 7 years later it's time to re-prepare (scraping and sanding as necessary) and re-paint anyway?

Tim.

[Joe]

No, the factory applied primer was some very cheap stuff.

That is true in cases where the finish takes a lot of abuse from sun and weather. Average conditions may see a paint job last a dozen years. YMMV, of course. Check Consumer Reports for articles over the years on paints and testing...hughly informative.

Joe

[Steve]

Tim Shoppa wrote on 21 Jun 2007 in group alt.home.repair:

I remember asking a professional painter once about the difference between low-end and high-end paint. He said that with low-end paint, you'll need to repaint in about five to seven years. With high-end paint, you'll need to repaint in about five to seven years.

[Tim Shoppa]

Could be. I remember worrying 5 or 7 years ago that maybe I wasn't supposed to put oil-based topcoats over the maybe-latex primer from the factory.

The places where it's peeling are where *both* there's some fine detail in the casing AND where there's abuse from sun and weather.

What's sad is that I used the pre-primed casing especially where there was lots of abuse from sun and weather, with some thought that it would be better than what I could do in terms of putting primer over bare wood. Maybe I was just naive.

Tim.

[Tim Shoppa]

:-) Maybe!

7 years ago what I was doing was replacing wood with water and termite damage.

What I'm doing this summer is more general (but of course where it gets wetter or more sun I have to spend more effort preparing).

I think I can tell the difference between cheap and expensive paint when I'm applying it myself. The expensive stuff generally seems to spread and flow better. But 7 years later, it might indeed be hard to tell!

And I can't hardly buy oil-based topcoat paint anymore. I'm not going to say it's impossible but I cannot buy more than a quart at a time due to legal restrictions. I don't know if these restrictions exist everywhere or just where I am (Maryland). The good latex stuff today seems better than the latex of 20 years ago, I know.

Tim.

[dpb]

How are we supposed to know??? :)

Maybe, maybe not. I'm sure there was information available from the manufacturer on whether the primer was compatible w/ latex, oil, or both, but I surely can't tell from here and now...

In general, it was most likely a dual-use primer but my experience has been that the prime coat on most of that is _very_ thin and doesn't hold up any better than unprimed prep'ed well and primed on site.

If it needs repainting, it needs repainting...not much more can be said.

--

[Steve]

Tim Shoppa wrote on 21 Jun 2007 in group alt.home.repair:

Kidding aside, high-end paint DOES have some advantages, like spreadability. I use a lot of different paints, because my clients usually want to buy it themselves or match an old can. I just haven't formed a clear opinion whether the advantages are worth the extra cost. Maybe it's my technique, but I can't seem to get brushmark-free finishes with ANY kind of paint, even using Floetrol.

I'm in Texas, and there are no limits on purchase quantities of oil- based paints, but the last gallon I bought to do crown moulding poured out of the can in one big glob. I had to thin it to death before it would go on smoothly. The EPA has made the manufactures take the VOCs (Volatile Organic Compounds / thinner) out to improve air quality, so now the user has to put them back in, thus breaking even on air quality. On the plus side, I got two gallons of paint in a one-gallon can.

[J.A. Michel]

They often use cheap, sub-standard primer. Your paint is as only good as the primer. I had the same thing happen on some new exterior doors I installed. They doors and frames came pre-primed. I painted over them, and they were peeling within a year. I had to scrape and re-do them.

[Kitep]

I'm getting ready to put up some preprimed trim myself. After reading this thread, I'm tempted to re-prime. Actually, since I have to prime the walls anyway, it'll probably be easier to reprime than not. :)

[ransley]

You dont know what was put on the pre primed wood, maybe it was interior latex. I would never use pre primed on exterior.