Replies

1. 
   DanH | Feb 24, 2011 07:43am | #1

   The guy who built our house didn't prime anything.  Most of the window/door trim was "factory primed", but that was it.  When it came time to reside about 20 years ago, we ended up scraping off probably 90% of the paint down to the bare wood (including the "pre-primed" areas) and repriming (with BM Moorewhite alkyd).  Since then, the only peeling that has occurred has been on that 10% we didn't scrape and prime.

   Of course, in your case it may be that the existing paint is suffiiciently well-adhered that it doesn't need to be scraped off, so the question is whether the new paint will adhere well to the old.  But probably you'll end up scraping about 25% of that 5%, after which it will need priming anyway, so might as well do it all.

2. 
   Hokuto | Feb 24, 2011 10:10am | #2

   Thanks to Mark and Dan for the confirmation; I had come to the conclusion that priming was the best bet, and that's what I'll do.

3. 
   RichardH | Feb 24, 2011 11:32am | #3

   I *always* primer over old paint, inside or out (unless it is the odd 'quick & dirty' job that I rarely touch).

   For exterior work make sure the primer is designated for exterior use.

   I too often have to work with paint that was applied over improperly prepped material--not sanded, not primed.  Although I use Sherwin-Williams paints for just about everything, I more and more use Zinsser 123 as my primer of choice.  It hides all kinds of sins and leaves a nice smooth finish.  It also is ready to recoat in an hour (unless you are using it to seal.)  The only thing I don't like about it is that it does set up very quickly and is a little difficult to clean up.

1. 
   Hokuto | Feb 24, 2011 06:49pm | #4

   Thanks, Richard, that helps. The primer I'm using is Benjamin Moore's Fresh Start 100% Acrylic All-Purpose Primer, which is supposed to be good for interior or exterior.