Stopping redwood bleed-through
I’ve been painting the redwood trim around the windows and doors in my office. Despite two coats of interior latex primer and two coats of exterior semigloss latex, I continue to get bleed-through from the redwood. What can I apply to prevent this?
John M. Schweifler, Lakeport, CA
Brian J. Doherty, a painting contractor in Richmond, Virginia, replies: The bleeding is because redwood contains high levels of tannic acid. Your problem is easily solved.
Your initial glitch was with paint choice: Latex primers and finishes are porous, which means that things like moisture, air and, in this case, tannic acid can pass right through. On the other hand, alkyd-based primers and finishes are not porous, and they contain and hide the bleed-through.
So on the work you’ve already done as well as on any remaining bare redwood, simply apply one or two coats of a highquality alkyd primer, such as Benjamin Moore’s alkyd-based Fresh-Start 024 (800-344-0400; www.benjaminmoore.com). Then just finish it with whatever you choose. Latex products adhere just fine to alkyd primers.