ask This Old House
• Tips, tricks, and answers to your home-improvement questions
Painting exterior wood railings
I have cedar front-porch railings that I built years ago. The paint is gone in many areas or is peeling away. What is the best way to prep weathered cedar and repaint it white?
—BRAD STUBBS, LEE’S SUMMIT, MO
TOH painter Mauro Henrique:
Cedar resists rot and insect damage, so it will be worth your while to get your railing back into shape. Paint is a good choice for your railings; it will hold up to sun and weather exposure better than other types of exterior coatings.
To start, lay down a drop cloth to collect paint scrapings and protect the porch and stairs from paint drips. Then use a paint scraper to remove all the loose and peeling paint. Next, go over the railing with an orbital sander and 180-grit sandpaper. The parts of the railing you can’t reach with the sander can be sanded by hand, using 120- or 180-grit sandpaper. For any paint still bonded to the wood after scraping, feather the edges of painted areas, so they’re even with bare wood surfaces. When you’re done sanding, suck up all the dust with a shop vacuum, and mask off the base of the posts and any balusters that rest on the stair treads (see Tip).
The next step is to apply an oil-based exterior primer. I like to use a miniroller to quickly coat the wood, followed by a 2½-inch brush to smooth out the roller’s). Apply it with a flexible putty knife and scrape off the excess. When the filler is dry, give it a light sanding with 180-grit sandpaper, taking care not to sand through the primer coat; just smooth the filler and make it flush with the surface. Wipe away the dust with a tack cloth or a rag dampened in denatured alcohol.
