Staining the vertical trim around windows and doors can prevent a number of challenges. Luckily, there are a few simple steps to end up with great-looking results.
The first challenge when staining windows (and sometimes doors) is the glass. Glass can actually absorb stain, so it’s a good idea to apply strips of painter’s tape before you begin. And be sure to remove the tape right after completing the project to avoid disturbing the finish.
Also, carefully remove, label, and store locks, latches, and pulls to decrease the possibility of leaving runs and drips.

Conditioner — Many woods absorb stain unevenly, leaving blotches. To prevent this, first sand and remove the dust, and then apply a liberal coat of pre-stain wood conditioner with a foam brush (Photo, above).
Gel Stain — Let the conditioner sit for 10 to 15 minutes, and then — before it dries — apply a coat of stain. I recommend a gel stain for windows. It’s a thick, heavy-bodied stain that is less likely to run or drip than liquid stain. The use of pre-stain wood conditioner will lighten the stain color, so test the conditioner/stain combination on a scrap piece to make sure it’s what you want before applying it to the windows.
Apply the gel stain with a foam brush, working from the top down (Fig. 1). Let the stain absorb for one to ten minutes, depending on the darkness you desire. Then wipe the surface with a clean rag.
Fast-Drying Poly — The stain should dry in eight hours, after which you can apply finish. For protection, durability, and easy application, I suggest fast-drying polyurethane. Apply it in thin, even coats with a natural-bristle brush, and shine a worklight on the wood to detect runs before they dry (Fig. 2). Twenty minutes after each coat, open and close the sash to ensure the finish doesn’t bond the window shut.
Spar Varnish — The windowsill takes a lot of abuse from water and sunlight. For that reason, use spar varnish to finish it. This type of finish has UV inhibitors to make it more resistant to peeling and fading (Fig. 3). When it dries, the varnish matches so well that no one will realize you used two different finishes to protect your windows.
Have a nice weekend,
Wyatt Myers
Online Editor
Workbench Magazine
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