Exterior finish on pine doors

[Chris Brueckner]

I have two front doors that I’m in the process of stripping and sanding down. What a job! I’d like to re-stain the doors, but I’m looking for an alternative to the spar urethane that was applied before since it started flaking after about a year. After 4 years, I can no longer do simple touch-ups – so here I am. The doors are exposed to the sun (facing south-west) and rain (second story overhang & no storm door). I’ve heard of some people using linseed oil as a protective coating, but I hate to give up the gloss that I had when I first hung the doors. Any suggestions?

[Bruce Miller]

Hi Chris:

Unfortunately, I know of no clear finish that is tougher and more durable than gloss polyurethane. A tung or linseed oil will offer virtually no protection, particularly the latter. The oil will not peel, as it is not a coating but a penetrating finish….but the wood will rapidly deteriorate.

The real trick here, and the most likely cause of the previous peeling of the ‘spar urethane’ is poor surface preparation or poor preparation between coats. In that harsh environment, your door must be sanded back to clear wood, and the wood must be scrubbed of all impurities, using something like TSP, and then rinsed and rerinsed. Then out of direct sunlite and between the temperatures of 60 and 80 degrees F, apply a Flecto or Verathane gloss exterior urethane. Let dry and sand using 220 grit, then recoat, dry and sand using 320 grit or 3-0 steel wool, then a final light coat. Make sure to seal the underside and top of the door in the same way. Might want to consider adding a storm door with low ‘e’ glass to keep the damaging ultraviolet rays off the finish.

Perhaps others here have another method they like to use. But this way has worked for me on several occasions, and should give you several seasons of a good looking door.

Best wishes

Bruce M

[Author]

Posts