Moldy Wood Door--Paint or Replace

I purchased a wood front door with glass inserts for an apartment in coastal San Diego in 2003. The front patio area in the four years after I purchased the door had a problem with water ponding or pooling during heavy rains. As a result, it took a long time for things to dry out and the the lower part of the door received heavy mold stains. That problem has now been resolved. I sanded and oiled the door with Watco oil in 2009 and 2010, but it didn't entirely remove the mold stains. Do wood doors take well to paint and would I have to remove the door to paint it? It was extremely difficult to install the door because the door frame was at an incline. If it's better to replace the door, is there a such thing as mold or weather proof doors for a high salt (coastal) environment?

You might consider a fiberglass entry door. If the moisture content of the door is under control, a good primer designed for blocking stains, then a good exterior paint should work on the existing door. You really want to get a good coat of pain on all sides, especially the bottom, so taking it off the hinges would be the easiest way to get a good job done.

Another possibility is to prime the door with a product called Kilz. This is a primer/sealer and should seal and prevent the stain from coming through. Kilz is available at any paint store. I concur that removing the door off the hinges would be the best way to apply paint.

A door should never be wet. You should fix that problem. If water gets near the bottom of the door, the door will suck it up like a sponge, usually ruining the door completely. Make sure to seal the BOTTOM edge.

If the wood is not actually damaged, you might need to paint it. It will be hard to get rid of the discoloration caused by the mold. If there is any active mold growth, treat with moldex. Because you have oiled it a lot, you will need to paint with a solvent based primer, like kilz original or BIN 123.