Finish for exterior wood door


Senior User
A friend of mine has a fairly new house, approx. 3 years old, that has a beautiful wood front door. They are having two issues with it.
First, the finish that is on it is not holding up to the sun at all, the bottom half of the door is really showing it's age.
The second thing, the wood is splitting, enough you can see daylight through it.
I do not know the door manufacture, she can get no reply from the contractor that built the house and they are about at wits end. I guess since she knows I do a little woodworking I'm an expert on how to salvage her door.
I'm assuming that since it is wood that it is simply going to expand and contract with the changes in weather. What would be the best finish to use that would stand up to the sun better? I did notice that the edges of the door did not have any finish on them, would doing so help with the expansion and contracting?
Thanks in advance for any advice you can share.


Corporate Member
FredP is spot on here. If you can see daylight through the splits, the likelihood is that the door is beyond any type of lasting, durable repair. The best finish for an exterior wood door, especially one exposed to direct sun, is Epiphanes in my opinion. This is a marine spar varnish that is the standard by which others are judged. Expensive? Yes. Time consuming to apply properly? Yes. Worth the time, money, and effort? Absolutely. All of the above applies to a natural wood door, with the intent is to preserve the appearance of the wood. Otherwise, high quality exterior latex paint is easily the most durable finish for exterior surfaces.

Hope this helps.



Senior User
Here is the outside of the door. If you zoom in on the bottom horizontal molding in the lower panel you can see where he put some putty to fill the gap. He said the gap was so small he couldn't get anything into the crack, that is why he smeared it so much.
It's a pretty door, it's a shame to waste it. door.jpg


Sounds like it was a thin solid door and not a well built insulated one with wood surfaces.
Anyway, might consider automotive 2K clear coat. UV protected, a bit flexible and very tough. Modern water based automotive paints have come a long way. Or, old school SPAR varnish stayed a bit soft and moved with the wood but on a boat, still was only good for a couple of years. Nothing beats keeping direct sun off it.

One could always salvage it a bit by adding a brass kick-plate across the bottom.

badger fan

For what it’s worth, I have a door that gets a lot of sunlight on it. After asking people on this site what to do regarding protection from sun and UV rays, I was directed to Sikkens as a finish. It has been very good the last 4 years. Highly recommend from experience.


There are two factors going on here, one is the finish and the other is the door construction. It's hard to say without seeing the splits but my initial guess is they are due to not accounting for wood movement in the door construction, not much you can do about that at this point. Finish on exterior wood doors are notorious for their short lifetime, expect only 3-5 years before they need to be redone. Fine Woodworking and Fine Homebuilding have articles on finishing exterior wood doors, some involve multi-step procedures using obscure products to help stave off the inevitable. Without getting that involved the general recommendation is marine spar varnish with UV protectants. UV is the main culprit for premature finish failure. An entry way porch/roof that shields the door from the elements will extend the life of the door and it's finish.


Corporate Member
My two cents worth;
I replaced my original front door, which was cheap, poorly made and also splitting and showing daylight thru it, with a door I made using African Mahogany. Your description of the door in question is, in my opinion and in agreement with many who have posted here, toast and should be replaced. I finished my door with General Finishes Exterior 450 finish, six coats sprayed and wiped down between coats with progressively finer Scotch Brite abrasive pads. It has a two foot overhang giving it some protection but also gets a lot of direct sun and weather. There is a full length storm door covering it. The finish I used has now held up beautifully for six years and is showing no signs of break down. The beauty of the finish is it is water based, dries in a couple of hours for either another coat or being able to be put back up so you have a door and not a giant hole in your wall. It is a LOT of work to replace an exterior door in an existing frame. Fitting, hinge mortise, door knob and dead bolt lock mounting, etc. Good luck.


Corporate Member
Here is another taker on the repair. This could be repaired. There are a couple of ways to do it. There is a epoxy the does not harden super hard and as such, has more flexibility. That could be a way to effect a repair. Another approach is to take the lower panel cove trim remove all the pieces and install a slight bigger one, then refinish.
Here is the economics of it. By the looks of this door it looks like a 5-7 hundred dollar door, the repair without the finish will get close to the purchase of a new door. Something I learned from building post offices -if the repair is about 35% of the cost for a new one, then consider replacement at that point ...unless there is a remarkable or extraordinary reason not to.

Phil S

Board of Directors, President
Phil Soper
Staff member
Corporate Member
Sickens Cetol - the absolute best I know of. Was used on my neighbors mahogany door about 5 years ago - still looks great

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