Rain Resistance of Wood Panel Entry Doors

Woodworkers discuss the practicality of making a wood entry door leak-proof in a rainstorm. June 2, 2009

I just fitted a custom entry door - four flat panels, with custom moulding, solid core construction with laminated panels. We primed the exterior (Ben Moore penetrating oil-base), but a storm over the weekend showed rainwater coming in underneath every panel. The millwork Co. said we should have painted all the topcoats before exposing it to the weather, but it seems to me the panels aren't fitted properly, and now the panels have warped enough that no paint will "seal" it - who's right and what’s to be done?

Forum Responses
(Architectural Woodworking Forum)
From contributor D:
What are the specs you provided the supplier with? What specs did he supply you with? What is the supplier's warranty? What is the experience level of the supplier, and did they make it in their shop? What does 'solid core construction with laminated panels' mean? Does this mean solid wood type wood, or solid strandboard, LVL, MDF type wood? Are laminated panels of plywood or?

There are many more questions than answers until there is some more information. I do not think the additional topcoats would have made that much difference, especially long term, given the little bit I know about it. I also think it always a good idea to protect a door from weather until finish is 100% complete and cured.

From contributor Z:
Primer is just that - primer. Most all door manufacturers will state that all six sides of a door need to be sealed and finished. A Full Lite storm door would be a good idea.

From contributor M:
No wood door should be exposed to direct rain. I don't care how you build or paint a door it won't hold up to that type of extreme treatment for very long and was probably not the right door for that location.

From contributor L:
Bad design choice for the location. The panel to frame joint will never be totally watertight. It can't be and still fufill it's function. The panel needs to be able to shrink and swell in the frame, I.E. move. Either protect the door from the elements, including the sun or use a fiberglass door.

From contributor D:
Whether a frame and panel door can be in the weather or not depends upon many things. Most BigDoorCo warranties have a formula to calculate exposure and overhang to determine if a door is warranted or not. Most warranties will exclude black or 'dark' finishes because of the heat they can generate. Without clarification from the OP, one cannot address his situation. My suspicion is marginal construction and install, since that is 95% of the problems I see, but I don't know.

As for the larger question, can exterior wood doors be reliable, I would say yes - if: If proper woods and methods are used, including designed to shed water, integral sticking or splined, double rabbeted bolection molds. Sealed panels held tightly by the sticking or molding and caulked if the panels are held in by molded frames.

If the door is hung properly and weatherstripped and has a proper sill. The finish must also help on the side of sealing, as does the periodic maintenance of the finish. Most small quantity door makers emulate BigDoorCo details and methods. I think if you are going to the expense of custom wood doors, then you should push the envelope some and take it further than BigDoorCo accountants would ever permit. Epoxy end seals, use superior joinery and woods and premium weatherstripping and finish, as well as proper hardware. Follow up maintenance.

None of this is cheap, nor should it be. Read the BigDoorCo warranties online, and then you see why those doors are cheap - the warranty almost never applies. While I have supplied many unwarranted situations, I have never had a customer back away - if they want wood, they will have wood. They may be finishing once a year, but they have wood.

One situation is south facing, no overhang, full sun and rain, and the door is recoated once or twice a year. 12 years, and while it looks older, it still functions perfectly. Wood exterior doors are certainly not for the masses, but it is not correct to rule them out in every exterior situation. Rain is not extreme treatment - it is normal. Accept it, design for it, and build for it.

From contributor M:
I have the upmost respect for your knowledge and skills, but come on, water coming through every panel on a four panel door - that is too much water! There is a place for everything. The lines aren't as clearly drawn as you like to see it, high dollar or low budget. There is a middle ground and that's where most shop owners and most customers reside, like it or not. In this instance assuming average customer, average means, average house, the design probably does not accommodate an average wood door.

From contributor D:
Contributor M - you are probably right, middle ground-wise, but I sometimes have a hard time acknowledging it. Middle of the road budget, application and experience it may well be. If that is where the world resides, then so be it. Lack of a simple, good design is most at fault, since a protected opening adds comfort to both the visitor and resident, and will easily allow for a longer lived and widely varied entrance.

Mediocrity exists, I have no doubt. However, I don't think that means we all need to roll over in unison and submit to the onslaught of plastic doors. Good design is always the better foundation and protection from mediocrity. Cheap has forced us to forego a simple porch roof, and has, by the dint of unintended consequences, forced the plastic door upon us. We now see the problem as that of wood doors instead of the fault of design (or lack of). I know I'm unable to change the world (especially aware with election at hand), but I still like to kick and fuss a bit. Maybe it will improve as a result, maybe not.

From contributor G:
I agree with both contributor D and contributor M. But in terms of the leaky situation, the primer does not seal the door. Never has, never will. It is not the job of a primer to seal a door. It is designed to promote the mechanical bond between wood fibers and the paint finish final coats. As such, the primer has merely opened the wood grain to allow for moisture to interact inside the door. The perimeter of the panels is the culprit of the leak and should be sealed properly to prevent the migration of moisture.

Plastic and steel are not a good choice either, but I'm a wood door guy at heart, plastic and steel would provide longer protection, but at a cost of both warmth and architectural diversity. Proper design, finish and maintenance are the keys to the solution here.