Troubleshooting and Repair of Glue Failure in an Exterior Door

A raised-panel Hickory exterior door behind a glass storm door is coming apart from the effects of solar heat and moisture condensation. What can be learned (or done) in this situation? June 3, 2007

I have a client with a front door made of hickory. The panels on the door are splitting at the glue joints, and the rails and stiles are also beginning to come loose. This is probably happening because they installed a storm door, and the sunlight, combined with a southern exposure and humidity (the client said that at one point condensation was so bad that water was collecting and running out on the porch) make the area between the door and storm door into a sauna. The client has since removed the seal at the bottom of the storm door, and problem is not as severe, though I have advised that they need to consider some other methods of removing heat buildup.

What is the best way to fix the door? The only way I can see is to disassemble the door, clean out the joints, and reglue the entire thing. However, only the joints on the bottom half of the door are loose. Any suggestions on how to loosen the rest of the joints? Or, should I advise the client to simply get another door?

Incidentally, the man who made the door has since died, and I have no idea of what kind of glue was used, however, I would guess it was probably a basic woodworking glue.

Forum Responses
(Adhesive Forum)
From contributor F:
If I were in your shoes, I'd advise the client against repair. It opens a can of worms and could conceivably, in the long run, cost more than a new door. What you can do is give them all the pros and cons and let them make the decision.

From contributor D:
I would also think repair would likely be difficult to impossible, and once you touch it, you own it - like it or not. The joints that are not loose will not necessarily want to come apart, making it impossible to disassemble the thing.

It sounds as if improper glues were used on the door, and perhaps even poorly dried wood. Replacement would be advised, this time using someone that has a good track record of successful exterior door construction and the peripheral knowledge to properly advise as to finish and protection.

No matter what, if a storm door is used, it must be vented at the top and bottom to let out heat buildup. A homeowner will not like this since it sort of defeats the purpose of the storm door, but problems will arise if the sun shines on this entry and it has a tight storm. It becomes a solar collector, and temps over 180 degrees are not uncommon. Doors without protective overhang are not warranted by any manufacturer, therefore some houses must have plastic or stamped metal doors - which will also age prematurely.

When faced with similar situations, I stand back, fold my arms, shake my head, and say, "I don't know what you ought to do." Then politely excuse myself. There is neither money nor glory in this type of work.

From the original questioner:
Thanks for the input. After taking some more time to think about this project, I have to agree that it's not a thing with which I wish to tangle. Too many chances for things to go wrong. It's a shame, because it was really quite an attractive door.

On a general note, and just out of my own curiosity, is there any way to loosen a glue joint that has already set, other than by simply cutting it apart? I generally use Titebond II.

From contributor F:
Not to my knowledge.

From contributor D:
Hide glue is the only glue I can think of that is intentionally reversible. Used in antique conservation and musical instrument repair for its reversibility.

From contributor B:
First, in my opinion, panel doors are not satisfactory as exterior doors. But whether used inside or outside the home, the panels must be free to allow for wood movement due to the normal expansion and contraction caused by varying moisture content from season to season. If the panels are fixed or glued, then they will crack, and even joints may crack. The only thing you can do at this point is to fill any cracks and finish the door using a good primer and several coats of exterior paint (acrylic latex or oil based) and hope for a few years of use. It is also possible that the door initially had a higher moisture content due to storage environment and much of that wood movement is over and the door has adapted to its location.

From contributor D:
I'm curious as to why you think panel doors are not satisfactory as exterior doors? Any limitations or exclusions to this usage? I wonder what would be used in place of, say, a six panel door. I have seen panel doors last for up to centuries. I have also seen them fail after a year. The reasons for either outcome are more than numerous, but the failures should not cause a blanket avoidance, when ample evidence suggests that it is possible to use such doors in exterior situations.

From contributor B:
Panels in paneled doors are meant to be free to move with seasonable changes in moisture, which results from the environment or the initial change in the wood's MC while the wood is adapting from the shop to the job site. Panels that are glued in can't move, therefore any difference in the expansion of the panel and the adjacent cross-grained wood will put stress on one or the other, and cracking can result. Or the exceptions occur when glue joints crack and the panel can move without cracking. Paneled doors can be made to work in an exterior environment reliably if the panels can move freely. If finish is put over the joints as in varnishing or painting, the panels can either become fastened (and crack) or move (cracking the finish and losing protection to the joint).

From contributor D:
I think you misunderstood. I did not mention anything about gluing panels in place, and neither did anyone else. I did discuss the difficulty of disassembly of glued joints. Without saying it, I assumed that we all knew the joint to be disassembled would be a mortise and tenon or dowel joint at the rail/stile connections, and not the panel in plow slip (that is - no glue) joint that retains the panel in the door. Once the rail/stile joint was disassembled, the panels would then come away from the plows.

So, I'm still curious. Are panel doors not to be used in exterior situations? If so, what is to be used in same? Could there be a set of circumstances that would permit a paneled door, and what would they be?

From contributor B:
I don't prefer paneled doors from my own experience, but others may not agree. From the initial post it was stated that the joints were coming loose also… which is another example of wide joint cross-grained failure in a paneled door, due to wood movement possibly. While it wasn't mentioned that the panels weren't glued in, they do become fixed when a finish coat is applied. Then one of two things are likely; either the panels crack or the finish seal cracks around the panel, leaving the panel and the joints relatively unprotected from water/moisture intrusion. I prefer solid core exterior doors or metal or fiberglass insulated doors as a way around joint cracking and high maintenance concerns.