Q: My 110-year-old front door is delaminating on the exterior. It is solid wood, very heavy and wider than normal. Who can repair this and how?

Washington

A: Judging from the pictures you sent, you probably have a 110-year-old door that someone later tried to repair by gluing veneer to the exterior, perhaps to cover up deep dog scratches or decay.

Doors made that long ago weren’t originally coated with veneer. They were built of solid, natural lumber. The thick perimeter pieces and crosspieces were joined with interlocking mortise and tenon joints. Within that framing, the wide panel pieces were held in a groove, allowing the panels to shrink or swell as humidity fluctuated. Panels could perhaps have been plywood — it certainly existed then — but the framing was always regular wood.

Cracked kitchen tiles? Try a patch.

Most new wooden exterior doors do have veneer, a strategy door manufacturers came up with to cope with the fact that the straight-grain wood they once depended on is now very rare. With the old-growth forests virtually all cut, foresters harvest trees that are much younger, so boards have a higher percentage of what is known as “juvenile wood.” These fibers make boards twist in unpredictable ways. Manufacturers got so many complaints about warped doors that they switched to making doors with stable cores wrapped with thin veneers. Doors might still be “solid wood,” but the core is layered wood, finger-jointed wood, or an engineered material made from wood fibers pressed and glued into a panel. Over that core, manufacturers glue a thin veneer of natural wood. The result is a door that is “solid wood” throughout, but not in the sense of being made from boards as they were cut from a tree.

To find someone to work on your door, you might want to begin by contacting companies that specialize in restoring wood doors and windows. Search online using the words “door restoration” and your city. The Window Preservation Alliance focuses on restoring wooden windows, but many of the same shops that tackle windows also deal with door restoration, so you might also want to look through the directory on its website, windowpreservationalliance.
org.

Sometimes, when veneers are just beginning to lift off, it’s possible to lift an edge using a putty knife, work in waterproof glue (such as Titebond III), and then securely clamp the veneer to the base material until the glue dries. You would need something like a board to spread the pressure between clamps. Christian Kelleher, owner of the Craftsmen Group (301-277-3700; thecraftsmengroup.com) in Brentwood, Md., suggested asking a painter to make the repair. Instead of clamping the veneer in place while the glue dries, the painter could just hammer in a few tiny brads, he said.

Or, when big pieces are coming loose, as on your door, the whole veneer layer can be removed and replaced. Kelleher said that’s probably the approach his shop would take if someone brought a door like yours in for repair, although he also said it would probably be too small a job for his shop to take on unless you brought the door to the shop. He noted the weird butt joint in the veneer piece near the bottom of the door. A good veneer job matches the directions in a solid-wood door, meaning there would be long veneer pieces running from top to bottom on the side rails and shorter pieces running crosswise. “It looks like a bad repair,” Kelleher said after looking at your pictures. The bottom of the door might have decayed, and someone tried to cover it with veneer, he said.

If a repair isn’t possible, you’ll need to replace the door. Select the material carefully based on the sun exposure — west- and south-facing doors are beat up more by the sun than ones that face east or north — and whether the door is protected by a roof overhang. If you don’t want to invest in a modern-style veneered door or switch to one made of steel or fiberglass, see if you can find a used one of the correct size and swing direction (which affects which edges have the hinges and lock) at a store that specializes in salvaged building materials, such as Community Forklift (301-985-5180; communityforklift.org) in Edmonston, Md.

Or you could hire a custom woodworking shop to fabricate a solid-wood replacement door. Kelleher estimated that at $3,000, plus an equal amount to fit the door to your house and add finishes, weatherstripping and hardware.

Whether you restore your door or buy a new one, if it’s wood, make sure to paint all the edges, including the top and bottom. Wood doors fare best with oil-based primer topped by several coats of acrylic paint, at least on the exterior. You might also want to follow advice door manufacturers give to customers who purchase exterior doors with wood veneers. Simpson Door Company warns that its doors with wood on the exterior should be installed only where there is overhead protection from a porch roof or overhang that projects out at least half the height from the lower edge of that roof to the bottom of the door. If your door doesn’t have that protection, consider adding it.

Simpson also warns against coating the exterior side with dark-colored paint. Dark surfaces absorb more heat from the sun than lighter colors, and heat weakens the bond of most types of glue. Steve Orlowski, senior director of standards and technical activities for the Window and Door Manufacturers Association, said most manufacturers have similar requirements.

More from Lifestyle:

How to navigate all the options for refinishing a peeling deck

The trick to getting rid of ants for good (it’s not a spray)

Oil paintings are tricky things to clean on your own