How to care for a wood front door

How long does a finish last on a wood door?

Anywhere from about a year to about ten, depending on the product and the exposure. The USDA Forest Products Laboratory's Wood Handbook says that, to its knowledge, the best clear exterior coatings "last about ten years when fully exposed" (USDA, chapter 16). Many products last far less in full sun: Waterlox puts its own exterior finishes at 1 to 3 years on sun-exposed surfaces, "much closer to the 1 year mark" in full midday sun (Waterlox), and Masonite says that in frequent direct sun a door's finish "can start to deteriorate within the first year" (Masonite).

Simpson notes that solvent-borne clear finishes cure harder and resist water better, while water-borne clears are more flexible and more UV resistant but cannot be applied below 50°F and need a long cure. It says to use products designed to work together and that "under no circumstances" should a lacquer-based system be used on an exterior door (Simpson).

A new unfinished door should be finished before it sees weather. Simpson requires its doors to be finished within 72 hours of installation, and Sun Mountain says unfinished doors "must be fully finished and sealed on all six sides within 14 days of delivery" (Sun Mountain).

How do sun and an overhang change upkeep?

Shade can double the life of a finish, and a roof over the door cuts the rain it sees. The Wood Handbook says paint on the shaded side of a building "often lasts twice as long as that on a fully exposed, sunny side" (USDA, chapter 16). Waterlox says the finish on "a front door on a covered porch may last many decades" (Waterlox).

Simpson defines an adequate overhang as one that projects at least half the distance from the bottom of the door to the underside of the overhang (Simpson, Know Your Overhang). For example, if the underside of a porch roof is 10 feet above the sill, the roof should project at least 5 feet. Door warranties are often written around that rule, and some go further, so read the one for your door.

• South and west faces get the most sun. Simpson advises examining the finish often on those exposures and expecting to maintain it more frequently (Simpson).
• Dark colors heat the door. The Wood Handbook says darker finishes "result in more solar heating, and so result in more warping and checking of wood than light color finishes" (USDA, chapter 16). Simpson treats paint with a light reflective value below 55 as a dark color with extra requirements, and says dark stains "are not to be used on exterior doors".
• Storm doors in front of a wood door trap heat. Simpson says they "must be vented to eliminate temperature build-up".
• Gutters keep roof water off the door. JELD-WEN recommends clearing them at least once a year (JELD-WEN).
• Very exposed openings: Sun Mountain recommends "a non-wood alternative" for exterior openings with high exposure to direct sunlight or moisture (Sun Mountain). That is a fair warning: a wood door in full sun with no cover is a maintenance commitment.

What does Colorado's climate do to a wood door?

The air is dry, so the wood moves, and the sun is strong on south and west faces. Expect a wood door here to shrink a little in the dry months and to need its sunny faces recoated sooner than its shaded ones. Our wood guide has the USDA moisture figures for Denver and the woods that move least.

Glass is affected by altitude too. Insulated glass is sealed at the factory, and TruStile, a door maker in Denver, says in its high-altitude warranty supplement that "glass without capillary tubes" in products outside its guidelines "is not warranted above 5000 feet" (TruStile). If your door has glass, ask the maker how its glass is built for your elevation.

How often should I inspect and recoat?

Signs it is time to recoat, from Simpson's care page: hairline cracks in the top coat, changes in the color of the finish, flaking or scaling, and a dull or chalky surface (Simpson). Waterlox puts it simply: when the finish "starts to look dull/faded, that is a signal for recoating" (Waterlox).

Recoating a sound finish is a small job. Waterlox says "a light cleaning and a fresh coat will restore the coating and the protection" (Waterlox). If the door is off its hinges, coat the top and bottom edges as well: Simpson says the edges "should be coated with each and every coat of finish".

How do I clean a wood door without hurting the finish?

• Wipe it with a damp, not wet, cloth. Sun Mountain says mild detergents are acceptable, and lists vinegar, citrus-based cleaners, paint removers, window cleaners, brick or siding washes and abrasive cleaners as things that can damage the finish (Sun Mountain).
• Skip the pressure washer. Masonite's door cleaning steps say "never use a pressure washer", because even at the lowest setting water can get into the small gaps around a door (Masonite).
• Never scrape the glass with a razor blade or metal scraper. Simpson recommends that "metal blades never be used to remove materials from glass surfaces" (Simpson), and Masonite says the same.
• Keep solvents such as mineral spirits off the weatherstrip. JELD-WEN says they "may damage or dissolve weatherstrip" (JELD-WEN).

Why does my wood door stick in summer and gap in winter?

Because wood takes on moisture in humid weather and gives it up in dry weather, and a finish slows that exchange without stopping it. Sun Mountain says that in seasonal climates doors "may expand and bind during humid months, then contract and create visible gaps in the drier seasons", and that this is "normal for solid wood construction" (Sun Mountain).

• Light lines can appear around panels as they shrink. JELD-WEN suggests touching them up lightly with a matching finish (JELD-WEN).
• If you plane or trim the door, seal the cut right away. Simpson and Sun Mountain both call for sealing cut edges immediately.
• Indoors, Sun Mountain recommends keeping relative humidity between 40% and 50%, and says it dries its door lumber to 8% to 10% moisture content for climate-controlled homes.
• Painted doors will show fine seams at the joints over time as the parts move. Sun Mountain describes this as natural.

How do I keep the weatherstrip, sweep and sill sealing?

Check them once a year and replace anything that has stopped springing back. JELD-WEN says to replace weatherstrip if it has gaps or is "missing, torn, cracked, brittle, discolored, gummy, or has no bounce back when pressed down" (JELD-WEN).

• Kerf-mounted weatherstrip, the kind pressed into a slot in the jamb, can be reseated if it pulls loose. JELD-WEN suggests a thin bead of silicone sealant in the slot and tape to hold it for 24 hours.
• The sweep on the bottom of the door should meet the sill with light, even contact when the door is closed. Many sills have adjustment screws that raise or lower them.
• Corner pads where the sill meets the jamb close the last gap. Replace them if they are torn or missing.
• Sealant joints between the frame and the siding should be checked for cracks. JELD-WEN says 100% silicone sealant is the most durable but cannot be painted, and to use 100% polyurethane sealant where the joint will be painted.