Why the back door of your shop keeps sagging, and what a continuous hinge fixes

What's actually happening when a door sags

A standard door hangs on three or four butt hinges. Each one carries the door's weight through a few small knuckles and a handful of screws. On a light interior door, that's plenty. On a steel back door that gets propped open for deliveries, slammed by a draft, and used fifty times a day, those few screws take a beating. They loosen, the screw holes in the frame wear out, and the door slowly drops.

You'll notice it first at the latch. The bolt stops lining up with the strike plate, so you have to lift the handle or shoulder the door shut. After that, the bottom corner starts scraping the floor or the threshold, and the gap along the top of the door gets wider than the gap at the bottom.

Try these fixes first

Before you call anyone, spend ten minutes on the cheap checks. Tighten every hinge screw. If any of them just spin, they've stripped out, and a longer screw that reaches the framing behind the jamb sometimes bites where the original couldn't. Look at the door closer, if there is one, because a closer fighting a sagging door makes the damage worse. If the door still drags after that, the hinges are the limit, not the screws.

What a continuous hinge does differently

A continuous hinge runs the full height of the door instead of sitting in three spots. The door's weight spreads along the entire edge rather than concentrating at a few points, so there's no single screw hole to wear out first. Valley Lock & Key sells and installs SELECT Products aluminum geared continuous hinges. The geared design keeps the leaves moving together as the door swings, and the manufacturer designed them for both new construction and retrofit work.

The shop's own description is plain about where these fit: high-traffic commercial doors in schools, offices, warehouses, storefronts, hotels, and public and industrial buildings. That's a decent description of a busy back door, too.

Saving an old door instead of replacing it

The shop's continuous hinge page says that if your door no longer fits the frame and won't close right, a continuous hinge will usually help. They back that up with a photo from a job at Irwin Research: a worn steel commercial door with a new aluminum continuous hinge running down its edge, which the shop describes as a hinge saving an old door.

A new door and frame is a big project. A hinge that lets the door you already own close properly again is often a much smaller one. It won't fix a door that's badly bent or a frame that's pulled out of the wall, and a locksmith will tell you so when they look at it. For a door that's simply tired, it's worth asking about.

A new door lasts longer with the right hinge

You don't have to wait for the sag. The shop also recommends adding a continuous hinge to a new door in a high-traffic spot so it stays true for longer. If you're putting in a new steel door at the back of a shop, the hinge decision is better made before the first delivery than after the first scraped floor.

How long does the work take?

According to Valley Lock & Key, they can install a hinge on most doors within a couple of hours, and they carry the product in stock. They serve Yakima, Ellensburg, and Toppenish. The shop also says that every customer who has had a SELECT hinge installed has invited them back to do more doors. Doors differ, so a call with a description of yours gets you a better answer than a general one.

• How tall and heavy is the door, and what's it made of?
• Does it swing in or out, and is there a closer or an exit device on it?
• Is the frame solid, or is the jamb itself loose or cracked?
• How many times a day does the door get used?

Have those answers handy and call (509) 575-3631, or bring a photo to the counter at 3402 W Washington Ave #118 in Yakima. The shop is open Monday through Thursday 8:00 AM to 4:30 PM and Friday 8:00 AM to 4:00 PM.