Why Does A Gate Sag?

Asian Contemporary Style Wooden GateBeing married to a (wood) gate builder has been quite an education! Because 360 Yardware deals with gate hardware every day, I thought it might be interesting to marry the two issues and discuss why a gate sags and what can be done to prevent your gate from sagging.

I must add a disclaimer that my husband the gate builder comes to gate building from furniture-making. Therefore, he is a crazy stickler for structure, function, and joinery. And it’s rubbed off on me, so I’m biased toward really high quality gates (and, of course, really high quality gate hardware).

To have the best possible non-sagging gate 10 years in the future, here is the key: buy or build a well-constructed gate and have it installed by a skilled installer. In other words, the reason that gates sag is because the gate falters or because the installation wasn’t done well enough.

A Well-Constructed Wooden Gate

What is a well-constructed gate and how do you know you’re buying one? I’m going to describe two ends of the spectrum; there are endless variations within those bounds.

A well-built wood garden gate will have a furniture-quality joint: mortise and tenon, lap joint, etc. Think about your home’s front door: it’s built with nice tight joints and will last years and years, even being opened and closed many times a day.  A quality wooden gate should do the same, though it likely won’t last as long as a front door because a gate is subject to sun, rain, snow and wide temperature fluctuations. You won’t see any metal fasteners on a furniture-quality gate (screws or nails) because the joints do that work.

Well-built wooden gates are absolutely more expensive to buy (~$500-$1500); however, if you’ll get a 10-year life out of that gate versus a 3-year life out of a cheaper gate, it might just be worth the expense (and the hassle of re-installing a gate every few years). And don’t discount the value that an architecturally complementary gate adds to your home and your curb appeal. I’ve seen so many million dollar homes with shoddily constructed gates that make me scratch my head and wonder why they would do such a thing to their beautiful house.

Driveway Gate with 10" Dark Bronze Thumb Latch & Dummy Handle

Now to the second category of wooden gates: the ‘carpenter gate’.  This is your typical picket or panel gate with a diagonal bracing piece across it. It’s usually constructed with 2×4’s as the frame. They are always nailed or screwed together. A simple butt joint (two flat surfaces butted up against each other and screwed/nailed together) is generally not going to hold a gate together for the long haul. I don’t want to disparage gates that have simple butt joints, but in the world of simply built gates, the vast majority will have joints that won’t last. It all depends on your gate builder. An experienced gate builder can probably make a sturdy carpenter gate. But there’s little likelihood that a carpenter gate is going to last the way a high-quality gate will.

A Saggy Gate

A Saggy Gate

What About Anti-Sagging Kits? The bottom line is this: if you buy a gate from someone who uses an anti-sag kit, you should consider having someone else build your gate. That would be like buying a pair jeans with big patches sewn on the knees. If you buy quality jeans and care for them, you shouldn’t need patches.

Over time and with the gate opening and closing, the nailed or screwed joints will begin to loosen. This will cause the gate to “sag” or more accurately, lean to one side, away from the failing joint.

How to Install a Wooden Gate (Well)

A knowledgeable gate installer is a worthwhile investment. But remember that even the best installer can only do so much with a sub-par gate. Here are some factors during the installation process that can help prevent gate sagging and give you a smoothly operating gate for years to come.

  1. Post Size: Though I don’t think anyone’s compiled this kind of data, I would venture a guess that using too small of a gate post is the major culprit in gate sagging. What makes a gate post too small? The size of the post should be related to the size and weight of the gate. My husband’s recommendation is always a 6×6 post for standard-sized gates (~42″x70″). For driveway gates, especially those with integrated steel frames, he always recommends steel posts. The key to post installation is that it be set deep enough in the ground and firmly set in concrete. If the post is not big enough to support the gate, it will start to pull in the direction of the gate. In addition, if the post isn’t set firmly in concrete, the post is going to wiggle loose bit by by in the ground. If there is one area of a gate installation that you’re going to “over-engineer” let it be the post.
  2. Hinge Choice: Choosing a hinge that will support the weight and style of your gate is crucial to a long-term installation. We’ve written a blog post about hinge choice that covers everything you need to know. An undersized hinge’s screw can slowly work loose from the post with the weight of the gate swinging back and forth. Heavy duty gate hinges are affordable and easy to install.
  3. Gate Latch Choice: Gate latches are not created equal. Choosing quality heavy duty gate hardware will help keep your gate in good shape. How? A quality self-latching gate latch (in other words, a spring-loaded gate latch) works so that when you push the gate closed or the wind slams it closed, the latch-arm hits the strike, rises up, and clicks itself down into the catch on its own. Without a self-latching latch, that same gate would slam against the post, bounce back open, and slam back. Over and over. A free-swinging gate is not a good thing for any part of your installation.

See our collection of Heavy Duty Gate Hinges and Gate Latches.