· Michael Blair
A gate that has dropped at the latch side is racking — the rectangle deforming into a parallelogram. The fix is either the post or the brace, and the brace is very often installed the wrong way round.
Which way the brace goes
A wooden compression brace must run from the bottom of the hinge side up to the top of the latch side. That way the gate’s weight pushes along the brace, and wood is strong in compression.
Installed the other way, the brace is in tension, and wood plus fasteners resist tension poorly. It is the single most common gate mistake.
Cable braces are the opposite
A steel cable or turnbuckle brace works in tension only, so it runs the other way — from the top of the hinge side down to the bottom of the latch side.
Getting either backwards produces a gate that sags no matter how it is adjusted, and the turnbuckle version at least lets you take up the slack.
- Wood brace: bottom hinge corner to top latch corner
- Cable brace: top hinge corner to bottom latch corner
- Hinges bolted through, not screwed into end grain
- Gate post larger and deeper than line posts
- Anti-sag kits work but do not fix a leaning post
When it is the post, not the gate
Check whether the gate is still square before blaming it. If the frame is square and it still will not latch, the hinge post has leaned, and no amount of bracing the gate fixes that.
Gate posts take a constantly changing load and need to be bigger and deeper than the rest of the fence.
Hardware that lasts
Heavy strap hinges spread load across more of the frame than small butt hinges. Bolts through the post and frame hold far better than screws into end grain.
In Middle Tennessee humidity, hot-dipped galvanised or stainless hardware is worth the difference — plated hardware bleeds rust down a fence within a couple of years.