Fix a Sagging Deck Gate

Gates sag because gravity wins. Every gate hangs from its hinge side, and that cantilevered weight pulls the free corner earthward over time. Wood dries, screws loosen, and the rectangle becomes a parallelogram. A sagging gate announces itself with dragging corners, scraping cedar planks, and latches that no longer meet their strike. Fixing a gate properly means understanding the physics: you need a diagonal member running from the bottom hinge corner to the top latch corner. That diagonal carries tension and pulls the gate square. The fix takes an afternoon and costs less than thirty dollars. Done right, the gate will outlast the deck boards themselves.

1. Remove the gate and assess the frame. Lift the gate off its hinges or unscrew the hinge pins. Lay it flat on sawhorses or the deck surface. Check for loose screws in the cross-bracing, split rails, or rot in the bottom rail where moisture collects. Tighten any loose fasteners with a drill and replace any screws that stripped out with longer exterior-grade screws.
2. Install a diagonal tension cable. Screw a turnbuckle kit eye-bolt into the bottom rail on the hinge side and another into the top rail on the latch side. Thread galvanized cable through both eyes, pull it hand-tight, then tension it using the turnbuckle until the gate pulls into square. Use a carpenter's square on the corners to verify right angles.
3. Add a solid diagonal brace if the frame is badly racked. If the gate is severely warped or the tension cable alone won't hold it, cut a pressure-treated 2x4 to span diagonally from bottom hinge corner to top latch corner. Notch the ends to fit flush against the existing rails, then fasten with three-inch exterior screws every eight inches. This creates a permanent compression brace.
4. Replace or shim the hinges. Inspect hinge screws for stripped holes. If screws pull out easily, fill the holes with wood glue and toothpicks, let dry, then redrill pilot holes. Alternatively, move the hinges up or down two inches to fresh wood. Use stainless steel screws rated for exterior use — zinc-plated screws corrode in treated lumber.
5. Rehang the gate and check swing clearance. Lift the gate back onto the hinge pins or screw the hinges to the post. Open and close the gate slowly, watching for binding at the latch corner or along the bottom edge. If it drags, plane the bottom edge with a block plane or raise the gate slightly by shimming the bottom hinge outward.
6. Adjust the latch and add a gate spring. Move the latch strike plate up or down to match the latch position. Install a gate closer spring from the top hinge to the gate frame — this keeps constant upward tension and prevents future sagging. Adjust the spring tension so the gate closes gently but firmly.
7. Seal the bottom rail and rehang accessories. Coat the bottom rail with a penetrating deck sealer, especially the end grain. This is where water enters and rot begins. Reinstall any decorative hardware, house numbers, or handles you removed. Check the gate swing weekly for the first month as the wood adjusts.