A well-constructed garden gate is a functional and attractive feature that provides security, privacy, and kerb appeal. Building one from scratch with treated timber is an achievable DIY project that produces a gate tailored precisely to the opening size and style required.

Design and Materials

The basic structure of a timber gate comprises two vertical stiles, which are the outer vertical members; two or more horizontal rails connecting the stiles; a diagonal brace from the bottom hinge-side corner to the top latch-side corner; and the infill boards fixed to the rails. Choose pressure-treated softwood or a naturally durable hardwood such as iroko or European oak for outdoor use. Common sections for a standard garden gate are 75mm by 50mm for stiles and rails and 100mm by 22mm for the infill featheredge boards or pickets.

Sizing the Frame

Measure the gate opening carefully, allowing a clearance gap of around 5mm on each side between the gate and the posts, and 10 to 15mm at the bottom to avoid the gate dragging on an uneven ground surface. The overall frame size is the opening width minus the clearance gaps on each side. If the opening is not level or plumb, allow for this in the bottom rail height to maintain the appearance of the gate while accommodating the ground level variation.

Constructing the Frame

Lay the two stiles parallel on a flat surface, spacing them to the planned gate width. Mark and cut the top and bottom rails to length. Fix the rails between the stiles using external-grade wood screws and waterproof wood glue at each corner, checking the assembly is square with a diagonal measurement before the glue sets. Both diagonals of the frame should be equal for it to be square. Cut and fix the diagonal brace from the bottom hinge corner to the top latch corner, mitre-cutting the ends to fit tightly against the rails. Fix the brace with screws through the rails.

Adding the Infill

Fix the infill boards vertically to the front face of the rails using two screws per board at each rail. Space the boards consistently using a spacer cut from scrap timber if gaps between boards are required. Featheredge boards are overlapped rather than spaced. Check alignment and plumb regularly as boards are added to avoid a cumulative drift. Finish the top of the boards with a consistent cut, whether flat, arched, or pointed, to create the desired appearance.

Hanging the Gate

Use heavy-duty external hinges appropriate for the gate's weight, fixed to both the gate stile and a sound timber post. Double-check the hinge positions for level and plumb before fixing permanently. Adjust until the gate swings freely without catching. Fix the latch at a comfortable height, typically around 900mm to 1000mm from the ground.

Summary

A garden gate is built from two stiles, two or more rails, a diagonal brace from bottom hinge corner to top latch corner, and infill boards. Use pressure-treated or naturally durable timber. Check squareness before the glue sets. Treat all surfaces before hanging. Use appropriate-weight hinges and a quality latch. The diagonal brace is the key structural element that prevents the gate from sagging over time.