What's inside
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A simple garden gate is a useful weekend project if you keep the opening square, choose outdoor-rated lumber and leave room for seasonal movement. This plan makes a roughly 36-inch-wide, 42-inch-tall gate from cedar or pressure-treated boards, hung between existing posts. It uses a diagonal brace to resist sag and basic butt hinges. Measure your opening before buying materials; an out-of-square opening or weak post can turn an easy build into a frustrating one.
Contents
Check the opening before you shop
Measure the gap between the posts at the top, middle and bottom. Use the smallest measurement to size the gate, and leave about 1 inch of total clearance so it can swing without scraping. For a 37-inch opening, for example, make the gate about 36 inches wide. Check the opening’s height at both sides too, especially if the ground slopes.
Push each post firmly. If one moves, reinforce or replace it before hanging a gate; a sagging post is not fixed by stronger hinges. Check that the posts are plumb and that there is room for the gate to swing clear of plants, gravel and uneven ground. For a gate over soft soil, allow more bottom clearance than you would over a level paved path.
Materials and hardware
For a basic 36-by-42-inch gate, plan on two 2-by-4-inch horizontal rails, two 2-by-4-inch vertical stiles, one diagonal 2-by-4-inch brace, and enough 1-by-4-inch boards for the face. Actual lumber dimensions are smaller than the names: a 2-by-4 measures about 1½ by 3½ inches. Buy outdoor-rated screws, two strap hinges and a latch suited to the gate’s weight.
Cedar is lighter and naturally rot-resistant, but it costs more and can split near screw ends. Pressure-treated lumber is usually cheaper and widely available, but it is heavier, may be wet when purchased, and can twist as it dries. The trade-offs are practical, not complicated:
| Material | Good choice when | Watch for |
|---|---|---|
| Cedar | You want a lighter gate and prefer to leave the wood unfinished or stain it. | Higher cost; predrill near ends to reduce splitting. |
| Pressure-treated lumber | Budget and ground-level durability matter more than weight or appearance. | Buy straight, dry boards if possible; wet stock can shrink or warp. |
For treated lumber, use fasteners rated for contact with treated wood; ordinary interior screws can corrode. A box of exterior deck screws is suitable for many wood-to-wood connections, but follow the fastener maker’s guidance for treated stock and hinge installation. A pair of outdoor-rated strap hinges should be sized for the gate’s weight and fastened into solid framing, not just the face boards.
Cut and assemble the frame
Tools: tape measure, square, saw, drill-driver, clamps and safety glasses. A circular saw is convenient, but a hand saw works for a few cuts. Cut the rails and stiles to fit your measured gate size. For a 36-inch-wide gate framed with two 1½-inch stiles, cut the rails to 33 inches if they fit between the stiles. Set the stiles to the planned height, then check the assembled frame against the opening before adding boards.
Lay the frame on a flat surface. Square it by measuring both diagonals; adjust until the two measurements match. Fasten each rail to the stiles with two exterior screws at each end, predrilling near board ends. Add the diagonal brace from the bottom hinge-side corner up to the top latch-side corner. This direction helps carry the latch-side load back toward the lower hinge. Cut the brace to fit snugly between the frame members, then screw it in place.
Attach the face boards with small, even gaps—about ⅛ inch is a reasonable starting point for dry lumber. Spacing helps water drain and leaves room for minor swelling. If using wet pressure-treated boards, avoid tight, edge-to-edge spacing; they will shrink as they dry and open the gaps later. Keep board ends aligned with the frame and use screws long enough to bite into the rails without poking through.
Hang the gate and test the swing
Set the gate in the opening on temporary blocks to establish the bottom clearance. A helper makes this safer and faster. Position the hinges on the gate’s frame, with one near the top and one near the bottom, and fasten them through the stiles. Attach the hinge halves to the post, using screws or bolts appropriate to the hinge and post. Avoid placing all the fasteners into a thin edge or a cracked section of the post.
Remove the blocks and open the gate slowly. It should swing freely without rubbing, and the latch should meet its catch without lifting or pulling the gate sideways. If the latch side drops, check that the frame is still square and that the diagonal runs from lower hinge side to upper latch side. Tighten loose fasteners and correct hinge alignment before adding a stronger latch. For a simple finish, a basic outdoor gate latch is often enough; a lockable latch is useful only if you need the added security.
Finish and maintain it
Unfinished cedar can weather to gray; that is a cosmetic change, not automatically a problem. If you want to preserve its color, apply an exterior stain or sealer according to the label. Let pressure-treated lumber dry before coating if the product instructions call for it; finishing too soon can prevent good adhesion. Keep finishes off hinge pivots and latch parts.
After the first month, check screws and swing clearance. Repeat the check after a wet season or freeze-thaw cycle. Tighten hardware if needed, but do not force a screw that spins in a worn hole; move to sound wood or repair the hole. A small gate is not meant to brace a leaning fence post, hold back livestock or carry a person’s weight. Within those limits, straight stock, a square frame and a correctly placed brace matter more than buying expensive hardware.