Gate Installation

A gate into an opening that already exists. The old gate has been taken off, or it is still hanging and past saving. The fence line is unchanged, the posts are already in the ground, and the whole question is whether those posts can carry a gate — which is not the same question as whether they can carry a fence.

A gate into a new opening. There is a run of fence and no way through it. Boards come off, a new hinge post and a new latch post go in, and the fence either side has to be closed back to them so the run is still a run. This is the version people underestimate: cutting an opening removes the panel that was helping to hold the two posts either side of it apart.

Either way the fence stays a fence. This site is repair-first and does not build new fencing — a gate is a component fitted to a line that already stands.

A fence post holds up a panel: the load is static, it is shared with the posts on both sides, and it pushes straight down. A hinge post holds up a gate: the load hangs off one side of it, and every swing works it like a lever. That is why the post that has carried a fence for twenty years is not automatically a post that will carry a gate for one.

What gets checked before anything is hung on it:

• Whether it is sound at grade. Not at hand height — at the ground, where a screwdriver either goes in or doesn't. A post that is soft at the base cannot be improved by better hinges.
• Whether it is big enough in section. Hanging a gate on a post sized for panel work is the most common reason a new gate starts to drop within a season.
• Whether its footing was poured for this. A hinge post wants depth and a collar that sheds water away from the wood rather than holding it against end grain.
• Which way it will want to lean. It leans toward the opening, always, because that is where the weight is. A post already out of plumb toward the gap has been telling you this for a while.

Where the post has to come out, that is its own piece of work and it is written up separately: fence post replacement. The reverse case is worth knowing too — a sound post in good ground is a real saving, and it is the first thing we look for.

Everything a gate does wrong mechanically comes back to one relationship: the load on the hinges is the weight of the leaf multiplied by how far out it reaches. Make the gate wider and you have not just added boards, you have lengthened a lever.

That gives the three things worth getting right:

• The diagonal, and which way it runs. A wooden gate with no working diagonal slowly turns from a rectangle into a parallelogram — the latch corner drops. A timber brace works in compression and has to run from the bottom of the hinge side up to the top of the latch side. A cable and turnbuckle works in tension and runs the other diagonal. Fitted the wrong way round, each of them does nothing at all, and a cable fitted the wrong way is one of the more common things we find on a sagging gate.
• Hinges sized to the leaf, fixed into the frame. Fasteners have to land in the structural members, not in the cladding boards screwed to their face. Cladding is not a fixing.
• A latch that tolerates movement. Wood swells through a wet winter and shrinks through a dry summer, and the opening moves with it. A latch with adjustment in it goes on working; one set to a perfect fit in August stops closing in February.

Where an opening is wide — a driveway, a side access big enough for a machine — a single leaf is a long lever by definition. A pair of leaves with a drop rod into the ground halves the reach and gives the closed gate a fixed centre point, and on a wide opening that usually beats one heroic leaf.

Repair is still the default here, and most gates that drag or won't latch are repairable: that is the whole of gate repair, and it is the cheaper conversation. A new gate earns its place in a narrower set of cases:

• The frame has racked and the joints have opened. Once the corners have moved and the mortises or the screwed joints have loosened, pulling it back square puts the load onto joints that have already given up.
• The bottom rail or the hinge stile has gone soft. These are the two members that get wet and stay wet. Hardware fixed into either of them is hardware fixed into nothing.
• The post has failed and the gate is the same age. If a rotten hinge post is coming out anyway, a gate built for the old post position is often not worth refitting to the new one.
• The gate was never right for the opening. Too heavy, too wide for one leaf, no diagonal, hinges a size down. These gates get repaired repeatedly and go on failing, because the fault is the specification rather than the wear.

Repairing or replacing a gate in place usually leaves alone the three things the local rules actually regulate — height, material and position. A gate that is taller than the fence, one built out of something the fence isn't, or a new opening onto the street can each move the answer, and the three cities here treat gates in the front strip differently from gates down the side.

The figures, by city and with the code sections they come from, are on the guide: fence rules and permits. It is also the page to read before cutting a new opening on a corner lot or anywhere near a driveway.

Gate installation by town: Palo Alto, Menlo Park and Mountain View, plus the other Peninsula towns on the service-area list.

Can the new gate hang on the posts that are already there? Often yes, and it is the first thing worth establishing, because a sound hinge post is the largest single saving in the job. What decides it is the post at the ground rather than the post at eye level, its section, and whether it is already leaning toward the opening.

Why does a new gate need a new post when the fence doesn't? Because the loads are different in kind, not just in size. A fence post is pushed straight down and braced from both sides; a hinge post is pulled sideways by a weight hanging off it, repeatedly, every time somebody walks through.

My last gate sagged within a year. Will this one? Only if it repeats the same three mistakes: a diagonal that isn't doing anything, hinges undersized for the leaf, and fixings landing in cladding. A gate that sags quickly is almost never a mystery.

Do you build the fence as well? No. This is a repair business — fences and decks that already stand. A gate fitted into an existing line, or an opening cut into one, is where that stops.

Photograph the opening straight on with a tape or a broom laid across it for scale, the base of the post on each side, and the fence run for a few feet either way. If there is a gate there now, add the hinge side and the latch side closed. Where the ground falls across the opening, one shot from the side along the fence line tells us more than any measurement you could send. Or call the number at the top of the page.