Fence and Gate Rules in Los Gatos and Los Altos: What You Can Actually Build

A solid cedar fence along the road frontage of a Los Gatos hillside lot. Six feet, board on board, stained dark. Across most of the town that fence is legal and needs no building permit at all. Inside the Hillside Area it breaks three separate rules at once, and the first anyone tends to hear about it is after the posts are set.

Fence rules in this part of the valley are not one rule. They change at the town line, they change again at the hillside boundary, and as of 20 August 2026 they change once more within five feet of your house. Here is what applies where.

Los Altos publishes exact numbers, and they are stricter than six feet in three places

The City of Los Altos sets a general maximum of six feet for any fence, wall or similar structure (Municipal Code §14.72.020). Three exceptions matter on almost every residential lot.

Nothing inside the required front-yard setback may exceed four feet. On a corner lot, nothing within five feet of the exterior side property line may exceed four feet either. And the city planner can flip which yard counts as the front on a corner lot, but only where that reading matches how the house itself is oriented.

That last provision is worth asking about before you design anything on a corner. It is the difference between a four-foot fence and a six-foot one along a stretch of frontage that may be the most private part of the yard.

Los Gatos splits the town in two, and the hillside half has its own vocabulary

Outside the Hillside Area, residential properties in Los Gatos get six feet plus one foot of lattice on top, seven feet total, on or within any property line. That is the more generous of the two towns.

Inside the Hillside Area, four additional rules apply, and that cedar fence would have broken three of them:

• Six feet is a hard ceiling. No lattice allowance on top.
• Any fence within 20 feet of a property line adjacent to a street must be open view fencing as the Town defines it in §29.40.0310.
• On lots of one acre or more, perimeter fencing must be wildlife friendly, again per the Town’s own definition.
• Buck and rail, double, and solid fences are prohibited. Chain link, welded wire and wire mesh are allowed only where coated green, brown or black and supported by a wood frame.

Most of the trade treats those last two as a nuisance to be worked around. We think that reading is wrong, and the reason is design rather than compliance. A solid six-foot board fence on a sloped lot steps down in visible increments, throws a hard shadow line across the grade, and reads as a wall you are hiding behind. Open-view fencing on the same slope keeps the borrowed view of the hills that the lot was bought for. The rule is not costing you anything you wanted.

Full detail sits in Town Code sections 29.40.030 through 29.40.0330, with more in the Site Elements chapter of the Hillside Development Standards.

The visibility triangles, which almost nobody designs to

Los Altos writes its sight-distance rules as geometry, not as guidance. Two triangles govern:

• At the intersection of two streets, nothing over three feet inside a 25-foot triangle.
• On either side of a driveway where it meets a street, nothing over four feet inside a 15-foot triangle.

The driveway rule extends to your neighbour’s driveway as well. If an adjoining property’s driveway sits within 15 feet of where a rear property line meets the secondary street line on a corner lot, the same restriction lands on your fence. It also applies when that adjoining lot is still vacant, which catches people on new-construction streets.

Los Gatos handles the same problem with words rather than dimensions: fences, walls, gates and hedges may not exceed three feet inside a required front or street-side yard, a driveway view area, a traffic view area, or a corner sight triangle, unless the Town Engineer and Community Development Director grant an exception.

Note that hedges count. A row of pittosporum planted to eight feet inside a corner triangle is the same violation as a fence, and it arrives two years after anyone would think to check.

Where a permit is actually required

In Los Gatos, a wood fence six feet or under needs no building permit. A property-line wall built of concrete masonry units, precast panels or stucco does, under Town Code §29.10.020. The material decides it, not the height.

Retaining walls are where this gets expensive. Los Gatos exempts retaining walls under four feet measured from the bottom of the footing to the top of the wall, but the exemption does not apply to any wall supporting a surcharge, and the Town lists water, dirt and sand as surcharges. A retaining wall that is not holding back soil is a garden feature. Anything doing real work needs a permit, whatever its height.

This is the single most common surprise on a hillside project, and it is worth knowing before the design is priced rather than after. If your fence is going on top of a retaining wall, the wall is its own permitted structure and the combined height is what the planning counter will be looking at. Our hardscape and retaining wall work is usually where that conversation starts, and the multi-level hillside approach is often cheaper than one tall wall.

The wildfire rule that changed three weeks ago

On 20 August 2026 the California Board of Forestry and Fire Protection approved the state’s Zone 0 defensible space regulations, the first of their kind in the country. Zone 0 is the first five feet measured out from the exterior walls of a home, and the rules treat it as an ember-resistant zone rather than a landscaped one.

For fences and gates, two provisions matter:

• No new combustible fence or gate inside Zone 0.
• Where a fence or gate attaches to a structure, or comes within a foot of one, it needs a five-foot noncombustible section at that junction.

Repairs to existing combustible fencing may continue in the same material. New work may not. The rules apply in State Responsibility Areas and in Very High Fire Hazard Severity Zones inside Local Responsibility Areas, which covers a substantial share of the Los Gatos hillside. New construction complies on adoption. Existing homes get a phased schedule: roughly three years for clearing and vegetation work, five years for the fence and gate changes, run by the local fire authority.

The design answer is not a metal fence. It is a short metal or masonry return where the fence meets the house, then the material you actually wanted for the run beyond it. That detail costs very little at design stage and is awkward to retrofit into a finished fence line.

The regulation goes to the Office of Administrative Law for review and publication before it is formally in effect, so confirm current status with your fire authority before you rely on a date. The design implication does not change either way.

What the code lets you do that most homeowners never ask for

Los Altos §14.72.020 grants three allowances that rarely show up on a plan:

Up to two feet of lattice on top of a rear or side yard fence, taking it to eight feet, provided the material is at least fifty percent open to light and air when viewed horizontally and the city planner finds it compatible with the fence below. Decorative columns or post caps up to one foot on fences adjoining a street or walkway, typically spaced at least eight feet apart. And a single arbor-style entry element over a walkway, up to eight feet high, five feet wide and three feet deep, which is explicitly excluded from lot coverage.

That arbor exclusion is the useful one. It is an eight-foot entry moment on a six-foot fence line that costs you nothing against your coverage budget. It is also where a custom gate earns its keep, and it pairs naturally with the way we handle driveway entrances, pillars and entry lighting.

One prohibition to note: barbed wire, electric and similar fencing may not be built within ten feet of any property line adjoining a street or public walkway.

Who pays for the fence on the property line

California Civil Code §841 presumes that adjoining landowners share equally in the benefit of a boundary fence and are equally responsible for the reasonable cost of building, maintaining or replacing it.

The presumption comes with a procedural condition that people skip. Before incurring the cost, you must give each affected neighbour 30 days’ prior written notice, and the notice has to describe the problem, the proposed fix, the estimated cost, how you propose to split it, and the timeline. Build first and ask later and you have given up the strongest part of your position.

A court can rebut the presumption where the cost is disproportionate to one owner’s benefit, where it exceeds the increase in property value, where equal shares would work real hardship, or where the fence is excessive and driven by one owner’s preference. An elaborate ironwork gate does not become a shared cost merely by sitting on a shared line.

Frequently asked questions

How tall can my fence be in Los Gatos? Six feet plus one foot of lattice outside the Hillside Area. Six feet with no lattice allowance inside it. Three feet inside a required front or street-side yard, driveway view area, traffic view area or corner sight triangle.

How tall can my fence be in Los Altos? Six feet generally. Four feet inside the required front-yard setback and within five feet of the exterior side property line on a corner lot. Three feet inside the 25-foot street-intersection triangle and four feet inside the 15-foot driveway triangle.

Do I need a permit for a fence? In Los Gatos, not for a wood fence six feet or under. Yes for a property-line wall in CMU, precast or stucco. Retaining walls need a permit whenever they support soil or water, and the four-foot exemption does not rescue them.

Does the new Zone 0 rule mean I have to replace my wood fence? No. Existing combustible fencing can be repaired in kind. New fences and gates may not be combustible within the first five feet of the house, and any fence meeting the house needs a five-foot noncombustible section at the junction. Existing homes are on a phased schedule of roughly three and five years.

Does my neighbour have to pay half? Presumptively yes under Civil Code §841, if you gave them 30 days’ written notice covering the problem, the fix, the cost, the proposed split and the timing. The presumption can be rebutted, and it does not extend to a fence built well beyond what the boundary needs.

Before you set a post

The rules that catch people are not the six-foot number everyone knows. They are the hillside overlay, the sight triangles, and now the first five feet against the house. Every one of them is easier to design around at the sketch stage than to argue about at the counter.

If you are planning a fence, gate or entry in Los Gatos or Los Altos, we are happy to look at the lot before anything is drawn. Our custom gate and fence work starts with the property line and the code that governs it, which is a duller opening than most and saves a great deal later. See also our service-area pages for Los Gatos and Los Altos.

Code citations current as of September 2026. Ordinances change; confirm with the Town of Los Gatos Community Development Department or the City of Los Altos Planning Division before you build.