Do I need a permit for a shed in Hillsborough, California?
Sheds must normally meet Hillsborough's full setbacks: 25 feet from the street line and 20 feet from side and rear lot lines. One small shed (40 sq ft or less, 6 ft tall or less) may go in a setback if it's at least 5 feet from the lot line, 40 feet from any neighbor's house and the neighbor agrees in writing. All exterior construction needs design review.
| Street-line setback | 25 ft [3] |
| Side/rear setback | 20 ft [4] |
| Shed allowed in setback | One, max 40 sq ft [5] |
| In-setback shed height | Max 6 ft [6] |
| In-setback shed distance from lot line | At least 5 ft [7] |
| Max size per accessory building | 1,000 sq ft [9] |
| Height (outside setbacks) | 22 ft at setback line, 32 ft max [12] |
Setbacks
A shed, tool house or other accessory building is a "structure" under the zoning code [1], and no structure may sit in a required setback area unless an exception applies [2]. The street-line setback is 25 feet from the street line [3], and the interior (side and rear) setback is 20 feet from every other lot line [4]. So a typical shed goes in the buildable area at least 20 feet from side and rear lines. On lots with a house of 8,000 sq ft or more, the setbacks are 15 feet larger in total.
Small-shed exception
You may place one enclosed structure in all of your setback areas combined if it is no larger than 40 square feet [5] and no more than 6 feet high [6], is at least 5 feet from any lot line [7], at least 40 feet from any neighboring house and more than 25 feet from any street line, and the adjoining neighbor states in writing that they don't object [8].
Size and coverage
There is no limit on the number of accessory buildings, but each covered one is capped at 1,000 sq ft [9]. Accessory buildings count toward the lot's floor area ratio (25% of net lot area for the first acre) [10][14] and toward structural lot coverage if they have more than one wall and a roof [11]. Open gazebos, trellises and open pergolas are excluded.
Height
Outside setbacks, buildings must fit within the building envelope: 22 feet at the setback line, sloping inward at 45 degrees to a 32-foot maximum [12].
Permits and review
All exterior changes, including new construction, need design review by the ADRB or by planning staff for minor projects [13]. The local sources don't state a shed building-permit size threshold; the state building code exempts one-story sheds of 120 sq ft or less from a building permit, but zoning setbacks and design review still apply.
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Next steps
- Get a survey and plot the 25-ft street and 20-ft interior setback lines to find where a shed can go.
- If using the small-shed setback exception, get your adjoining neighbor's written no-objection statement and confirm the 40-ft distance to their house.
- Check your remaining floor area and lot coverage allowance, since covered sheds count toward both.
- Contact the Planning Division ((650) 375-7422) for design review, then the Building Division ((650) 375-7411) about whether a building permit is needed.
Common questions
- Do I need a permit for a shed in Hillsborough, California?
- All exterior construction needs design review. Contact the Planning Division for design review, then the Building Division about whether a building permit is needed.
- How far must a shed be from the property line in Hillsborough, California?
- Sheds must normally be 25 feet from the street line and 20 feet from side and rear lot lines.
- Can I put a small shed in the setback in Hillsborough, California?
- Yes, one shed of 40 sq ft or less and 6 ft tall or less may go in a setback. It must be at least 5 feet from the lot line and 40 feet from any neighbor's house, and the neighbor must agree in writing.
- How big can a shed be in Hillsborough, California?
- Each accessory building can be up to 1,000 sq ft. Outside setbacks, height is 22 ft at the setback line and 32 ft maximum.
California state rules for sheds and accessory buildings
Where a shed can go (setbacks, height, lot coverage, front-yard limits) is set by your city or county zoning code. The state sets the building-permit baseline:
- Permit exemption: the 2025 California Residential Code (R105.2) exempts one-story detached accessory structures used as tool and storage sheds, playhouses and similar uses if the floor area is 120 sq ft or less. Bigger sheds need a permit, and electrical or plumbing work needs its own permit. Some cities have amended these thresholds.
- Other exempt work in the same list includes fences up to 7 ft and decks up to 200 sq ft that are no more than 30 inches above grade and not attached to the house.
- Exempt doesn't mean unregulated: zoning setbacks, HOA rules and easements still apply, and some cities require a zoning clearance even for small sheds.
- Turning a shed or garage into living space is covered by the state's ADU law (Gov. Code §66314). An existing accessory structure converted to an ADU needs no added setback, and new ADUs need no more than 4-foot side and rear setbacks (see ADUs).
- Wildfire areas: in a state responsibility area, owners must keep 100 feet of defensible space around buildings (Pub. Res. Code §4291). Local fire-hazard rules may limit what you can build or store near structures.
- Coastal zone: a new structure is "development" and may need a coastal development permit (Pub. Res. Code §30106).
What the ordinance says
- Sec. 17.08.270, Municipal Code Title 17 Ch. 17.08 Definitions (17.08.245 Short-term rental; 17.08.285 Transitory lodging; 17.08.270 Structure), p. 1
Examples of a structure include, but are not necessarily limited to, any dwelling, building, second unit, garage, carport, tool house, guest house, green house, pool house, satellite dish antenna, solar collector panel, tree house or other play structure, swimming pool, tennis court, play court, and deck.
- Sec. 17.24.010(A), Municipal Code Title 17 Ch. 17.24 Required Setback Areas, p. 1
Except as otherwise set forth in these general rules, no structure placed, erected, or constructed on private property shall be located in the setback areas as described in Section 17.24.020.
- Sec. 17.24.020(A), Municipal Code Title 17 Ch. 17.24 Required Setback Areas, p. 1
The street-line setback area is that twenty-five foot wide strip of land that is bounded on one side by the street line and on the other side by a parallel line on the lot and twenty-five feet distant from the street line, such parallel line continuing until either end of it abuts a lot line.
- Sec. 17.24.020(C), Municipal Code Title 17 Ch. 17.24 Required Setback Areas, p. 1
The interior setback area is that twenty-foot wide strip of land that is bounded on one side by a lot line that is not a street line and on the other side by a parallel line located on the lot and twenty feet distant from the lot line, such parallel line continuing until either end of it abuts a lot line.
- Sec. 17.24.010(B)(5), Municipal Code Title 17 Ch. 17.24 Required Setback Areas, p. 1
In the total combined setback areas of a lot, one enclosed structure not exceeding forty square feet in floor area if:
- Sec. 17.24.010(B)(5)(a), Municipal Code Title 17 Ch. 17.24 Required Setback Areas, p. 1
The structure is no more than six feet high; and
- Sec. 17.24.010(B)(5)(b), Municipal Code Title 17 Ch. 17.24 Required Setback Areas, p. 1
The structure is no closer than five feet from any lot line; and
- Sec. 17.24.010(B)(5)(e), Municipal Code Title 17 Ch. 17.24 Required Setback Areas, p. 1
The adjoining affected property owner(s) (i.e., the owner(s) whose property is adjacent to the proposed structure) has indicated in writing that the affected owner has no objection to the proposed location.
- Sec. 17.32.050, Municipal Code Title 17 Ch. 17.32 Residential Structure Size and Lot Coverage, p. 1
There is no limitation on the number of accessory structures that may be allowed on a lot; provided, however, that each covered accessory structure shall not exceed one thousand square feet in floor area, except as otherwise set forth in Sections 17.52.020(C)(5) and (C)(6).
- Accessory Buildings and Structures, Development Standards - Annotated Excerpts from the Zoning Ordinance (Revised July 2026), p. 11
The floor area for accessory buildings is considered part of the total floor area for the lot.
- Sec. 17.32.060(A)(1), Municipal Code Title 17 Ch. 17.32 Residential Structure Size and Lot Coverage, p. 1
Structural coverage consists of areas of the lot covered by a house, a garage, a carport, and any other accessory structure having more than one wall and a roof.
- Building Envelope, Development Standards - Annotated Excerpts from the Zoning Ordinance (Revised July 2026), p. 7
The envelope starts at existing grade at all setback lines, rising to a height of 22 feet directly above grade, then extending at a slope of 45 degrees inward (away from the property line) to a maximum height of 32 feet measured from a warped plane parallel to existing grade and reflective of the topography.
- Development Standards (introduction), Development Standards - Annotated Excerpts from the Zoning Ordinance (Revised July 2026), p. 2
All exterior changes are subject to Design Review approval (including re-roofing, landscape installations, color or material changes, fencing, additions, and other new construction), either by the Town’s Architecture and Design Review Board (ADRB) or by Planning Staff (for minor projects only).
- Sec. 17.32.020(B), Municipal Code Title 17 Ch. 17.32 Residential Structure Size and Lot Coverage, p. 1
The total covered floor area shall not exceed twenty-five percent of the net lot area for the first acre plus fifteen percent of the net lot area over one acre.