Permits
Do I need a permit?
Patterns, not determinations. Complexity is a planning hint so you know when to call the city first.
- FenceHeight, material and where the fence stands decide it; the fence permit brief gives Austin's and Los Angeles's lines.Low
- DeckCommonly required when the walking surface is elevated, attached, or over a stated size. Ground-level platforms may be exempt — locally.Medium
- ShedOften exempt below a local size/height cap if it stays a simple accessory building without utilities. Confirm the cap.Low
- PergolaNo permit under the model code for a freestanding pergola up to 200 sq ft; attached to the house, it needs one.Medium
- Retaining WallNo permit under the model code up to 4 ft from the bottom of the footing, unless the wall supports a surcharge.High
- PatioOften none for at-grade hardscape. Raised structural slabs, work in easements, and covered patios are the usual triggers.Low
- GazeboNo permit under the model code for a freestanding gazebo up to 200 sq ft of floor area; hardwired wiring for a fan or lights needs one.Medium
- DrivewayCommon for new curb cuts and widening. In-kind replacement may be lighter — locally.Medium
- PoolRequired for almost every pool: the model code exempts only a prefabricated pool less than 24 in deep.High
- GarageRequired under the model code once a detached garage passes 200 sq ft of floor area.High
- ADUAlways: an ADU is a dwelling unit, and no exemption covers one.High
Fence, Deck, Shed, Pergola, Retaining Wall, Patio, Gazebo, Driveway, Pool, Garage and ADU are the permit briefings currently cleared for search publication. Other projects stay in the research queue, unpublished, until their official-source review is complete.
What the model code leaves off the permit list
Building codes in the U.S. are mostly adopted, not written from scratch. The International Code Council says its International Residential Code, the model code for houses, is in use or adopted in 49 states, the District of Columbia, Guam, Puerto Rico and the U.S. Virgin Islands. A state or city adopts an edition and amends it. Section R105.2 of that code lists the work that needs no building permit, and it is where the numbers people search for come from. These are its backyard items, as the 2024 edition states them; the 2021 edition, still in force in many places, has the same figures.
| Work | No building permit when |
|---|---|
| Shed, playhouse or other one-story detached building | Floor area 200 sq ft or less, unless it is a storm shelter. The IBC's line for sheds is 120 sq ft. |
| Fence | Not over 7 ft high. The 2024 IBC leaves pool barriers out of this. |
| Retaining wall | Not over 4 ft, measured from the bottom of the footing to the top of the wall, unless it supports a surcharge: extra load on the soil it holds back. |
| Water tank on the ground | Up to 5,000 gallons, and no taller than twice its width. |
| Sidewalk or driveway | Exempt from the building permit. Work in the public right-of-way needs the road owner's permit. |
| Prefabricated swimming pool | Less than 24 inches deep. |
| Swings and other playground equipment | Exempt. |
| Deck | 200 sq ft or less, no more than 30 in above grade at any point, not attached to the house and not serving its required exit door. |
The section opens with a sentence that is easy to skip: an exemption from a permit is not permission to build in violation of the code or of any other law or ordinance. Setbacks, easements, HOA covenants and utility locates apply to exempt work too. The International Building Code, written for buildings other than houses, sets its shed line at 120 square feet instead of 200, which is where the lower figure in many answers comes from, and its 2024 edition leaves swimming pool barriers out of the fence exemption.
Your city’s own list is the one that binds. Austin keeps the residential code’s shed and deck figures but adds a 15-foot height limit for sheds and a flood-hazard condition for both; Los Angeles lets any fence but a masonry wall or a pool barrier reach 10 feet without a permit; Houston cuts the shed line to 120 square feet and lets a fence reach 8 feet; San Diego exempts a retaining wall only to 3 feet, measured from the top of the footing. Each briefing sets the model’s answer beside Austin’s and Los Angeles’s, and the table below adds Houston, Phoenix and San Diego.
Permit-free limits, city by city
One row per project: the line under which no building permit is needed, in the model code and in each checked city’s own text, as its city page cites it. Five cities, five different lists: no two agree on every line. To test your own numbers against the Austin and Los Angeles lines, use the permit checker.
| Project | Model code | Austin | Houston | Los Angeles | Phoenix | San Diego |
|---|---|---|---|---|---|---|
| Fence | Up to 7 ft (IRC R105.2) | Up to 7 ft; 6 ft along a public right-of-way; none in a floodplain | Up to 8 ft, if not masonry, concrete or electrified | Up to 10 ft, pool barriers excepted; 3 ft 6 in for masonry or concrete | Up to 3 ft, pool barriers aside; 3 to 7 ft takes a zoning-only permit | Up to 7 ft, pool barriers aside; zoning caps each yard |
| Deck | 200 sq ft, 30 in above grade, freestanding, not at the required exit door (IRC R105.2) | The same four limits, and not in a flood hazard area | 200 sq ft, 30 in above grade, detached, not the required exit | Up to 30 in above grade, not over a basement; no area limit | Up to 30 in above grade, not over a room; no area limit | 200 sq ft, 30 in above grade, detached, not the required exit |
| Shed | 200 sq ft, one story, detached (IRC R105.2); 120 sq ft for tool and storage sheds (IBC 105.2) | 200 sq ft, one story, 15 ft high, no plumbing | 120 sq ft, one story, detached; not a storm shelter | 120 sq ft, one story, no heating, plumbing or wiring | 200 sq ft, one story, detached; shade structures included | 120 sq ft of projected roof, one story, on the ground |
| Patio | Names sidewalks and driveways, not patios (IRC R105.2) | Concrete flatwork outside the right-of-way | Flatwork outside the Infrastructure Design Manual | No patio line; an awning to 4 ft from the wall is exempt | No slab line; a freestanding shade cover to 200 sq ft | No slab line; a cover to 300 sq ft in the RS and RX zones |
| Driveway | Sidewalks and driveways exempt (IRC R105.2) | Exempt outside the right-of-way; approach reviewed by the city | Flatwork outside the Infrastructure Design Manual; the approach needs a permit | Exempt to 30 in above grade; a curb cut needs city approval | Up to 30 in above grade; right-of-way work needs a permit | Up to 30 in above grade; right-of-way work needs a permit |
| Pergola | Freestanding: up to 200 sq ft; attached: not on the list (IRC R105.2) | No pergola line; its accessory line is 200 sq ft and 15 ft | No line; the nearest is the 120 sq ft accessory structure | Freestanding, up to 400 sq ft, outside any fire district | A freestanding shade structure to 200 sq ft, no cantilever | No line; the nearest is the 300 sq ft patio cover |
| Retaining Wall | Up to 4 ft from the bottom of the footing, no surcharge (IRC R105.2) | Up to 4 ft, no surcharge, not in a flood hazard area | Up to 4 ft from the bottom of the footing, no surcharge | Up to 4 ft, no surcharge or sloping earth, never on a slope over 1 in 5 | Up to 40 in from the top of the footing, no surcharge | Up to 3 ft from the top of the footing, no surcharge |
| Pool | Prefabricated and under 24 in deep (IRC R105.2) | Prefabricated under 24 in, or any storable pool | No exemption; ask about a storable pool | Up to 24 in deep and 250 sq ft of water surface | Prefabricated, above ground, under 18 in deep, up to 5,000 gallons | Prefabricated, walls above grade, up to 5,000 gallons |
| Gazebo | Up to 200 sq ft of floor area, one story, detached (IRC R105.2) | No gazebo line; accessory structures to 200 sq ft and 15 ft | No line; the nearest is the 120 sq ft accessory structure | No gazebo line; sheds and similar uses to 120 sq ft | Freestanding, one story, up to 200 sq ft | No line; the nearest are the 120 sq ft shed and 300 sq ft patio cover |
| Garage | Up to 200 sq ft of floor area, one story, detached (IRC R105.2) | 200 sq ft and 15 ft, as for any accessory structure | Only inside the 120 sq ft accessory line | No garage line; sheds and similar uses to 120 sq ft | No line; the nearest is the 200 sq ft shed | No line; the nearest is the 120 sq ft shed |
| ADU | None: a new dwelling unit takes a permit (IRC R105.2) | None; new construction on SF-1 to SF-3 lots of 5,750 sq ft or more | Always needs a permit | None; a complete application decided within 60 days | Always needs a permit; two per house lot | Always needs a permit, decided without a hearing |
The three questions that decide most permits
Building departments rarely ask what you are building. They ask how big it is, how tall it is and where on the lot it sits. A six-foot rear fence, a 100-square-foot shed and an at-grade patio are routinely exempt from a building permit in U.S. cities; the same fence in the front yard, the same shed with wiring or the same patio with a roof are routinely not. Each briefing above is organized around the measurements that flip the answer.
A permit is one of several approvals
Permit-exempt does not mean unregulated. Zoning still sets setbacks and lot-coverage limits, a recorded easement still gives a utility the right to remove what sits on it, an HOA still reviews materials and colors, and 811 needs a few days' notice to have the lines marked before anything is dug. Work in the public right-of-way — a driveway apron, a sidewalk — is permitted by whoever owns the road, not by the building department at all.
What a permit costs
There is no national permit fee; each city sets its own, and the two with checked pages set them in different ways. Austin charges fixed review and inspection fees by type of work. A fence that needs a permit is billed at the small-projects review rate, $146.15, and a driveway approach in the right-of-way carries a $220.00 review and a residential inspection of $577.51 plus $97.28 per driveway (FY 2026-27, effective October 1, 2026). The permit cost guide sets out every residential fee line and how long a city may take to decide.
Los Angeles calculates the building permit fee from the project’s valuation, and for some work LADBS publishes the rate it values it at: $10 per square foot of wall for a masonry fence, $14 for concrete, and $16 per square foot for a patio cover (valuation table effective August 17, 2015). Each city’s page answers every project with a permit brief: Austin and Los Angeles.
Reading the complexity label
Low means the typical version of the project is often exempt and the exceptions are easy to name. Medium means one measurement — usually height or attachment to the house — commonly decides it. High means plans, engineering or more than one department are the norm. The label is a planning hint about when to call the city first; only the city can say what applies to your parcel. Run the permit checker to see the pattern for your project and state before you call.