Shed Permit Basics

This guide is general information, not legal advice. Every state, county and town writes its own rules, and a homeowners association can add more. What follows explains how those rules are usually structured, so you can have a short, useful conversation with your building department and get a clear answer for your address.

Two different approvals

People say "permit" for two separate things, and a shed can need one, both or neither:

• A building permit is about how the shed is built: structure, foundation, wind and snow loads. It is issued by the building department and usually involves plans and an inspection.
• Zoning approval is about where the shed goes and how big it is on the lot: distance from property lines, height, lot coverage, and whether accessory buildings are allowed there at all. It is handled by the zoning or planning office.

A shed can be exempt from a building permit and still have to meet every zoning rule. That is the most common surprise, and it is why a small shed built a foot from the fence can still end up with a violation notice.

Size thresholds

Most US building codes are based on the International Residential Code, which the International Code Council says is in use or adopted in 49 states and the District of Columbia. Section R105.2 of the 2021 edition exempts one-story detached accessory structures, other than storm shelters, from a building permit when the floor area does not exceed 200 sq ft. The same section says the exemption does not let you build in violation of the code or of any other local law.

States and towns adopt the code with their own amendments, and the limit moves. California's residential code sets it at 120 sq ft. Elgin, Illinois, asks for a permit before work starts on any shed and puts every project through zoning approval. So the 200 sq ft figure is where the conversation starts, not where it ends. Building in Canada? Cities there set the line in square metres, and snow loads come from the National Building Code: see shed permits and snow loads in Canada.

Here is where our free plans fall, measured on the outside of the floor frame:

Overall height from grade to the ridge on a skid foundation with 8 ft walls and a 6/12 roof, as calculated by the shed designer. Check how your town measures height. Elgin, Illinois, for example, measures a gable roof to the middle, between the eaves and the ridge, not to the peak.

Zoning and setbacks

Zoning rules for accessory buildings usually cover some of these:

• Setbacks: minimum distances from the side and rear property lines, and sometimes from the house or other buildings.
• Location: many towns allow sheds only in the side or back yard, not between the house and the street.
• Height: a maximum height for accessory buildings, which matters for tall walls and steep roofs.
• Lot coverage: a limit on how much of the lot can be covered by buildings, counting the house.
• Easements: strips of land reserved for utilities or drainage, where building is often not allowed at all.
• Flood zones: in the model code, buildings and structures in a mapped flood hazard area follow a separate set of flood rules (section R322).

One real example: Elgin's shed guide keeps sheds at least 4 ft from any other building, outside every easement, and no taller than 15 ft measured to the middle of the roof, and it says the setbacks from property lines depend on the zoning district. Your numbers will be different; the list of things to ask is the same.

On top of the town, a homeowners association can have its own rules on size, color, materials and placement. Elgin's guide points out that private covenants can be stricter than city zoning and that the city does not enforce them. Read the covenants or ask the board.

Power, water and other triggers

Even when the shed itself is exempt, some work usually is not. Section R105.1 of the model code asks for a permit to install or change any electrical, gas, mechanical or plumbing system it regulates, and to change the occupancy of a building:

• Electrical: running a circuit to the shed normally needs an electrical permit and an inspection. Ask who is allowed to do the work.
• Plumbing and gas: a sink, a toilet or a gas heater brings in plumbing or mechanical permits.
• Use: a shed you sleep in, work in with customers, or rent out is a change of use, and the building department will look at it as more than a storage shed.
• Size and height: going over the exemption limit, or building a second story or loft floor, can bring the full building permit into play.

What to ask the building department

Call or visit the permit counter with the size you have in mind. These questions cover almost everything:

1. Do I need a building permit for a detached storage shed of this floor area, and how do you measure floor area?
2. Do I need a zoning permit or approval even if no building permit is required?
3. What are the setbacks from the side and rear property lines and from the house?
4. What is the maximum height for an accessory building, and how is it measured?
5. Is a skid or block foundation acceptable, and do you require anchoring? Some places do: Prince William County, Virginia, for example, lets small sheds skip a permanent foundation only if they are anchored against wind.
6. What design snow load, wind speed and frost depth should I use for my address? The model code leaves these to each jurisdiction to set.
7. What do I need to submit, and will there be an inspection?

Write down the answers with the name of the person you spoke to and the date. If you get an answer by email, keep it.

If you do need a permit

For a small shed, the application is usually light: a site plan showing the shed and the distances to property lines and other buildings, like the sketch at the top of this page, and a drawing of the shed with its size, height and framing. The PDF for any of our free plans includes the framing elevations, floor framing, rafter details and a full materials list, which is often enough to start the conversation; the builder's plan from our shed designer does the same for your own size. Some departments will want more detail, a specific foundation, or an engineer's stamp; they will tell you.

Fees and turnaround times vary widely, so ask when you call. Build the waiting time into your plan and use it to order materials and prepare the site.

With the answers in hand, start with a solid base: how to build a shed foundation.