Sheds sit in a funny spot in the rules. They're small, they don't have bedrooms, and nobody lives in them, so many towns go easy on them. But they are still structures on your lot, which brings zoning into play, and the moment you run power to one or make it bigger than a certain size, they can start to look like a small building to the permit office.
This guide covers what to decide, measure and ask before you order a kit or have a prebuilt shed delivered. General guidance only. Your permit office decides.
Why sheds get reviewed at all
Two reasons. First, zoning: towns care where accessory structures sit relative to lot lines, the house and each other, and how much of the lot is covered by buildings and pavement. Second, safety: a larger shed is a building that has to stand up to wind and snow, and a shed with electricity needs wiring done right.
When a permit usually comes up
Many towns exempt small sheds below a certain floor area from a building permit, but still require zoning approval or setback compliance. Others review every accessory structure. The questions that usually decide it:
- Floor area. The single most common threshold.
- Height. Some towns limit accessory structure height, measured in a specific way.
- Foundation. A permanent concrete foundation can change how a shed is treated.
- Electricity, water or heat. These usually bring their own permits.
- Use. A workshop, a home office, or anything people spend time in may be treated differently from storage.
- Location. Front yards, easements, floodplains and septic areas often have extra limits.
What to decide first
- Size and height. Pick the footprint and wall height, and note the peak height of the roof.
- Prebuilt, kit, or built on site. If it's delivered, ask the seller what drawings and specs they can provide for a permit application.
- Foundation. Concrete blocks, a gravel pad with skids, or a slab. Each has different site work and may be treated differently.
- Power. If you want lights or outlets, plan for an electrical permit and a licensed electrician where your town requires one.
- Delivery access. A prebuilt shed needs a clear path. Measure gates and look for overhead wires.
What to measure
- Distance from the planned shed to each property line, the house and any other structure.
- The ground: level, slope, and drainage. Water should move away from the shed, not under it.
- Clearance from septic tanks and fields, wells, and buried utilities.
- The path for delivery or for carrying materials in.
Call 811 before you dig for footings or a slab.
Questions to ask your permit office
- Does a shed of this size and height need a building permit, zoning approval, or both?
- What setbacks apply to accessory structures in my zoning district?
- Is there a limit on height or on total accessory building area?
- Does the foundation type change anything?
- I'd like to add electricity. What permits and inspections does that need?
- What should I submit: a plot plan, the manufacturer's drawings, a foundation detail?
- Are there anchoring or tie-down requirements here?
What offices commonly ask for
- A plot plan with the shed's location and distances to lot lines and the house.
- Shed dimensions and height, often from the manufacturer's spec sheet.
- A foundation description.
- Electrical details if you're adding power.
Common reasons shed applications get sent back
- The shed is too close to a property line or the house.
- The plot plan doesn't show distances.
- The shed sits in an easement or over a septic area.
- Electrical work was planned without a separate permit.
- Height was measured differently from how the town measures it.
Do it yourself or hire a pro?
Shed kits are designed for homeowners, and many people build them over a couple of weekends. Large sheds, sheds on slopes, slabs, and anything with wiring are where a pro helps. If you're adding power, check whether your town requires a licensed electrician. Many do.
Before you order a kit or a prebuilt shed
Sellers are good at showing you colors and door styles. Ask them for the things a permit office cares about instead: the exact footprint including any overhang, the peak height from the ground, the floor and roof load the shed is designed for, the recommended foundation, and whether they provide drawings or a spec sheet for permit applications. If they deliver, ask what access they need, how level the site has to be, and whether they set the shed on your foundation or theirs.
If you're building from a kit, read the whole instruction book before you order lumber for the base. Kits often assume a specific foundation and a level site, and the most common surprise is how much work a sloped yard adds. A shed that sits on a properly drained, level base lasts far longer, and it's much easier to square the walls and hang the doors.
Finally, think about what goes inside. A riding mower needs a wider door and a ramp. A workshop needs light, ventilation and maybe power. Storage for fuel and chemicals has its own safety considerations. Decide the use now, because it affects the size, the door, the floor and, sometimes, the permit.
How Sully helps with a shed
Tell Sully the size, height, foundation and whether you want power. Sully checks your town's zoning and permit pages first and labels each rule with its source. If your town's accessory-structure rule isn't published, the report says so and suggests who to call. The materials list covers framing, sheathing, roofing, trim and foundation materials for site-built sheds, with a waste allowance and any missing dimensions flagged. For a prebuilt shed, the filing packet bundles your plot sketch, the seller's specs and the office's checklist.
Related reading: 5 questions to ask your town before you start and Why permit rules differ from town to town.