It’s one of the first questions we hear after someone picks out a shed: Do I need a permit for this? The short answer is: it depends on the size — and where you live. Here’s what you actually need to know before you break ground.
The State Rule: 200 Square Feet Is the Line
Massachusetts state building code sets a clear threshold. Any structure — including accessory structures like sheds, garages, and greenhouses — that exceeds 200 square feet requires a building permit from your local building department. So a 10×20 shed? That’s 200 square feet exactly, which means it falls right at the line. A 12×20 is 240 square feet — permit required. A 10×16 comes in at 160 square feet — no state-level building permit needed. That’s the baseline. But here’s where it gets more nuanced.
Your Town May Have Its Own Rules
Staying under 200 square feet does not automatically mean you’re in the clear. Massachusetts cities and towns have their own zoning bylaws, and those bylaws can — and often do — impose requirements that go beyond state building code. Even if your shed doesn’t trigger a state building permit, your town might still require a zoning permit or approval, minimum setback distances from property lines and other structures, restrictions on the total percentage of your lot that can be covered by structures, height limits for accessory buildings, or requirements tied to the type of foundation used. Westfield is a good example. The city requires a Determination of Zoning Applicability to be completed and approved before a building permit will be issued — and that requirement applies regardless of shed size. Even a small shed that falls well under the 200-square-foot state threshold still needs to go through the zoning determination process first. Westfield isn’t unique. Many towns across Massachusetts have front-end zoning steps that aren’t obvious from the state code alone. It’s always worth a call to your local zoning or building department before you assume your project is permit-free.
Why This Matters Before You Buy
Getting the permit question sorted out before you purchase a shed — not after — saves you from real headaches. We’ve seen homeowners fall in love with a 12×16 design, place the order, and then discover their town requires a minimum 15-foot setback from the rear property line that leaves no room for it. A few steps that go a long way: call your local building or zoning department and ask what’s required for a shed of a given size and where on your lot it can go — it’s a five-minute call that can save weeks of back-and-forth. Have a rough sense of where you’re thinking of placing the structure and how far it sits from your property lines before you call. And ask specifically about accessory structures under 200 square feet. Don’t assume a small shed is automatically permit-free.
What About Permits and Resale?
It’s worth thinking ahead. If you ever sell your home, an unpermitted structure — even a small one — can come up during inspection and create complications. Pulling the proper permits, even when they’re not strictly required by state code, protects your investment and prevents surprises down the road.
Frequently Asked Questions
Not necessarily. The 200 square foot threshold is the state-level building permit trigger, but many Massachusetts towns have their own zoning requirements that apply regardless of shed size. Some towns require a zoning permit or zoning determination even for a small shed. Always check with your local building or zoning department before ordering.
A Determination of Zoning Applicability is a form some Massachusetts towns — including Westfield — require you to complete and have approved before a building permit application will be processed. It establishes that your project complies with local zoning bylaws. If your town requires it, you’ll need to file it first, regardless of your shed’s size.
Setback requirements vary by town and zone. Most Massachusetts municipalities require sheds to be positioned a minimum distance from property lines, fences, and the main dwelling. In Western MA, setbacks of 5 to 10 feet from property lines are common for accessory structures, but your town may differ. Your local zoning office can give you the exact numbers for your parcel.
We can advise on common permit practices for Western MA towns and help you understand what questions to ask your local building department. For permitted garage builds, our team handles the construction side and can guide you through the process. For shed deliveries, we recommend calling your local building or zoning department to confirm requirements before your delivery date.
