If you’re planning to add a shed to your Baltimore County property, there’s one thing that surprises more homeowners than anything else: Baltimore County has a stricter permit threshold than most Maryland counties. While Anne Arundel County exempts sheds under 150 square feet and Howard County exempts those under 200 square feet, Baltimore County requires a permit for accessory structures over just 120 square feet — one of the lowest thresholds in the state.
That means a standard 10×12 shed — 120 square feet exactly — sits right on the line. And if your property is in a Historic District, a permit is required regardless of how small your shed is.
This guide breaks down everything Baltimore County homeowners need to know before ordering a shed: when a permit is required, what the building guidelines are, how to apply, what documents you need, and the special situations that change the rules.
When a Building Permit Is Required in Baltimore County
A building permit is required for accessory structures greater than 120 square feet in Baltimore County, and for all accessory structures — regardless of size — that are located in a proposed or designated Baltimore County Historic District, in the floodplain, in the Chesapeake Bay Critical Area, or on the Baltimore County Landmarks List. Baltimore County Government
Let’s unpack each of those triggers:
Over 120 square feet: This is the baseline rule for most Baltimore County homeowners. A 10×8 shed (80 sq. ft.) doesn’t require a permit. A 10×12 shed (120 sq. ft.) is right at the threshold — technically not over it, but check with the county to confirm how the line is drawn. A 10×14 (140 sq. ft.) or anything larger requires a permit. Baltimore County is one of the stricter jurisdictions in the state, with a lower threshold than most Maryland counties. MD Sheds
Historic Districts: If you’re in a historic district — and there are many throughout Towson, Catonsville, and other older communities — a permit is required no matter how small your shed. Baltimore County has an extensive list of historic districts and individually landmarked properties, including areas in Lutherville, Reisterstown, Oella, Stoneleigh, Ruxton, and Catonsville. If you live in an older neighborhood, particularly one with pre-war housing stock, check the Historic Districts list before assuming you’re in the clear. MD Sheds
The Chesapeake Bay Critical Area: Properties within 1,000 feet of the Bay, tidal wetlands, or tributary streams fall under the Critical Area Overlay. Baltimore County has extra restrictions for environmentally sensitive areas. If your property is near the water — in communities along the Gunpowder River, Back River, Middle River, or the Bay itself — confirm Critical Area status before planning any accessory structure. Pro Landscape
The Floodplain: Any property in a FEMA-designated 100-year floodplain requires a permit for accessory structures regardless of size. If a structure is located in the 100-year floodplain, it must be firmly anchored and vented. Baltimore County Government
The Landmarks List: Properties on the Baltimore County Landmarks List — a separate designation from the National Register — require permits for all accessory structures. If you’ve ever received correspondence about your property’s landmark status, or if you’re buying an older property, verify this before ordering.
Baltimore County Shed Building Guidelines
This is the section most homeowners skip — and the one that creates the most problems. Baltimore County’s Department of Permits, Approvals and Inspections publishes specific building guidelines that all residential accessory structures must meet. These aren’t suggestions; they’re requirements that apply whether or not a permit is needed.
The structure must be located in the rear yard behind the rear foundation wall line of the principal structure, unless a zoning variance is obtained. This is the front-yard rule: in Baltimore County, your shed goes behind your house, not in front of it or beside it in the front yard. Baltimore County Government
The shed cannot occupy more than 40 percent of the rear yard. If you have a small rear yard, this limits how large a structure you can place there. A 20×20 rear yard (400 sq. ft.) can only accommodate an accessory structure footprint of up to 160 square feet under this rule. Baltimore County Government
Setback from property lines: The structure must be located 2.5 feet from the side and rear property lines. However, any side closer than five feet to the property line requires a one-hour fire-rated safety wall and no openings on that side. The practical implication: placing your shed right at the 2.5-foot minimum creates a construction requirement (fire-rated wall, no windows or doors on that wall) that most prefab sheds are not designed to meet. Keeping the shed 5 feet or more from property lines avoids this complication entirely. Baltimore County Government
If there is an alley, there must be a minimum setback of 15 feet from the centerline of the alley. This matters significantly in older Baltimore County neighborhoods where rear alleys are common — in communities like Catonsville, Towson, and Dundalk, many residential lots back up to alleys. The 15-foot measurement is from the centerline of the alley, not the edge of your property line, so the effective distance from your property line will be less. Baltimore County Government
There is a height limitation of 15 feet for residential accessory structures in Baltimore County. Standard prefab sheds well within this limit, but taller custom builds or two-story structures would need to verify compliance. Baltimore County Government
If the structure is located on a corner lot, it must be situated in the half of the lot furthest from the side street. Corner lots have two street frontages, which limits where accessory structures can be placed. If you’re on a corner, the shed needs to go in the portion of the rear yard that’s away from the side road exposure. Baltimore County Government
If larger than 400 square feet, the structure requires frost-line footings. This applies to larger sheds and detached garages. Frost-line footings in Maryland typically need to extend at least 30 to 36 inches below grade, depending on the county’s frost depth requirements. A standard gravel pad or skid foundation won’t meet this requirement for structures over 400 square feet. Baltimore County Government
A Maryland Home Improvement Commission (MHIC) licensed contractor must be used for the work. This is a requirement that catches some homeowners off guard. Any contractor performing work as part of a permitted project in Baltimore County must hold a valid MHIC license. When you’re working with a shed company, confirm they are MHIC-licensed. Reputable local builders like Pine Creek Structures / MD Sheds carry this licensing as a standard credential. Baltimore County Government
What Documents You Need to Apply
When submitting a permit application for a residential accessory structure in Baltimore County, you must provide an Accessory Structure Letter with a handwritten signature (required for all applications), and a site plan (required for all applications). If the property is served by a well and septic system, the site plan must comply with the Ground Water Site Plan Requirements. Construction plans are required if the structure is 1,000 square feet or over. An Agricultural Verification form must be completed and uploaded if the property qualifies for agricultural exemptions. Baltimore County Government
Here’s what each of those means practically:
Accessory Structure Letter: This is a Baltimore County DPAI form that describes the proposed structure and affirms compliance with the applicable requirements. It requires a handwritten signature — electronic signatures are not accepted for this document. Download the form from the Baltimore County DPAI website before starting your application.
Site plan: A scaled drawing showing your lot boundaries, the location of your existing house and other structures, and the proposed location of the shed with distances to all property lines. The site plan needs to show setback distances clearly. If your property has a well and/or septic system, additional information is required including the location of the well, septic system components, and any nearby neighboring systems.
Construction plans (for structures 1,000 sq. ft. and over): If you’re planning a large detached garage or workshop, you’ll need a full set of construction drawings. For most residential shed projects, this threshold is rarely reached.
How to Apply for a Baltimore County Shed Permit
Baltimore County has moved its permitting process fully online through the CityWorks Pro portal. Plan review in Baltimore County takes 10 to 30 days depending on project type and complexity. Permit Place
The steps:
- Create an account at the Baltimore County Online Permit Portal
- Gather and name your documents according to Baltimore County’s file naming conventions (available on the DPAI website — non-compliant file names will cause your submission to be rejected)
- Complete the online application with applicant information, property address, contractor information, and project description
- Upload all required documents
- Submit and pay the application fee once fees are calculated (Baltimore County accepts Mastercard, Visa, and PayPal)
- Monitor your application dashboard for comments or revision requests from the plan review staff
- Once approved, download your permit — it must be accessible at the job site during inspections
The permit and approved plans must be available on-site for all inspections. If you’re having a shed delivered and installed by a company rather than building on-site, confirm who is responsible for pulling the permit and having documentation available on delivery day.
Additional Permits You May Need
A building permit covers the structure itself. Other work triggers separate permits:
Electrical permit: Required if you’re running power to the shed — wiring, outlets, lighting, or a subpanel. You’ll need a licensed electrician to pull the electrical permit separately from the building permit.
Plumbing permit: Required if the shed will have water lines, a utility sink, or drains.
Mechanical permit: Required for any installed heating or cooling system.
Stormwater/grading permit: A stormwater or grading permit may be triggered if your project adds impervious surface or disturbs soil above county thresholds, and can require engineered controls. If you’re installing a concrete slab or large gravel pad, this is worth confirming with DPAI before breaking ground. Dennisthomasrealtor
Special Situations That Change the Rules
Agricultural properties: Some accessory structures on agricultural properties are exempt from certain Baltimore County Code requirements. An Agricultural Verification form must be completed and uploaded with the Accessory Structure permit application to determine whether the proposed work qualifies. If your property is used for agricultural purposes, this exemption may apply to certain structures — confirm eligibility through the DPAI Agricultural Verification process. Baltimore County Government
Historic Districts and Landmarks: As noted above, any structure on a property in a Historic District or on the Landmarks List requires a permit regardless of size. Additionally, the Historic Preservation section of the county’s Planning Department may review the design and placement of new accessory structures to ensure compatibility with the historic character of the district. In some cases, materials, colors, and architectural details may be subject to review.
Critical Area and floodplain properties: Properties in these overlays face additional review and requirements. Floodplain structures must be anchored and vented. Critical Area properties may have impervious surface limits that affect what foundation type is permitted. Contact the Department of Environmental Protection and Sustainability for guidance specific to your property.
Properties on well and septic: The site plan requirements are more extensive, and the setback distances from the well and septic system components must be clearly documented. Contact the Baltimore County Health Department for specific separation distance requirements before finalizing your shed placement.
HOA communities: Baltimore County’s rules represent the minimum legal requirements. If your neighborhood is governed by an HOA, your CC&Rs may impose additional restrictions on shed size, materials, colors, placement, or appearance. HOA approval is a separate process from the county permit — you need both. Get written HOA approval before ordering or scheduling delivery.
What Happens If You Don’t Pull a Permit
Some homeowners are tempted to skip the permit process on smaller sheds, reasoning that nobody will notice. In Baltimore County, that’s a gamble that rarely pays off.
Baltimore County may impose daily fines for ongoing permit violations. Violations are often uncovered during inspections, neighbor complaints, or property assessments, and officials can issue stop-work orders or demand removal of non-compliant structures. Pro Landscape
Beyond the fines, unpermitted structures create problems when you sell. A buyer’s inspector or attorney will flag any structure that should have been permitted. You may be required to retroactively permit the shed, bring it into compliance, or remove it before closing — all at your expense and on the buyer’s timeline. It’s a complication that can delay or derail a sale entirely.
Keep all permits, approved plans, and inspection records once your shed is complete. These documents prove compliance and protect you if questions arise years later during a sale or insurance claim.
Frequently Asked Questions
Does a 10×12 shed require a permit in Baltimore County?
A 10×12 shed is exactly 120 square feet — right at the threshold. Baltimore County requires a building permit for accessory structures greater than 120 square feet. Whether a structure measuring exactly 120 square feet is “greater than” that threshold is worth confirming directly with the DPAI at 410-887-3900 before assuming no permit is needed. When in doubt, call. Baltimore County Government
What is the minimum setback for a shed in Baltimore County?
The minimum setback from side and rear property lines is 2.5 feet. However, any side of the structure that is closer than five feet to the property line requires a one-hour fire-rated safety wall with no openings on that side. To avoid the fire-rated wall requirement, keep your shed at least 5 feet from all property lines. Baltimore County Government
Can I put a shed in my front yard in Baltimore County?
No. The structure must be located in the rear yard behind the rear foundation wall line of the principal structure, unless a zoning variance is obtained. Baltimore County Government
Do I need a permit for a shed in a Historic District regardless of size?
Yes. A building permit is required for all accessory structures in a proposed or designated Baltimore County Historic District, regardless of size. Even a small storage shed requires a permit if your property is in a historic district or on the Landmarks List. Baltimore County Government
How long does a Baltimore County shed permit take?
Plan review in Baltimore County typically takes 10 to 30 days depending on project type and complexity. Budget at least two to four weeks from application submission to permit issuance for a standard residential accessory structure. More complex projects, or those requiring revisions, will take longer. Permit Place
Can I place a shed right against my fence in Baltimore County?
Not if the fence is on or near the property line. The 2.5-foot minimum setback applies to the property line, not to your fence. If your fence runs along the property line, the shed still needs to be 2.5 feet from the fence — and 5 feet away if you want to avoid the fire-rated wall requirement.
What size shed requires frost footings in Baltimore County?
Structures larger than 400 square feet require frost-line footings. For standard residential sheds under 400 square feet, a gravel pad or concrete skids are typically acceptable foundations. Confirm foundation requirements with DPAI for your specific project. Baltimore County Government
Does my shed contractor need to be licensed in Baltimore County?
Yes. A Maryland Home Improvement Commission (MHIC) licensed contractor must be used for permitted accessory structure work in Baltimore County. When evaluating shed companies, ask directly whether they hold a valid MHIC license. Baltimore County Government
How much does a Baltimore County shed permit cost?
The permit fee is based on the value of the work, so it varies by project. For most standard residential shed projects in the $3,000 to $10,000 range, permit fees typically fall in the $50 to $150 range. Contact DPAI at 410-887-3900 for a fee estimate based on your specific project value.
Serving Baltimore County Homeowners — From Catonsville to White Marsh
MD Sheds — Pine Creek Structures — delivers and installs Amish-crafted sheds, garages, carports, and playsets across Baltimore County and the surrounding region. Our team is familiar with Baltimore County’s permit requirements, knows the MHIC licensing requirements, and can help you navigate the process before your shed arrives.
Whether you’re in Towson, Catonsville, Dundalk, Essex, Owings Mills, Pikesville, or anywhere in between, we’re here to help you get it right the first time.
Use our free 3D Shed Builder to design your shed and get a quote — or call us directly at 1-410-729-8747.
📍 PCS Retail Store 8236C Veterans Highway, Millersville, MD 21108 📧 millersville@pinecreekstructures.com
This guide reflects Baltimore County regulations and procedures as of 2026 and is intended as general information only. Requirements are subject to change. Always verify current permit thresholds, building guidelines, and setback requirements directly with the Baltimore County Department of Permits, Approvals and Inspections (DPAI) at 410-887-3900 or online at baltimorecountymd.gov before beginning any project.