Building Setbacks & Zoning in Gaithersburg, MD

Gaithersburg maintains 95 local ordinances across all categories, and 3 of those deal specifically with building setbacks & zoning. Here is a breakdown of what the city actually requires, what is prohibited, and where Gaithersburg falls on the strict-to-permissive spectrum compared to other cities.

Structure Height Limits

Gaithersburg caps residential buildings at 3 stories and 38 feet across its R-A, R-90, R-6, RB and R-20 detached-home standards, while townhouse and multifamily forms in denser zones may rise to 4-6 stories.

Key details: R-A/R-90/R-6/RB residential cap: 3 stories, 38 feet. R-90/R-6 non-residential cap: 45 feet. R-20 townhome cap: 4 stories, 48 feet. R-20 multifamily cap: 6 stories, 72 feet. R-H high-density zone: No fixed height cap (N/A).

Exceeding a zone's height maximum without an approved waiver, variance or master-plan-defined allowance is a Chapter 24 zoning violation, treated as a municipal infraction under Section 1-9; the city planning and code administration can refuse to issue or can revoke a building permit for plans that exceed the applicable table's height standard until the design is revised or relief is granted.

Lot Coverage Limits

Gaithersburg zoning caps impervious and building lot coverage by district. The low-density R-A zone allows 50% impervious and 35% building coverage, while the medium-density R-90 zone allows 70% impervious and 50% building coverage.

Key details: R-A impervious cap: 50% of lot area. R-A building cap: 35% of lot area. R-90 impervious cap: 70% of lot area. R-90 building cap: 50% of lot area. Front-yard impervious cap: 35% (R-A and R-90).

Building or paving beyond a zone's coverage maximum without an approved site plan or variance is a zoning violation enforceable as a municipal infraction under Section 1-9, and the city can withhold or revoke a building or occupancy permit until the site is brought into compliance or a variance is granted through the standard zoning variance process in Chapter 24.

Setback Rules

Gaithersburg's residential zoning tables set minimum front, side and rear setbacks by district: 30/15/30 feet in the low-density R-A zone, tightening to 20/5/20 feet in the medium-density R-90 zone.

Key details: R-A front setback: 30 feet minimum. R-A side/rear setback: 15 ft / 30 ft minimum. R-90 front setback: 20 feet minimum. R-90 side/rear setback: 5 ft / 20 ft minimum. Commercial/industrial setbacks: Vary by residential abutment.

Constructing within a required setback without an approved variance or waiver is a zoning code violation under Chapter 24, enforceable as a municipal infraction under Section 1-9; the city can deny or revoke a building permit and require the encroaching structure to be relocated or removed until the setback is met or relief is granted through the zoning variance process.

The Bottom Line

Gaithersburg's building setbacks & zoning rules are a mixed bag. Some areas are strict, others are relaxed, and the details matter. The best approach is to check the specific rule that applies to your situation rather than assuming Gaithersburg is broadly strict or permissive.

Keep in mind that Gaithersburg can amend these rules at any council meeting. For the most current version of any rule mentioned here, check the specific ordinance page, where we track updates as they happen.