Montgomery County, MD Building Setbacks & Zoning: Lot Coverage Limits (2026)
Key Facts
- Max lot coverage
- 25% of lot (R-200 zone)
- Governing section
- Zoning Ordinance § 4.4.7.B
- Zone
- R-200 (20,000 SF minimum lot)
- Enforced by
- Dept. of Permitting Services
- Excluded municipalities
- Rockville, Gaithersburg, 5 other towns
Summary
The R-200 single-family zone limits total lot coverage to 25% of the lot under Montgomery County's Zoning Ordinance, covering principal buildings, garages, sheds, pools, and other accessory structures combined.
Section 4.4.7. Residential - 200 Zone (R-200) ... B. R-200 Zone, Standard Method Development Standards ... Coverage (max) Lot 25%
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-90: Montgomery County Code contains legislation effective through May 7, 2026 | Zoning Updated Effective: April 13, 2026 | COMCOR Regulations effective as of July 1, 2026).
Full Breakdown
Chapter 59, the Zoning Ordinance, sets development standards by zone. Section 4.4.7.B, the R-200 Zone Standard Method Development Standards table, lists the district's Coverage (max) standard for Lot at 25%, meaning the combined footprint of the principal building and all accessory structures on an R-200 lot cannot exceed a quarter of the lot area. The Department of Permitting Services enforces this cap through building-permit and site-plan review. The rule does not apply in Brookeville, Poolesville, Laytonsville, Rockville, Barnesville, Gaithersburg, or Washington Grove, which run their own zoning ordinances under Zoning Ordinance Section 1.3.2.
Violations & Fines
Building beyond the 25% coverage cap without a variance risks permit denial, a stop-work order from the Department of Permitting Services, or removal of the excess structure.
Frequently Asked Questions
Does the 25% lot coverage cap include my shed and pool deck?
Does this rule apply if I live in Rockville or Gaithersburg?
Sources & Official References
Other rules in Montgomery County
Compare Montgomery County to another location·View the Maryland building setbacks & zoning overview
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