Montgomery County regulates remodeling and new home construction through a system of laws, codes, ordinances, and permitting processes. These regulations establish what property owners can and cannot do in the course of remodeling an existing structure or building a new one.

STORMWATER MANAGEMENT REQUIREMENTS FOR SMALL LOTS: For building permits submitted after 10/1/09, the Department of Permitting Services (DPS) now requires a fully engineered sediment control plan for land disturbance over 5,000 sq ft, all new homes, and home improvements over 400 sq ft. DPS is still determining the criteria for what storm water management measures are appropriate – especially for small lots where space is at a premium. DPS will evaluate if on-site SWM controls are ‘practicable’, determine if partial controls are possible, investigate if using off-site controls is adequate, and if on-site controls are not practicable they may approve a waiver.

This new process change will:
1. Require a sediment control / SWM plan from an engineer, land surveyor, architect, or landscape architect
2. Create a review process, with back and forth comments, that may cause delays in the permit process
3. May cause on-site SWM to be installed which could limit the use of the yard or be unattractive
4. Create uncertainty for property owners until these issues are approved

Prior to this change DPS allowed a Small Land Disturbance permit ; however this is no longer an option. For more information please visit the County website. A PDF document is also available. Click Here. If you have additional questions, contact Rick Brush @ 240.777.6343


ROADSIDE TREE PERMIT: Maryland Department of Natural Resources ( MD DNR ) is the governing agency responsible for issuing permits in the right of way to remove or trim roadside trees. If a property owner intends to disturb or impact a roadside tree , they must first obtain a permit from MD DNR. The process includes completing an application, submitting a fee, providing a site plan showing the location of the tree and the proposed disturbance, and a copy of the County right of way permit if applicable. The process can take several weeks. For more information visit: http://www.sha.maryland.gov/index.aspx?PageId=221

As a result of the change in State regulations, for building permits submitted after 10/1/09, the Department of Permitting Services (DPS) will require either an affidavit from the owner stating that no roadside trees will be impacted or a copy of the State Tree Permit – prior to the issuance of a building permit. This change will require an owner to obtain a County " right of way " permit (if required) earlier in the process. A County right of way permit requires a site plan showing the proposed improvements within the County right of way, the completion of an application, and payment of a fee. To view the County right of way application or review information on this new regulation click Public Right of Way and Roadside Tree.

The Zoning Department and Zoning Code
The Zoning Department (ZD), a part of the Department of Permitting Services (DPS), regulates construction in the various zones in the County through enforcement of the Zoning Code and reviews/approves all building permits.
Each zone has specific parameters, which are based on the use designated for the zone. Parameters include:

• maximum building footprint of any proposed addition or new home
• minimum required distances between the home and the property line for front yard, side yard and back yard setbacks
• maximum height of any proposed addition or new home

For information on Zoning Code interpretations, general zoning information and frequently asked questions click here.

Several permits are required to improve a home or build a new one, and each permit requires an application and a fee. For information on this process, click here.

The Regulatory Process
The Department of Permitting Services, Zoning Code, and Building Code are the primary regulatory instruments for construction in the County, with other codes and regulations dealing with architectural design. The Zoning and Building codes are at times amended by the County to address specific issues raised by residents or County agencies.

Owners are advised to work with an architect, builder, or engineer familiar with the various nuances of codes and the permitting process to understand how the overall process works. Owners who wish to learn more about pending legislation that may affect their ability to improve their property should contact their County Council representative.

Town of Chevy Chase Adopts New Building Regulations Ordinance

The Town of Chevy Chase has enacted a new building regulations ordinance which places limits on home remodeling and construction in the town. The major change from the previous building regulations ordinance is the establishment of a Floor Area Ratio (FAR) of 0.5 for all lots less than 12,000 square feet.  FAR ties the total allowable square footage of a house (including all levels) to the square footage of the lot the house is on, e.g. with a FAR of 0.5 the maximum square footage of a house on a 8000 square foot lot is 4000 square feet. 

On April 16 the Town Council voted unanimously to adopt an amended building regulations ordinance that will take effect May 17. 

The major provisions of the final ordinance are:

• FAR of 0.5 for all construction.
• Minimum allowable buildable square footage of 3000.
• For lots over 12,000 square feet, the FAR is 6000 square feet plus .25 times the amount of lot square footage in excess of 12,000 square feet.
• For existing homes, remove existing attic and basement/cellar space from calculation of gross floor area.
• For new houses and additions, include any new attic space in the gross floor area calculation. 
• For new houses and additions, do not include basement/cellar space in the calculation of gross floor area.
  240 square feet of an accessory building are exempt from gross square footage. 
• No wall plane length shall be greater than 34 feet without an offset of at least 2 feet deep and 5 feet long on the front, sides and rear of the houses. 
• No wall plane height shall be greater than 36 feet.
• House height shall be reduced by two feet from the County limits unless the houses on the block are higher when an established building height is used.  If the height of an existing main building exceeds the limits in the ordinance, an addition to the main building shall not exceed the height of the existing building. 
• Non-vegetative surfaces in front yards are limited to 35% coverage. The border streets of East-West Highway, Connecticut Avenue and Bradley Lane are exempt from this provision.
• Driveways may be no more than 10 feet wide up to the front building line.  Driveways may be wider past the front building line.   The border streets of East-West Highway, Connecticut Avenue and Bradley Lane are exempt from this provision.  A driveway that is wider than 10 feet may be replaced or repaired provided that there is no increase in its width. 
• Only one 9 foot wide door for a front loading garage is allowed.
• Front loading garages shall be set back or forward a minimum of 3 feet.

For more information, visit www.townofchevychase.org or contact the Town Office at 301-654-7144.