Renovation permits in Montgomery County, Maryland

What needs a permit

DPS says a permit is required before reconstructing or renovating an existing structure, other than a repair. Its home improvements page lists work that likely needs a permit:

• Additions, decks, garages, sheds, fences, and retaining walls
• Interior alterations and electrical work
• Replacing HVAC heating equipment
• Exterior work on a historic property
• Land disturbance over 5,000 square feet or 100 cubic yards

The same page says cabinets, floor coverings, gutters, siding, roof covering only, patios, and windows or doors in the same-size opening most likely do not need a permit. Plumbing permits come from WSSC, not DPS. Some incorporated towns and cities in the county have their own requirements, so check with your municipality too.

Residential Fast Track

DPS's Residential Fast Track is for smaller residential projects, such as some kitchen and bath remodels, basement finishing, and single-level decks. Applications are filed electronically and, according to DPS, are generally issued in one to two business days. DPS's eligibility list (dated May 2021) limits kitchen and bath remodels to 400 square feet and basement finishing to basements without a kitchen, and excludes properties served by a private well or septic system. Confirm current eligibility with DPS before you apply.

Additions: the notice sign

An addition permit is required to extend the area, height, or footprint of a one- or two-family home. After the permit is issued, DPS requires a yellow notification sign posted within 3 business days and kept up for 30 days, within 5 feet of the front property line. Other inspections cannot go ahead until the sign is approved.

Historic sites and districts

DPS says a Historic Area Work Permit (HAWP) is required for substantive exterior changes to a historic site, including additions, replacing windows, doors, or porches, and demolition. Interior work and ordinary maintenance are exempt. The Historic Preservation Commission reviews HAWPs. A HAWP has no DPS fee, and it does not replace the building permit.

Applying and inspections

• Apply and pay through DPS's online services and upload plans to ePlans. A non-refundable filing fee is due at application.
• Request inspections at least 24 hours in advance, using the permit number and Contact ID printed on the permit.
• Questions go to MC311 (dial 311, or 240-777-0311 from outside the county). DPS is at 2425 Reedie Drive, 7th floor, Wheaton, and offers predesign consultations.

Homeowner permits and MHIC licensing

On the DPS podcast (Oct 2, 2025), DPS staff said homeowners file about 40 percent of alteration, addition, and deck permits as their own contractor, that the arrangement is meant for owner-occupied homes, and that anyone a homeowner hires for home improvement work must hold a Maryland Home Improvement Commission (MHIC) license. They also called a contractor asking the homeowner to pull the permit a warning sign.

Our guide to checking a contractor's MHIC license shows where to look one up. If you are planning a project in the county, start a project and we can talk it through.