Updated
Solar in Gaithersburg, MD is permitted by the City of Gaithersburg, not the county. Since February 2026 the city accepts standard residential rooftop solar and storage through SolarAPP+, an automated permit platform; it is optional, and homes in a historic district under a Historic Area Work Permit use the standard path.
Gaithersburg's own permit paths
The City of Gaithersburg launched SolarAPP+ for standard residential rooftop solar and energy storage in February 2026. The platform runs automated code checks against the 2021 International Residential Code and 2020 National Electrical Code, and the permit issues once the fee is paid.
Using it is optional. Standard applications still go through the city's online portal on standard review times, and homes in a historic district subject to a Historic Area Work Permit are not eligible for the automated path.
Sources: gaithersburgmd.gov
Why permits are getting faster across Maryland
A 2024 Maryland law requires all jurisdictions to adopt automated permitting software for residential rooftop solar and storage, which is why Gaithersburg and others now offer instant review. For batteries, that matters as much as for panels.
Gaithersburg homeowners can also look at Montgomery County Green Bank financing, which supports residential solar and storage.
Sources: pirg.org, mcgreenbank.org
Common Gaithersburg projects
Each page explains the work and the costs.
Gaithersburg solar questions
The City of Gaithersburg, not Montgomery County.
Yes. SolarAPP+ launched in February 2026 for standard residential rooftop solar and storage.
Not homes in a historic district subject to a Historic Area Work Permit.
Standard residential energy storage is included alongside rooftop solar.
Gaithersburg is in Montgomery County, so its Green Bank programs can apply.