Although it is rare for this team to endorse specific providers, we’ve made a few thoughtful exceptions. The following companies are included because our local team has worked with them directly or they came highly recommended by trusted partners in the Washington DC, Maryland, and Northern Virginia ADU community. Each resource has demonstrated reliability, professionalism, and expertise in its respective field.

1. Capital ADU

Website: https://capital-adu.com
Expertise: Building, Design, Architecture, Zoning, Permitting
Locations Served: Washington DC, Maryland, Virginia

Capital ADU is a full-service ADU design-build company specializing in backyard cottages, garage conversions, and basement ADUs. They handle everything from zoning feasibility to architectural plans, permits, and full construction.

2. Ileana Schinder Architecture

Website: https://ileanaschinder.com
Expertise: Architecture
Locations Served: Washington DC, Maryland, Virginia

Ileana Schinder is one of the most recognized ADU architects in the region. Her firm has extensive experience designing elegant, efficient ADUs tailored to urban lots across DC and the surrounding suburbs.

3. Omega Property Group

Website: https://www.omegaregroup.com
Expertise: Historic Buildings, Design, Architecture, Zoning, Permitting
Locations Served: Washington DC, Maryland, Virginia

Omega Property Group specializes in historic properties, adaptive reuse, and complex zoning/permitting environments. Their team has notable experience navigating DC’s and MD's historic districts and challenging urban lots.

4. NW2 Engineers

Website: https://nw2eng.com
Expertise: MEP Design (Mechanical, Electrical, Plumbing)
Locations Served: Washington DC, Maryland, Virginia

NW2 Engineers provides high-quality MEP engineering services for ADUs and residential projects. They are known for efficient system design, energy-code compliance, and clear coordination with architects and builders.