Attached ADU in Pennsylvania

Ironstone Homes, Lancaster PA, specializes in ADU construction & multigenerational living spaces. Services include garage conversions, in-law suites, granny flats & backyard cottages. Custom builds with full permitting support since 2006.

Gauntlet Construction is a licensed ADU builder & design-build contractor in Roseville, CA. Serving Sacramento & Placer County, they offer ADU construction, garage conversions, home renovation & commercial builds with 15+ years of experience.

Willner Enterprises is a licensed Pennsylvania home improvement contractor (HIC# PA012219) serving the Pittsburgh area. They specialize in residential construction, remodeling, garage conversions, and ADU projects, with an active presence on Houzz and Yelp.

Hazley Builders is a family-owned design-build firm in West Chester, PA, serving Chester County since 1999. They offer custom homes, renovations, additions, and commercial construction with an integrated architect-led approach.

Lotus Restore & Remodel offers ADU design and construction in Montgomery County, PA. Services include garage conversions, basement renovations, in-law suites & backyard cottages. Licensed, family-owned, with 25+ years experience.

Cocoon Remodeling builds ADUs in West Chester & Philadelphia suburbs. From basement apartments to detached cottages & garage conversions, they handle design, permits & construction. Projects typically complete in 6–8 months.

Lake City Homes builds modular ADUs for multi-generational living, rental income, and more. Constructed indoors for quality control, these code-compliant units serve as backyard cottages, in-law suites, or guest spaces with 50+ years of building experience.

Oceanside ADU Design is an Oceanside, CA firm specializing in detached, attached, garage conversion, and junior ADUs. Founded by structural engineer Devin, they handle architecture, engineering, and permitting in-house for efficient, budget-conscious results.

Prime1 Builders constructed a custom ADU "Casita" in Gibsonia, PA for multi-generational living. The connected in-law suite features 2 bedrooms, open layout & full utilities. Winner of the 2023 House Excellence Award.

Lapp Structures builds ADUs (Accessory Dwelling Units), including detached garages with living quarters. A 3-car Gambrel garage ADU costs $50K–$60K. ADUs offer flexible living, rental income, and family housing solutions.

ADUs in Philadelphia offer rental income & flexible living space. Capped at 800 sq ft, they require owner occupancy & zoning compliance. Costs range $100–$300/sq ft. Matrix Design & Build manages design, permits & construction.