Prefab / Modular ADU

PCS Structures builds high-performance ADUs, backyard cottages & granny flats using SIPs technology. Their SHEDI line offers 15x more airtight construction, better energy efficiency, moisture control & faster build times than traditional m... read more

Fabmac Homes builds custom manufactured homes on Maui with 20+ years experience. Factory-built at Clayton Homes, shipped to Maui in 6–8 months. Features include hurricane-rated construction, energy efficiency, and permanent foundations. Ideal fo... read more

West Coast Homes, a Lynden, WA tiny home builder, specializes in accessory dwelling units (ADUs) like backyard cottages and in-law suites. They offer IRC-compliant plans, custom designs, and permitting guidance for Pacific Northwest homeowners see... read more

Monarch Architecture in Columbia, MO specializes in ADU design. Founder Adrienne Stolwyk advocated for ADU-friendly zoning via ECHO. In 2023, they built Columbia's first permitted straw bale ADU. Services include backyard cottages, in-law suites, ... read more

Urban ADU builds energy-efficient accessory dwelling units in Colorado Springs, CO. Featuring spray foam insulation, solar options, Zero Energy Ready certification, and 3D planning tools, they simplify ADU construction from permits to placement.read more

Pro's Edge Small Homes is a licensed ADU contractor in MA & NH with 20+ years experience. They offer turnkey design, permitting & modular construction of granny flats, in-law suites & backyard cottages, including a free property evalua... read more

CCPP helps homeowners plan & permit ADUs in San Luis Obispo County. Options include custom, stock plan, or manufactured units. Permitting takes 4–12 months, with costs ranging from $40K–$70K depending on ADU type.

New England Outdoor, a family-owned business in Methuen, MA, builds custom sheds, garages, pavilions, and ADUs across New England. Specializing in ADU construction, garage conversions, and in-law suites, they handle design, permits, and zoning gui... read more

Boston Deck Builders offers ADU construction in Greater Boston, including detached, attached, and interior units. Services cover planning, permitting, and build. Costs range from $150K–$400K+. Prefab options available. Compliant with Massachuset... read more

Spectrum Builds offers customizable ADUs for rental income, in-law suites, guest houses, and home offices. Their Summit Series prefab ADU adapts to evolving needs. Use their 3D Design Center to plan and price your accessory dwelling unit today.read more

prefabADU is a Bay Area ADU builder with 16+ years of experience offering affordable kits and plans from under $45K. With 12 state-approved plans valid across California, they simplify permits, design, and installation for homeowners.

Greenpod Design builds custom DADUs in Washington using SIP construction and sustainable materials. They handle permits, ADA-compliant design, and energy-efficient builds. WA law allows up to two ADUs per lot, up to 1,000 sq ft.

ADU Geeks is a full-service ADU builder offering planning, design, permitting, and build support. They also provide an online ADU Development Masterclass for $150, covering feasibility, construction, and financing across 40 videos.

TinyMod® offers turnkey ADU solutions in Omaha, NE, including custom plans, prefab & site-built construction. Designs range from studios to 2-bedroom units, built for local zoning compliance, affordability, and energy efficiency.

Top-Pro Construction, Inc. is Greater Boston's trusted ADU builder with 25 years of experience. Specializing in detached ADUs, attached units, garage conversions & basement ADUs to boost property value and rental income.