ADU Contractors near Thornton, CO
LITTLETON, LLC
6698 South Iris Street, Littleton, CO 80162
23.9 miles
Littleton Construction, LLC is a Denver Metro general contractor since 1994, offering remodeling, additions, kitchens, basements & more. A+ BBB rated, licensed & insured, with 5-star reviews and a 1-year workmanship warranty.
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EcoMod
22303 Interstate 76 Frontage Road, Hudson, CO 80642
20.2 miles
EcoMod is a Denver-based ADU builder offering sustainable, affordable housing using repurposed shipping containers. Models range from 320–800 sq ft, starting at $64,000. Homes are 9x stronger, last 200+ years, and cut construction costs by 30%.
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A2Z Builders
501 South Lipan Street, Denver, CO 80223
15.1 miles
A2Z Builders is a Denver-based, family-owned Class A General Contractor with 16+ years of experience. They specialize in ADU construction, custom home builds, kitchen, bathroom, and basement remodeling across the Denver metro area.
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Sheffield Homes
6777 Wadsworth Boulevard, Arvada, CO 80003
9.4 miles
Sheffield Homes, founded in 1978, is a trusted Colorado custom home builder offering fully personalized builds since 2018. Services include basement finishing, luxury finishes, energy upgrades, and flexible floor plans, backed by decades of quality craftsmanship.
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ModernSpace ADU Construction Team Parker
10015 South Parker Road, Parker, CO 80134
27.4 miles
ModernSpace ADU Construction is a trusted ADU builder in Corona with 20+ years of experience. They offer detached ADUs, garage conversions, JADUs, attached additions, and full design services including permits and 3D renderings.
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3R Services
10825 West 32nd Avenue, Wheat Ridge, CO 80033
13.7 miles
3R Services builds ADUs in Arvada, CO, including backyard cottages, garage conversions & in-law suites. Projects cost $80K–$250K, take 3–6 months, and include permitting, transparent pricing & a 1-year warranty.
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Denver Custom ADU
10790 West 50th Avenue, Wheat Ridge, CO 80033
13 miles
Denver Custom ADU is a trusted ADU builder in Denver with 30+ years of experience. Led by Matt Brinn, they offer fixed pricing, monthly billing, proactive permitting, and commercial-grade standards for every residential ADU project.
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Denver Dream Builders
2339 East 5th Avenue, Denver, CO 80206
12.8 miles
Colorado general contractor since 2005, offering ADU builds, kitchen remodels, bathroom renovations, basement finishing, roofing, and new home construction. Free consultation, no upfront payment, licensed and insured.
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Murphey's Hammer LLC
Greenwood Village, CO 80112
21.7 miles
Murphey's Hammer is a Denver-based contractor specializing in ADUs, home additions, garage builds & outdoor living spaces. Serving Denver Metro, Aurora, Littleton & more with personalized, quality craftsmanship.
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Colorado Tiny Homes
200 S Wilcox St., #301, Castle Rock, CO 80104
38 miles
Colorado Tiny Homes builds luxury, eco-friendly ADUs across Denver, Castle Rock & the Rockies. Offering standard, mid-range & custom models, plus garage conversions. Free lot assessment included. Full permitting & project management handled.
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ADU Home Tour
6825 Eaton Street, Arvada, CO 80003
8.4 miles
L&D Construction is Denver's dedicated ADU contractor, led by Colorado native David Schultz. Specializing in accessory dwelling units, detached ADUs, and backyard cottages since 2017, they bring deep local expertise and firsthand ADU building experience to every project.
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Studio Shed
1500 Cherry Street, Louisville, CO 80027
10 miles
Studio Home is a Colorado-based prefab ADU builder serving all 50 states. With 18+ years experience and 6,000+ projects, they offer panelized ADU kits, backyard studios, granny flats, and in-law suites with fixed pricing and full project management.
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Jacques Family Construction
3500 Swanstone Drive, Fort Collins, CO 80525
43 miles
Jacques Family Construction is a licensed general contractor in Fort Collins, CO, offering custom home building, remodeling, basement finishing, home additions, and garage conversions, including JADUs, across Northern Colorado.
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Krick Design Build
759 1/2 Elati Street, Denver, CO 80204
13.5 miles
Krick Design + Build is a Colorado Front Range residential design-build firm specializing in ADUs. Founded by Licensed Architect Matthew Krick, they've completed 57+ ADUs including backyard cottages, garage conversions, and in-law suites.
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L&D Construction
5151 Bannock Street, Denver, CO 80216
9.4 miles
L&D Construction is a trusted ADU contractor and custom home builder led by owner David. Specializing in detached ADUs, granny flats, and full custom homes, they deliver quality craftsmanship, clear communication, and on-budget results.
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Other cities in Colorado
What you need to know
ADU Contractors in Thornton, Colorado: Building in One of the State's Fastest-Growing Cities
Thornton, Colorado, is one of the fastest-growing cities in the state and ranks among the top ten most populous cities in Colorado. This rapid population growth has driven significant demand for additional housing solutions, making Accessory Dwelling Units (ADUs) an increasingly popular option for homeowners. Whether you're looking to house extended family, generate rental income, or add long-term property value, working with experienced ADU contractors in Thornton, CO is essential to navigating the city's specific building requirements and maximizing your investment.
Thornton ADU Regulations and Zoning Requirements
Before breaking ground, homeowners must understand that Thornton operates under its own municipal zoning code, which governs where and how ADUs can be built. ADUs in Thornton are generally permitted in single-family residential zones, but they are subject to strict guidelines. Key regulations include:
- Size limitations: ADUs are typically capped at a percentage of the primary dwelling's square footage or an absolute maximum, ensuring the accessory unit remains subordinate to the main home.
- Owner-occupancy requirements: Thornton may require that the property owner reside in either the primary residence or the ADU.
- Setback and height restrictions: Detached ADUs must comply with rear and side yard setback rules specific to Thornton's zoning districts.
- Parking requirements: Additional off-street parking spaces may be required depending on the location and type of ADU.
- Utility connections: Separate utility metering may be required, and all connections must meet Thornton's municipal standards.
A qualified ADU contractor in Thornton will be familiar with the city's permitting process through the Thornton Community Development Department and can help ensure your project meets all local building codes and the International Residential Code (IRC) as adopted by Colorado.
Types of ADUs Built by Thornton Contractors
Experienced ADU contractors serving Thornton offer a range of construction options tailored to different lot sizes, budgets, and homeowner goals. Common ADU types include:
- Detached ADUs: Standalone structures built in the backyard, offering maximum privacy for both occupants.
- Attached ADUs: Units connected to the primary home, often sharing a wall but with a separate entrance.
- Garage conversions: Transforming an existing attached or detached garage into a livable space.
- Basement conversions: Finishing or converting an existing basement into a self-contained unit.
Why Hire a Local Thornton ADU Contractor?
Hiring a local ADU contractor in Thornton, Colorado offers distinct advantages. Local professionals understand the nuances of building in Adams County, are familiar with Thornton's permit timelines, and have established relationships with city inspectors. They also understand the regional climate — including Colorado's freeze-thaw cycles — which directly impacts foundation design, insulation requirements, and material selection. Choosing a contractor with proven Thornton experience ensures your ADU is built efficiently, compliantly, and to the highest standard.