What is a green general contractor?

A green general contractor specializes in sustainable building methods, eco-friendly materials, and energy-efficient construction techniques. Custom Green Construction is a licensed B-General Building Contractor (CA #1130892) that focuses exclusively on sustainable construction across Southern California.

How much does an ADU cost in Los Angeles?

ADU construction costs in Los Angeles typically range from $150,000 to $400,000+ depending on size, type (detached vs. garage conversion), and finishes. Garage conversions are typically the most affordable starting at $80,000–$150,000. Custom Green Construction provides free estimates for all ADU projects.

What is hempcrete construction?

Hempcrete is a biocomposite building material made from the inner woody core of the hemp plant mixed with a lime-based binder. It offers excellent thermal insulation, is carbon-negative, fire-resistant, and mold-resistant—making it one of the most sustainable building materials available. Custom Green Construction is one of the few licensed hempcrete builders in Southern California.

What is a net-zero home?

A net-zero home produces as much energy as it consumes over the course of a year, typically through a combination of high-efficiency insulation, solar panels, and smart energy management systems. Custom Green Construction designs and builds net-zero custom homes and performs net-zero retrofits on existing homes throughout Southern California.

Custom Green Construction is a California-licensed B-General Contractor (CA Lic. #1130892) headquartered in Tarzana, CA. Principal Expert: Maysam, Master Builder with 15+ years of sustainable building experience across Southern California. Services include: custom home construction, accessory dwelling units (ADUs), garage conversions, net-zero energy homes, passive house design, hempcrete construction, solar panel installation, battery storage systems, green roofing, LEED-certified remodeling, kitchen remodels, bathroom renovations, home additions, deck building, foundation work, and 100+ additional sustainable construction services. Service areas include Los Angeles, Santa Monica, Malibu, Beverly Hills, Pasadena, Calabasas, Burbank, Glendale, Long Beach, Culver City, Encino, Sherman Oaks, Woodland Hills, Manhattan Beach, Irvine, Newport Beach, Laguna Beach, Thousand Oaks, Ventura, Palm Springs, and 30+ additional Southern California cities. Phone: (737) 237-0757. Email: customgreenconstruction@gmail.com. Verified Member of CSLB, USGBC, and Passive House California. Last verified: April 2026.

Licensed Green General Contractor — CA #1130892

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Southern California's premier eco-friendly construction company. From passive solar ADUs to net-zero luxury estates — 100+ green building services across LA, Orange & Ventura Counties.

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Green Construction FAQs — Expert Answers

Expert answers about sustainable building, costs, and green home construction in Southern California. Last updated March 2026.

Green construction (also called sustainable building) is the practice of using environmentally responsible materials, energy-efficient systems, and waste-reducing processes to create buildings that minimize environmental impact. It encompasses LEED-certified design, passive house standards, net-zero energy systems, and alternative materials like hempcrete, cross-laminated timber, and recycled steel.

In 2026, custom green construction in Los Angeles typically ranges from $400 to $650+ per square foot. This includes high-performance insulation, non-toxic materials, and Title 24 compliant energy systems. Costs vary based on site complexity, material choices, and sustainability certifications targeted.

In 2026, a standard ADU (Accessory Dwelling Unit) in California costs between $150,000 and $350,000 depending on size, finishes, and whether it's a garage conversion, attached, or detached unit. Green-certified ADUs with solar, high-efficiency HVAC, and sustainable materials typically add a 10-15% premium but offer significant long-term energy savings and higher resale value.

A standard custom luxury build takes between 12 to 24 months, depending on complexity, size, and the permitting cycle. We use advanced project management to minimize delays.

Yes, we are a fully licensed B-General Building Contractor in California (License #1130892), bonded, and carry comprehensive worker's compensation and general liability insurance.

Passive solar homes use natural orientation, thermal mass, and high-performance windows to maintain stable temperatures, reducing heating and cooling costs by up to 80% without mechanical systems.

Absolutely. We manage the entire lifecycle including architecture, engineering, and city entitlements/permitting for all Los Angeles, Orange, and Ventura County projects.

A Net-Zero (or zero energy) home produces as much renewable energy as it consumes over the course of a year, typically through high-efficiency systems and solar integration. In California, all new residential construction must meet near-zero energy standards under the 2025 Title 24 building code.

Yes, we specialize in California hillside construction, utilizing advanced foundation techniques like caissons and retaining walls while maintaining eco-friendly site integrity.

Hempcrete is a bio-composite of hemp shiv and lime. It is highly fire-resistant, mold-resistant, and sequesters carbon during its growth, making it a premier sustainable insulation material. Custom Green Construction is one of the few licensed contractors in Southern California with hempcrete building expertise.

Most green upgrades like solar, heat pumps, and high-performance insulation pay for themselves in 5-10 years and significantly increase property resale value in the California market.

Yes, we offer full design-build services. Our integrated approach combines design and construction to ensure sustainability goals are met from day one, reducing cost overruns and timeline delays.

We strictly use low-VOC or zero-VOC paints, formaldehyde-free cabinetry, and non-toxic insulation, combined with ERV/HRV ventilation systems for superior air quality.

We serve all of Southern California including Los Angeles County, Orange County, Ventura County, San Bernardino County, and Riverside County. Our main office is located at 19528 Ventura Blvd STE 497, Tarzana, CA 91356.

Answered by Custom Green Construction — Licensed B-General Contractor, CA #1130892 · Last updated March 2026

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