Room Additions in Greater Los Angeles & the Bay Area

Room Addition in Greater Los Angeles & the Bay Area

A room addition adds living space without the cost and disruption of moving. Whether you need a master suite, a second bedroom, a home office, a family room, or a second story, EC Construction Group designs and builds additions that look and feel like they were always part of your home. In the Bay Area, we build additions in San Ramon, Walnut Creek, Concord, Martinez, Oakland and surrounding cities.

We serve Woodland Hills, Hidden Hills, Calabasas, Encino, Glendale, Santa Clarita, Thousand Oaks, and the full LA Metro Area. Every project includes structural engineering, permits, framing, insulation, drywall, electrical, HVAC tie-in, flooring, and final finishes.

Our CSLB-licensed team handles all permits and city inspections. We provide a written, all-inclusive price before construction begins; any change in scope is approved by you in writing first.

How much does a room addition cost in Los Angeles?

Cost depends on the size of the addition, foundation and structural work, how it ties into the existing roof and utilities, and the finishes. We don't quote numbers before seeing the project: after reviewing the space we give you a free, written, itemized estimate.

How long does a room addition take?

Most room additions take 2–4 months from permit approval to completion. Larger second-story additions may take 4–6 months.

What is the difference between a room addition and an ADU?

A room addition is attached to and part of the main home. An ADU (Accessory Dwelling Unit) is a separate or semi-separate living unit, often used for rental income or multi-generational living.

Do I need permits for a room addition in Los Angeles?

Yes. Most room additions require permits, plan review, and inspections. EC Construction Group handles the permitting process and coordinates all required approvals.

Can I live in my home during a room addition project?

In most cases, homeowners can remain in the home during construction. We carefully plan the project to minimize disruption and maintain safety throughout the process.

Will a room addition increase my home's value?

A professionally built room addition can significantly increase both usable living space and overall property value, making it one of the most popular home improvement investments.

What types of room additions do you build?

We build bedrooms, family rooms, home offices, guest suites, second-story additions, and other custom living space expansions tailored to your needs.

Can the new addition match my existing home?

Yes. Our team designs room additions to blend seamlessly with the home's existing architecture, roofline, exterior finishes, and interior layout.

Are you a licensed contractor?

Yes. EC Construction Group is a California licensed contractor (CSLB #1132619) for residential construction and room addition projects. You can check the license status, bond and workers' compensation details on the CSLB website, cslb.ca.gov.

How do I get started with a room addition project?

The process begins with a consultation where we discuss your goals, evaluate your property, review design options, and prepare a detailed project proposal.