Room Additions · Los Angeles
More space without moving. One team designs, permits, and builds your ground-floor addition, primary suite, or second story. Fixed price in writing before we start.
Why Add On
In Los Angeles, moving up usually means paying today’s prices and today’s interest rates for somebody else’s house. Adding on lets you keep your street, your schools, and your mortgage, and put the money into rooms built exactly the way you want them.
Athenian Builders Group is a licensed and insured California contractor (CSLB #1045030) that handles the whole addition: design, structural engineering, permits through LADBS or your city’s building department, and construction with our own crews. You get one point of contact, a fixed itemized price approved before we start, and a written 2-year workmanship warranty.
What We Build
A new bedroom, family room, or office off the back or side of the house, with the roofline and finishes matched so it never reads as an add-on.
A real primary suite: bedroom, walk-in closet, and a full bath of its own. The addition that changes how the whole house lives.
When the lot is tight, we build up: engineered framing, new stairs, and bedrooms with views instead of a smaller yard.
Sometimes the answer is a few hundred square feet in exactly the right place: we push the kitchen or living area out toward the yard and open it up.
Want a separate unit instead of connected space? A backyard ADU can add livable square footage plus rental income.
Transparent Pricing
Real 2026 ranges for LA additions. Structural scope, foundations, and finishes move the number, and your home’s condition matters as much as the size.
| Addition Type | Typical Size | Typical Cost (2026) | Typical Timeline |
|---|---|---|---|
| Ground-Floor Addition | 300–500 sq ft | $150k – $300k | 3–5 months |
| Primary Suite Addition | 400–600 sq ft | $200k – $380k | 4–6 months |
| Second-Story Addition | 500–900 sq ft | $300k – $700k+ | 6–10+ months |
Typical Los Angeles ranges for 2026, not quotes. Every addition starts with a free on-site walkthrough and a fixed, itemized price in writing. Financing is available for qualified homeowners: see remodel financing options.
Estimated project cost
Permits
Every addition in Los Angeles needs permits: structural plans, energy (Title 24) compliance, and plan check before a shovel touches dirt. That is not a problem, it is the process, and it is our job. We prepare the drawings, run the engineering, pull the permits, and manage every inspection through final sign-off.
Questions
Permitted, well-built square footage is one of the most direct ways to raise a Los Angeles home’s value, especially bedrooms and primary suites. The key word is permitted: unpermitted space does not count in an appraisal.
If you want connected living space, build an addition. If you want rental income or independent space for family, an ADU usually wins. We build both, and the free on-site visit is where we help you compare the numbers for your lot.
Ground-floor additions typically run 3 to 5 months of construction. Second stories run longer. Design, engineering, and permitting add time before that. You get a firm timeline in writing before we start.
Usually yes for ground-floor additions. Until the final tie-in, most of the work happens outside your existing walls. Second stories are harder to live under, and we will tell you straight whether staying home makes sense for your family.
Yes. We prepare the structural engineering, handle Title 24 energy compliance, run plan check, and manage every inspection, start to finish.
Get a free on-site feasibility visit and a fixed, itemized price for your Los Angeles room addition. Call (310) 857-2520 and you’ll know exactly what it costs before we ever break ground.
Free Addition Estimate
A fixed price and firm timeline, in writing. Same-business-day reply.
Takes about a minute. We reply the same business day and set up a free on-site visit.
