A free site visit, a check of what your lot allows and a written, line-item price.
Get your free estimateFast, Reliable Home Addition Contractor Across Los Angeles
A room addition in Los Angeles typically runs $180 – $420 per square foot, with a full sunroom addition landing between $65,000 and $145,000 depending on the existing slab, electrical panel, and waterproofing condition. Most pre-1979 homes in Los Angeles trigger code upgrades once walls are opened, so budget for rewiring, shear wall retrofits, or slab replacement before the first nail goes in. We’re Lodgewick ADU Los Angeles, part of the Kingswell family of home-service companies, and we run every project under The Kingswell Guarantee: a written price before work starts, a real arrival window, a clean job site, and a written guarantee on every job. Call (213) 698-7116 and a live person answers, day or night.
Why Lodgewick ADU Los Angeles Is Los Angeles’s Preferred Home Addition Contractor Company
Los Angeles homeowners have been burned before. They’ve seen prices change at the door, crews that never showed, and work that failed a month later. We started in 2010 as the ADU company of the Kingswell family. Since then, we’ve built a reputation in Los Angeles for putting every commitment in writing before any work begins. Our Home Addition Contractor team operates differently because The Kingswell Guarantee demands it: written price first, defined arrival window, written guarantee on every project, and a free return visit if the work fails within the 365-day period.
Every technician who steps onto your Los Angeles property is background-checked and uniformed, so you always know who’s there. Our Los Angeles office coordinates dispatch and scheduling locally; crews know how to route through the 10, the 110, and the 405 to reach Lawndale, Culver City, Manhattan Beach, Venice, and every neighborhood in between. When you call with a question about your build or your guarantee, a live person answers. No voicemail loops. No chatbots. Russ Delmar leads our Los Angeles team, and he’s the one who reviews every written change order before it reaches your signature.
Sunroom Addition in Los Angeles
A Sunroom Addition in Los Angeles is one of the most cost-efficient ways to add livable square footage to a lot that’s already built out, especially on those long, narrow single-family parcels that dominate neighborhoods from Leimert Park to El Sereno. Because Los Angeles gets roughly 284 sunny days a year and very little rain, a well-built sunroom becomes usable living space almost year-round. Here’s what you should know before you build.
Foundation and Existing Slab Reality
Many homeowners assume a sunroom can sit on the existing patio slab. That’s rarely true in Los Angeles. Most original slabs under older homes are 2 to 3 inches thick, porous, and unreinforced. Today’s code requires a 4-inch reinforced slab with proper drainage. Budget for slab replacement or a new foundation pad, typically $8,000 – $18,000 depending on access and soil condition.
Weatherproofing the Transition
The point where the sunroom meets the existing house is where Los Angeles sunrooms fail most often. Our crews flash and seal that transition with the same standard we use on full additions: integrated waterproofing membrane, properly lapped flashing, and a weep system where the roofs meet. The rare heavy rain Los Angeles gets, like the atmospheric river events we’ve seen in recent winters, will find any crack in a rushed transition. We price and build it so it won’t.
Room Addition Contractor in Los Angeles
Choosing a Room Addition Contractor in Los Angeles is different from choosing one in Phoenix or Austin. Our housing stock is old, dense, and built under codes that were far more relaxed than what a permit triggers today. When you open up a pre-1979 Los Angeles home, you’re not just adding square footage. You’re triggering a chain of code upgrades: knob-and-tube rewiring, undersized 60-amp panels, missing shear wall bracing, and original concrete pads too thin for current requirements. Our job is to find those before demolition day and put the real number in writing.
Inspection Before Estimate
We walk the lot, check the existing panel, probe the slab, and look at the framing before we give you a written price. That inspection finds most of what a permit will flag. If something is hidden behind a wall and only shows up during construction, we write a change order with an exact price, get your signature, then proceed. The price never moves without your approval in writing. That’s The Kingswell Way.
The West Adams Garage Conversion
On a garage conversion in West Adams, our crew pulled back the original 1920s concrete pad and found it only 2 inches thick, well under today’s 4-inch reinforced slab requirement. We wrote a change order for full slab replacement, got the homeowner’s sign-off before demolition, and brought in a pump truck the same week so the project stayed on schedule. The new James Hardie siding went up over properly flashed shear walls, and the final inspection passed without a single correction.
Trusted Brands We Service in Los Angeles
Lodgewick ADU Los Angeles works hands-on with leading ADU brands and materials, including James Hardie siding, Abodu prefab units, and Cover modular systems. That means when we price your Los Angeles addition, we can match the right product to your lot, your timeline, and your budget without guessing. Because our crews install these systems regularly, turnaround on parts and materials is fast for Los Angeles customers. We’re not waiting on a specialty order we’ve never seen before. We stock and handle what we recommend.
Common Home Addition Contractor Problems We See in Los Angeles Homes
- Knob-and-tube wiring and 60-amp panels. Homes built before 1979 in Los Angeles often still carry original knob-and-tube circuits or undersized electrical panels. The moment a permit is pulled, those get flagged and must be replaced, which can add $8,000 – $25,000 to a project.
- Missing shear wall and hold-down hardware. Older stucco bungalows from the 1920s through the 1970s frequently lack the lateral bracing required once a second story or major room addition is added. Retrofitting shear walls and hold-downs is not optional; it’s what keeps the addition standing in an earthquake.
- Too-thin original concrete pads. In neighborhoods like West Adams and Highland Park, detached garages sit on original 1920s concrete that’s often 2 inches thick. Today’s code requires a 4-inch reinforced slab, so nearly every garage conversion needs full slab replacement before framing can start.
- Failed waterproofing at the old-to-new transition. Slapping a new addition onto existing framing without properly flashing and sealing the joint means the first heavy rain exposes leaks exactly where old meets new. Los Angeles gets most of its rain in a few intense storms, so a bad transition fails fast and visibly.
Pricing for Home Addition Contractor in Los Angeles, CA
Here are honest Los Angeles price ranges for the work we do most often. A room addition runs $180 – $420 per square foot depending on whether it’s a ground-floor bump-out, a second-story addition, or a garage conversion. A sunroom addition typically falls between $65,000 and $145,000. A bathroom addition runs $45,000 – $95,000. A garage addition or conversion runs $110,000 – $190,000. A second-story addition is the most expensive, typically $250,000 – $400,000, because it requires engineered shear walls, upgraded foundation connections, and a full roofing system. Bump-out additions that extend a kitchen or living room by 100 to 200 square feet run $40,000 – $85,000. These ranges include the code upgrades a Los Angeles permit triggers, because we build allowances into every written price. Call (213) 698-7116 for a free, line-item estimate. Written price, zero pressure.
We Also Serve Cities Near Los Angeles
Our Los Angeles crews work throughout the South Bay and Westside, including Lawndale, Culver City, Manhattan Beach, and Venice. If you’re in any of those cities, the same written-price guarantee and local permitting knowledge applies. Even if you’re outside Los Angeles proper, you’re still getting our Home Addition Contractor in Los Angeles team, which means the same crews and the same guarantee.
Serving Los Angeles, CA - Our Local Coverage Area
We’re based in the Los Angeles area and know this community well. Use the map below to see our service coverage - if you’re nearby, we can almost certainly help.
FAQs About Home Addition Contractor in Los Angeles
Opening walls on a pre-1979 Los Angeles home triggers upgrades to electrical (knob-and-tube replacement and panel upsizing to at least 100 amps, often 200), seismic bracing (shear wall and hold-down retrofits), and foundation work if the existing slab is under 4 inches thick. These typically add $15,000 – $45,000 depending on what’s behind the walls. We include allowances for these in our written price so you’re not surprised at rough-in inspection. Call (213) 698-7116 and we’ll walk the property before we quote.
Original garage slabs from the 1920s and 1930s in West Adams and similar neighborhoods were poured 2 to 3 inches thick with no reinforcement and no vapor barrier. Current Los Angeles code requires a 4-inch reinforced slab on compacted base, and an inspector will not sign off on framing over an old pad. Full slab replacement adds roughly $8,000 – $18,000 and about a week to the schedule. We flag this in the estimate stage so it’s in the written price, not a mid-project surprise.
State laws AB 68, AB 881, SB 9, and SB 13 eliminated most parking requirements, reduced setbacks to as little as 4 feet, and removed owner-occupancy mandates for ADUs on single-family lots in Los Angeles. That means a garage conversion or backyard addition that was illegal to build ten years ago may now be permitted by right. The same laws, however, require the existing structure to meet current structural and waterproofing code once it’s modified, which is why a conversion frequently costs more than the initial estimate from a drive-by quote.
We stop work, document what we found, and write a change order with the exact cost to correct it. You approve the number in writing before we proceed. Failed waterproofing at the old-to-new transition is common on Los Angeles homes because decades of expansion, contraction, and rare but intense rains have worked the original flashing loose. Ignoring it means the new addition leaks from the first storm. We price the fix, get your sign-off, and build it right.
If your Los Angeles property is on a hillside, in a liquefaction zone, or in an area with expansive clay soils (common in pockets of the San Fernando Valley and parts of the Hollywood Hills), the city may require a soils report before issuing a permit. That report runs $2,500 – $5,000 and dictates whether you need a deeper foundation, grade beams, or piers. We can order the report through our local geotechnical partners and factor the results into your written price before we dig. Call (213) 698-7116 to schedule your free estimate.
Key Takeaways for Los Angeles Homeowners:
- Room additions in Los Angeles run $180 – $420 per square foot; sunrooms run $65,000 – $145,000 total.
- Pre-1979 homes trigger code upgrades: rewiring, panel swaps, shear walls, and slab replacement.
- AB 68, AB 881, SB 9, and SB 13 removed parking, setback, and owner-occupancy rules, but also require stricter structural upgrades when walls are opened.
- We write allowances into every contract, and any hidden condition is priced and signed as a change order before we touch it.
- Every project carries The Kingswell Guarantee, including a written guarantee and free return visit if the work fails within 365 days.
If you’re planning a room addition, second-story addition, sunroom, bathroom addition, garage conversion, or bump-out in Los Angeles, call (213) 698-7116 for a free written estimate. We’ll walk the property, show you the numbers, and put everything in writing. No pressure. No surprises. Just straight answers.
Written by Russ Delmar, Owner at Lodgewick ADU Los Angeles, serving Los Angeles and surrounding South Bay and Westside communities since 2010.
