Fast, Reliable Home Addition Contractor Across Altadena
Home additions in Altadena run between $180 and $420 per square foot depending on fire-zone requirements, site access, and whether you’re building ground-up on an Eaton Fire-cleared lot or adding onto an existing 1920s Craftsman or mid-century ranch. That’s the honest range we quote from, and we put the number in writing before any work starts. If you’re planning a sunroom, a second story, a garage conversion into living space, or a full room addition on your Altadena property, call (254) 602-5618 and we’ll walk the site, check the County requirements, and give you a fixed price. No door-knock surprises, no change orders because someone forgot the fire-zone cladding.
We know Altadena’s permit path is different from Pasadena’s or Arcadia’s, and that difference is exactly where out-of-town crews lose months and thousands of dollars. Our Home Addition Contractor team scopes every project against LA County Regional Planning and Building & Safety before we quote, so the number we hand you already includes the Chapter 7A vents, the Class A roof assembly, and the non-combustible siding the County will require in your Very High Fire Hazard Severity Zone.
Why Lodgewick ADU Builders Is Altadena’s Preferred Home Addition Contractor Company
Lodgewick ADU Builders has been building in Altadena since the Kingswell family founded the company in 2010, and our crews have worked parcels from the base of the San Gabriels near El Prieto Road down to the flatter streets west of Lake Avenue. Russ Delmar leads the team, and he’s the one who makes sure every Altadena project carries the 365-Day Done Right Promise in writing: if the work isn’t right within a year, we come back and make it right, free.
Altadena homeowners have told us the same story for years: a contractor quotes a number, shows up late, then hands over a change order because “the County wants fire-rated vents” or “the septic setback changed things.” Those are the things we check before we quote, not after we start. That’s the Kingswell Way: say the price before the work, show up in the window we gave you, leave the job site cleaner than we found it, and put the guarantee in writing.
Our live-person dispatch means when you call about your Altadena addition, a human answers, 24 hours a day. Not a voicemail, not a chatbot. That matters when you have a question about your permit status or a material delivery at 8pm.
Sunroom Addition in Altadena
A sunroom addition in Altadena typically costs $40,000 to $90,000 depending on the foundation work, glazing package, and whether the room needs to meet fire-zone glazing and ignition-resistant assembly standards under CA Building Code Chapter 7A. Most Altadena sunrooms we build are ground-up on previously improved lots, especially where the Eaton Fire cleared an existing structure, and that means full foundation, footing, and County inspection work, not just a prefab panel drop onto an old patio slab.
Altadena’s sun and mountain exposure mean the glazing choices aren’t cosmetic. South- and west-facing sunrooms up against the San Gabriels get brutal afternoon heat from May through October, so we spec low-E glass and, in the fire zone, require dual-pane tempered glazing that meets ember-intrusion standards the County plan-checker will specifically look for.
Fire-Zone Glass and Cladding
If your Altadena parcel sits in the Very High Fire Hazard Severity Zone, which most do, the County will require non-combustible cladding within the required setbacks, Class A roofing on the sunroom, and ember-resistant vents rather than standard screened soffit vents. We include these in the quote. A Pasadena-based crew quoting a “sunroom kit” price will not, and that’s the difference between a clean inspection and a stop-work order.
Slab vs. Raised Foundation on Altadena Lots
Older Altadena homes on raised foundations often can’t support a sunroom addition without a new independent foundation. On larger lots off Fair Oaks Avenue or Lincoln Avenue, we usually pour a new slab with proper drainage grading, which the County requires before we set footings. That grading plan is a line item we price up front, not a surprise later.
Room Addition Contractor in Altadena
Room additions in Altadena run from $70,000 for a simple bump-out bedroom or home office up to $200,000 or more for a full primary suite with bath, and the single biggest cost driver in this town is not square footage but the LA County permit path and the fire-zone assembly requirements that come with it. We’re a Room Addition Contractor that opens every Altadena scope by pulling the parcel’s County records, checking its fire-hazard designation, and verifying well and septic setbacks on acreage lots before we write a number.
That pre-quote verification is the only honest way to price a room addition here. On a recent West Altadena lot, we added a sunroom and a detached shop where the County required well and septic setback verification and a grading and drainage plan before we could set footings. That reshaped the scope before we quoted, not after demolition started.
Post-Eaton Fire Ground-Up Additions
Many Altadena room additions in 2025 and 2026 are being integrated into primary-residence reconstruction under the County’s expedited fire-rebuild pathways. That means your room addition may not be a separate permit at all; it may be folded into a rebuild package that requires a single plan-check submission, one set of structural calcs, and one inspection schedule. We coordinate that with LA County Building & Safety so your addition doesn’t stall the rebuild.
Acreage Lot Scoping Before We Quote
On larger Altadena parcels, especially east of Lake Avenue toward the foothills, well and septic setbacks rule the buildable area. We verify those setbacks before quoting, because adding a room that encroaches on a leach field or well radius triggers a civil-engineering plan and a price change that has nothing to do with lumber. We’d rather find that out in week one than in week twelve.
Trusted Brands We Service in Altadena
Lodgewick works hands-on with established ADU and addition building systems including Abodu, Cover, and Dvele, and we match the system to the lot. For Altadena parcels in the Very High Fire Hazard Severity Zone, we often spec James Hardie non-combustible cladding and Class A assemblies from ground-up. Because we stock and source these materials through our Los Angeles office and have them staged for Altadena delivery, we avoid the three-to-six-week supplier delays that stall smaller crews. When your addition or ADU goes through County plan-check, we already know which brand and assembly spec will pass the first review.
Common Home Addition Contractor Problems We See in Altadena Homes
- Pasadena permit assumptions. Crews that work Pasadena or Arcadia show up expecting a municipal counter with over-the-counter expedite. Altadena parcels go to LA County Regional Planning and Building & Safety, a different agency with different plan-check reviewers, different fee schedules, and no Pasadena-style counter expedite. We’ve seen a $12,000 change order triggered by exactly that mistake.
- Fire-zone upgrades skipped in the quote. Most of Altadena sits in a Very High Fire Hazard Severity Zone, which means Class A roofing assemblies, ember-resistant vents under CA Building Code Chapter 7A, and non-combustible exterior cladding within required setbacks. Quotes from flatland LA County crews routinely leave these out, then the plan-checker flags them, and the homeowner eats the resubmittal fee and the material upgrade.
- Acreage lots quoted like city lots. Septic and well setback verification, grading plans, and drainage requirements are common on Altadena’s larger parcels. A crew that doesn’t check those before quoting is setting you up for a change order the moment County plan-check requires civil work before footings.
- No written guarantee on the work. An addition is a five-figure investment on a home you already own. If a contractor won’t put the warranty in writing, walk. Our 365-Day Done Right Promise is written into every Altadena contract: if the work fails within a year, we come back and make it right.
Pricing for Home Addition Contractor in Altadena, CA
Here’s what we quote in Altadena: sunroom additions run $40,000 to $90,000. Room additions start around $70,000 for a simple bedroom or office bump-out and run past $200,000 for a full suite with bath and fire-zone cladding. Second-story additions typically start at $150,000, driven by structural work, stair integration, and fire-rated assembly. Detached ADUs run $180,000 to $350,000, and if you’re folding an addition into an Eaton Fire rebuild under the County’s expedited pathway, the addition’s share of that package often falls between $60,000 and $120,000 depending on scope. What moves the number: fire-zone material upgrades, septic and well setbacks, grading and drainage on open lots, and the plan-check route, which is County, not city, every time in Altadena. Call (254) 602-5618 for a free estimate; we’ll walk the parcel and put the real number in writing.
We Also Serve Cities Near Altadena
Our crews work throughout the San Gabriel foothills and the surrounding communities. If your property is in Pasadena, La Canada Flintridge, San Marino, or Sierra Madre, we bring the same written-price-before-work standard and the same 365-Day Done Right Promise. The permit path changes the moment you cross into Altadena, which is exactly why our Home Addition Contractor in Altadena team handles the County process directly, while our broader service area work follows each city’s municipal rules.
Serving Altadena, CA - Our Local Coverage Area
We’re based in the Altadena 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 Altadena
LA County Regional Planning and LA County Building & Safety issue every addition and ADU permit in Altadena, because Altadena is unincorporated Los Angeles County, not an incorporated city. There is no municipal planning counter and no over-the-counter expedite like Pasadena offers. We file with the County directly and manage the plan-check process for you. Call (254) 602-5618 and we’ll pull the parcel records and tell you exactly which County reviewer will see your plans.
Hundreds of Altadena parcels are now in the County’s expedited fire-rebuild pathway, which means additions and ADUs can be integrated into the primary-residence reconstruction under one consolidated permit package. That can save months versus separate plan-check cycles. If your lot was fire-cleared, your addition is likely ground-up construction on a previously improved parcel, which changes foundation scope, soil compaction, and the build sequence. We verify your parcel’s rebuild status before quoting.
Yes. Most Altadena parcels require Class A roofing assemblies, ember-resistant vents per CA Building Code Chapter 7A, and non-combustible exterior cladding within required setbacks. Those material upgrades typically add $15 to $35 per square foot compared to a flatland LA County build, and any quote that doesn’t include them will get flagged at plan-check. We include them on the first quote, not in a change order. For an exact number on your parcel, call (254) 602-5618.
We verify well and septic setbacks, grading and drainage requirements, and equipment access before we quote any Altadena acreage lot. On a large parcel off Fair Oaks Avenue near the base of the mountains, our crew scoped a detached ADU and shop addition where the County plan-checker flagged the original submittal for using the Pasadena permit path. Once we rerouted to LA County Regional Planning and Building & Safety, we rebuilt the package with James Hardie non-combustible cladding, Class A roofing, and Chapter 7A ember-resistant vents, then coordinated the long material haul and equipment access down a narrow private drive. Those checks happen before the price, not after.
Yes, we build detached shops, outbuildings, and ADUs together as one scope when the parcel allows it. On Altadena’s larger lots, the County will require the same fire-zone assemblies on the shop as on the dwelling, plus the same setback verifications. Combining them into one permit package saves plan-check fees and one inspection cycle. Tell us what you want the space to do, and we’ll tell you what the County will require and what it’ll cost. Estimates are free at (254) 602-5618.
Written by Russ Delmar, Owner at Lodgewick ADU Builders, building additions and ADUs in Altadena on the Kingswell Guarantee since 2010.