Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across North Hollywood
Home additions and ADU construction in North Hollywood typically run $45,000-$130,000 for room additions and $90,000-$220,000 for detached units, with permits and soft-story compliance adding complexity you won’t find in coastal LA markets. We’re Rowan Construction Group, and our crews work the San Fernando Valley basin regularly - dispatch and scheduling run from our Los Angeles office, but the trucks that roll to North Hollywood know the difference between a 1952 stucco bungalow off Lankershim and a 1960s dingbat near Magnolia. That local knowledge matters because the same square footage can encounter completely different structural realities depending on which postwar era built your walls. Call (213) 221-0788 to schedule your free estimate - we’ll put the number in writing before anyone picks up a tool.
Why Rowan Construction Group Sherman Oaks Is North Hollywood’s Preferred Home Additions & ADU Company
We’ve delivered over 4,000 projects since 2007, every one with a written price before work started and a documented photo record when the crew left. North Hollywood homeowners find us the same way they research appliances - they read the three-star reviews, they compare the line-item quotes, and they call because we name the price range on the page in dollars they can screenshot.
Our response time to North Hollywood is same-day for initial site visits, with crews already running between Studio City and Van Nuys on most days. The 365-Day Done Right Promise applies here exactly as it does everywhere we work: if it’s not done right, we make it right - backed by The Haven Standard, not a handshake. Background-checked, uniformed technicians; a live person answering calls 24/7; and that documented photo record on every visit, included as standard.
What separates us in this market is our familiarity with the Northridge earthquake legacy. North Hollywood sits just a few miles from the 1994 epicenter, and the concentration of 1950s-1970s soft-story construction here is unlike anything in Burbank or Glendale. Our Home Additions & ADU team has navigated Ordinance 183893 retrofit triggers on enough projects that we build the possibility into our initial scope - not as a surprise, but as a line item you can evaluate upfront.
Our Home Additions & ADU Services in North Hollywood

ADU Design & Permitting
North Hollywood’s ADU pipeline runs through LA Department of Building and Safety with additional scrutiny for any project touching a soft-story footprint. We handle the full design-permit-build sequence, including the preliminary structural assessment that tells you whether your 1950s foundation and framing will carry the load. A typical detached ADU in North Hollywood runs $90,000-$220,000, and we won’t start without a written scope, a written price, and a signed agreement. Under Clause 1 of the Haven Standard, that price is fixed - no change proceeds without a signed change order.

Garage Conversion ADU
Converting a garage in North Hollywood sounds straightforward until you open the walls. Many original garages share a foundation with the main house, lack shear walls, and sit on slabs poured without the reinforcement an occupied unit now requires. We price garage conversions at $30,000-$80,000, but the real variable is what the existing structure demands. Our crew opened a 1952 stucco bungalow near Lankershim Blvd and Magnolia for a 400 sq ft addition, and the original 2×4 framing was undersized and termite-damaged with no shear walls - we stopped work, added the shear panel and hold-downs to the scope of work, and priced it in writing as a change order before scheduling inspection sign-off, finishing the rough-in on budget for a home addition in the $45,000-$130,000 range.

New Detached ADU
Detached ADUs in North Hollywood face the same heat-load challenges as the main house - 108-113°F summer days in the interior San Fernando Valley basin force HVAC sizing that would be over-engineered west of the 405. We specify higher-rated roofing underlayments and schedule concrete pours before 7 a.m. to beat the thermal stress. The Haven Standard requires we document every pour, every inspection, every material delivery with photos you receive automatically - not as an upgrade, but as the baseline record of what happened on your property.

Junior ADU & Interior Conversion
Junior ADUs, or JADUs, convert existing interior space - typically a bedroom or attached garage - into a self-contained unit with a kitchenette and separate entrance. In North Hollywood’s post-WWII bungalows, these conversions often trigger the same code upgrades as larger projects: electrical panels upgraded from 60-amp service, original galvanized plumbing replaced, and fire separation between units. We scope these explicitly in the written quote, with allowances for the conditions we can’t see until walls open.

Room Additions & Second Story Additions
Room additions and second-story work represent our largest project category in North Hollywood. The $45,000-$130,000 range covers everything from a 200 sq ft rear extension to a full second-story pop-up, but the critical factor is the existing structure’s capacity. A North Hollywood addition opened for permits triggers a mandatory soft-story retrofit review if the original 1950s tuck-under carport is being converted or altered - a sequence that rarely applies in neighboring Burbank or Glendale because their pre-1978 dingbat inventory is smaller and their retrofit ordinances differ. We build this possibility into our permitting timeline and our contract allowances so you’re not financing a surprise mid-project.

What happens when you call
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A real person answersNo phone trees - you reach a local pro.
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You get an upfront price rangeHonest numbers before anyone is dispatched.
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A background-checked tech heads outLicensed & insured, dispatched right away.
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You approve before work beginsNothing starts until you say go.
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AfterTrusted Brands We Service in North Hollywood
Our sourcing runs across fifty-plus vetted brands - KraftMaid and Wellborn cabinets, Cambria and Caesarstone countertops, GAF and Owens Corning roofing, Kohler and Toto fixtures, Belgard and Techo-Bloc pavers - which means the written quote carries honest numbers rather than inflated ones. For North Hollywood’s heat-stressed roofs, we regularly specify IKO and Atlas underlayments rated for the thermal cycling the San Fernando Valley demands; Tamko and Boral products figure into our standard material lists where the project calls for them. We stock common items locally to avoid the lead times that stretch Valley projects, and every brand name in your quote is one we can show you in a sample before you sign.
Common Home Additions & ADU Problems We See in North Hollywood Homes

- Undersized or termite-damaged framing in 1950s bungalows. The original 2×4 studs and rafters often can’t carry modern loads, and decades of valley moisture have invited pests. We find this on initial inspection about half the time near Magnolia and Lankershim - we price the upgrade in writing before demolition starts.
- Missing seismic hardware from the pre-Northridge era. Foundation bolts, shear panels, and hold-downs weren’t required when most of North Hollywood’s housing stock went up. Opening walls for an addition exposes the gap, and the city inspector will notice. Our contracts include a seismic allowance we can activate with a signed change order, not a verbal “we’ll figure it out.”
- Original electrical and plumbing at end-of-life. Knob-and-tube remnants, 60-amp panels, and galvanized supply lines are routine in 1945-1965 construction. We test and photograph what’s visible, write an allowance for what’s likely, and stop work to re-scope if we find worse.
- Soft-story retrofit triggers under Ordinance 183893. Any project that touches a tuck-under carport or alters a soft-story footprint can activate mandatory retrofit compliance - sequenced shoring, phased permitting, weeks of additional work that flat square-footage estimates from out-of-area contractors simply omit. We’ve done enough of these to know the real cost.
Pricing for Home Additions & ADU in North Hollywood, CA
Here are the numbers we put in writing before any work starts:
| Service | Typical Range in North Hollywood |
|---|---|
| Home Addition (room or second story) | $45,000-$130,000 |
| ADU Construction (detached) | $90,000-$220,000 |
| Garage Conversion ADU | $30,000-$80,000 |
What moves these numbers: the condition of existing framing, whether seismic upgrades are triggered, the complexity of utility tie-ins, and the permit pathway - standard plan check versus the extended review soft-story projects require. We don’t quote by square footage alone because we’ve seen too many North Hollywood projects where the square footage was the least expensive part. Our Free Second Opinion on Any Written Estimate means you can bring a competitor’s quote and we’ll review it line by line at no charge - we’ll show you where the allowances are thin and where the real costs got buried. Call (213) 221-0788 for your written estimate.
We Also Serve Cities Near North Hollywood

Our crews run the full San Fernando Valley corridor - Home Additions & ADU in North Hollywood is our core focus on this page, but we carry the same documentation discipline and written pricing to Studio City, Van Nuys, Burbank, and Glendale. Each city has its own permit office, its own inspection rhythm, and its own housing stock quirks; we don’t paste the same approach across zip codes and hope it fits.
Serving North Hollywood, CA - Our Local Coverage Area
We’re based in the North Hollywood 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 - Home Additions & ADU in North Hollywood

Only if the project alters a tuck-under carport or soft-story footprint - but that’s common enough here that we build it into our initial assessment. The city will flag it at plan check if we haven’t, so we inspect first and price the possibility as an allowance you can see before signing. Call (213) 221-0788 and we’ll review your specific property.
We stop work, photograph the condition, and write a change order with the exact scope and price before proceeding. Our crew opened that 1952 stucco bungalow near Lankershim and Magnolia to find undersized, termite-damaged 2x4s with no shear walls - we added the panels and hold-downs to scope, priced it in writing, and finished on budget. No work proceeds on a change until the change order is signed; that’s the discipline Haven acquired Rowan for.
Three factors: the Northridge-era seismic gaps that trigger mandatory upgrades, the soft-story retrofit pipeline that adds permitting complexity, and the interior valley heat that forces material and scheduling choices coastal contractors don’t face. Out-of-area GCs routinely underbid because they estimate flat square footage without accounting for any of this. Our quotes include the real conditions.
A room addition typically falls in the $45,000-$130,000 range; a detached ADU runs $90,000-$220,000. The lower end assumes sound existing structure and standard finishes; the upper end includes seismic upgrades, extended permitting, and higher-grade materials suited to the valley heat. We deliver a written line-item quote before any work starts - call (213) 221-0788 to schedule your free estimate.
108-113°F summer days force concrete pours before 7 a.m., specify higher-rated roofing underlayments, and size HVAC rough-ins for loads that would be over-engineered west of the 405. Contractors unfamiliar with the San Fernando Valley basin often spec coastal LA materials and blow the schedule when the August heat arrives. We’ve been routing around this for years - it’s standard in our North Hollywood planning.
Written by Grant Rowan, Owner at Rowan Construction Group, serving North Hollywood since 2007.







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