Home Additions & ADU in North Hills - One Fixed Price, Permits Handled

Fast, Reliable Home Additions & ADU Across North Hills

Adding square footage to a North Hills home means planning around a specific set of local realities: slab foundations from the 1950s through 1970s, the lingering structural scars of the 1994 Northridge Earthquake, and City of Los Angeles retrofit ordinances that didn’t exist when most of these houses went up. A home addition or ADU here typically runs $45,000-$130,000 for a room addition and $90,000-$220,000 for a new detached ADU, with garage conversions landing between $30,000 and $80,000. The process starts with a site visit, not a phone estimate. Call (877) 610-1318 to schedule a free walkthrough of your property in North Hills.

Call (877) 610-1318

Tom Barrett has been running crews in the San Fernando Valley since 1998, and the neighborhoods of 91343 and 91393 are home turf for us. We know which blocks off Sepulveda Boulevard have the 1960s soft-story apartment buildings and which streets running north toward Mission Hills are populated with post-war tract homes on slab. That local familiarity changes how we bid a job, because we already know what we’ll find when we open a wall.

Why Barrett & Sons Construction Is North Hills’s Preferred Home Additions & ADU Company

We’re not a franchise dispatching strangers. Tom Barrett’s sons run the crews that work in North Hills, and Tom is on-site most days. When you call our office, a live person answers, not a voicemail box or an out-of-state call center. That matters when you’re planning a six-figure addition and need an answer about a footing inspection or a change order.

Every eligible job in North Hills includes permits pulled and inspections signed. It’s not negotiable with us. The permit inspector works for you, not for us, and that’s exactly why we want him on the property. Too many North Hills homeowners tell us their last contractor suggested skipping permits. The last contractor was wrong, and we say so in writing on every contract.

We also back every finished job with the 90-Day Done Right Promise. If something isn’t done right, one call brings Tom back to make it right. No fine print, no argument. That promise is written into the contract before we ever swing a hammer in North Hills.

Our Home Additions & ADU Services in North Hills

Our Home Additions & ADU team handles the full range of projects in North Hills, from 400-square-foot junior units to whole-second-story additions. Here’s where we focus most of our time in this part of the Valley.

ADU Design & Permitting

North Hills sits under City of Los Angeles jurisdiction, which means ADU plans go through LADBS, not a county process. We handle the drawings, the structural engineering, and the permit package from start to finish. For properties in 91343 near Sepulveda Basin, we also check for potential hillside or flood-zone overlay requirements before we ever submit for plan check. Getting the permit package right the first time saves months and thousands in revision fees.

Garage Conversion ADU

Many North Hills homes built in the 1950s and 1960s have detached two-car garages sitting on slab foundations that were never engineered for living space. Converting one means upgrading the foundation, adding insulation that meets current Title 24 energy codes, and often replacing the old flat roof. A garage conversion in North Hills typically runs $30,000-$80,000 depending on whether we’re doing a simple studio or adding a bathroom and kitchenette. We’ve done enough of these on the streets between Nordhoff and Lassen that we can spot potential drainage problems before the first inspection.

New Detached ADU

A new detached ADU in North Hills starts around $90,000 and can reach $220,000 for a two-bedroom unit with premium finishes. These projects mean new foundations, new utility trenching from the street or the main house, and full LADBS inspections at every stage. The Valley’s hot summers also affect how we sequence the work: we pour concrete and frame early in the day during July and August, and we don’t cut corners on heat illness prevention for our crews. That’s not a sales pitch, it’s how jobs stay on schedule.

Junior ADU & Interior Conversion

A junior ADU, or JADU, is the fastest path to an income unit in North Hills because it converts existing interior space rather than building new square footage. Common candidates are attached garages, large laundry rooms, or a back bedroom with its own exterior door. JADUs in North Hills can often be permitted in under six weeks, and they typically cost far less than a detached unit because there’s no foundation work. We’ve converted several in the pocket of single-story ranchers south of Plummer Street where the original floor plans already had the right layout.

Many of the same homeowners who add an ADU also ask us about Kitchen Remodeling in North Hills or a Bathroom Remodeling in North Hills while we’re already on the property. It makes sense to coordinate the trades while the permits are open and the dumpster is already in the driveway.

Trusted Brands We Service in North Hills

We install materials you can look up, not mystery brands off a van. On our North Hills additions and ADU projects, we regularly use Simonton windows, Ply Gem siding and trim, and PGT impact-rated products where the wind load calculations call for them. Because we stock common parts and order from local supply houses in the Valley, we’re not waiting two weeks for a window sash to ship from out of state mid-project. That keeps your addition from sitting open to the elements while we wait on materials.

Common Home Additions & ADU Problems We See in North Hills Homes

After 29 years working this part of the San Fernando Valley, we know what’s behind the drywall before we open it. Here’s what shows up most often in North Hills.

• Earthquake cosmetics from the mid-1990s. A seasoned North Hills contractor knows to probe any 1990s-era drywall repair or stucco patch for the telltale “earthquake cosmetic”: surface fixes over cracked mudsills, sheared cripple walls, or displaced anchor bolts that were never structurally corrected after the 1994 Northridge Earthquake. Those hidden defects are quietly out of compliance with current LA seismic standards, and they have to be fixed before any addition can be tied into the existing structure.
• Slab foundations with hidden heaving. The Valley’s inland heat and expansive soils cause concrete slabs around North Hills to heave and crack over decades. When we add on to an existing slab home in 91343 or 91393, we trench and inspect the foundation connection points before framing begins. A room addition is only as solid as the foundation it’s bolted to.
• Undersized electrical panels from the 1960s. Most original North Hills tract homes came with 100-amp panels, and many still have them. Adding an ADU with a kitchen, mini-split HVAC, and laundry almost always requires a panel upgrade to 200 amps. We include that cost in our written scope up front so there’s no surprise when LADWP gets involved.
• Santa Ana wind disruptions during framing. Fall wind events rip through the northern Valley and create real safety and scheduling problems on open-framing jobs. We tarp, strap, and sequence our work so a 50-mph gust doesn’t scatter your lumber down the block or send debris through a neighbor’s window. Debris containment is stricter here than in coastal LA, and we build that into the schedule.

Pricing for Home Additions & ADU in North Hills, CA

We Also Serve Cities Near North Hills

Our crews work throughout the San Fernando Valley, so if you’re in North Hills or the surrounding communities of Northridge, Van Nuys, Valley Glen, or San Fernando, we’re close by. Dispatch and scheduling are coordinated from the brand’s Los Angeles office, and crews serve North Hills locally. Your project gets the same owner-operated attention whether we’re one street over or two exits north.

FAQs - Home Additions & ADU in North Hills