ADU Site Prep & Utilities Cost - One Fixed Price, Permits Handled

How Much Does ADU Site Prep & Utilities Cost in Van Nuys?

Our ADU Site Prep & Utilities services in Van Nuys typically run $18,000 to $65,000, depending on lot conditions, how far utility connections need to travel, and whether grading is involved. Most straightforward Van Nuys projects – a flat lot with reasonable utility access – land between $22,000 and $38,000 all-in. That range covers demolition, grading, trenching, and the water, sewer, gas, and electrical laterals required to bring a new ADU to code.

At Ellery ADU Studio, every site prep and utilities scope is quoted at a written price before any work starts – that’s Haven Standard Clause 1, and it applies to every project we take on. You’ll know the number before a single shovel hits the ground.

ADU Site Prep & Utilities Cost Breakdown (2026)

The table below reflects what Ellery ADU Studio sees in the Van Nuys market in 2026. These are real ranges drawn from projects across the area, not national averages ported in from somewhere else. Van Nuys sits in the north-central San Fernando Valley, which means clay-heavy soils in lower lots near the L.A. River flood corridor, and older utility infrastructure in neighborhoods like Vintage Gardens and Delano Street that can add scope to what looks like a simple connection on paper.

A few things push projects toward the high end more than any other: the distance from the proposed ADU footprint to the nearest city sewer main, whether the existing electrical panel needs a full upgrade, and whether there’s concrete – driveways, patios, or old slabs – sitting over the utility path. In Van Nuys, we see a lot of 1960s ranch homes on wide lots where the logical ADU placement is at the far rear of the property. That extra 80 to 120 feet of trench run on water, sewer, and electrical can add $8,000 to $15,000 to the utilities scope alone.

All of this appears as line items in the written scope you receive before work starts. No range-to-actuals adjustment after the fact. That’s what a written upfront price actually means – and it’s how Ellery ADU Studio has operated on every one of the 900-plus ADUs we’ve taken from design through final inspection since 2015.

What Affects ADU Site Prep & Utilities Pricing in Van Nuys

Site prep costs don’t vary randomly – they vary based on specific, measurable conditions. Here’s what actually moves the number in the Van Nuys market:

• Distance to city utilities: The single biggest variable. Van Nuys parcels on streets where the sewer main runs in the alley – like many blocks south of Victory Boulevard – are often cheaper to connect than lots where the main is in the front street and the ADU is at the back of a 150-foot deep lot. Every additional linear foot of trench adds cost for excavation, pipe, bedding material, compaction, and surface restoration.
• Existing electrical service capacity: A large share of Van Nuys housing stock was built between 1950 and 1975 with 100-amp electrical service. California’s 2025 Title 24 energy code requires ADUs to meet current efficiency standards, and most lenders and inspectors won’t sign off on a new unit drawing from an undersized panel. Upgrading from 100-amp to 200-amp service typically runs $2,500 to $5,500 for the panel work alone, before the ADU subpanel is factored in.
• Soil conditions: Van Nuys soils aren’t uniform. Lots in the lower portions of the valley near the Tujunga Wash and the L.A. River flood plain have expansive clay soils that can complicate trenching and require engineered bedding for sewer laterals. The geotechnical report – typically $1,800 to $3,200 – will flag this before any digging starts, not after.
• Existing hardscape over utility paths: If the utility trench needs to run under a concrete driveway, a pool deck, or a covered patio, the concrete has to come up and go back. Cutting, removing, and patching concrete adds $25 to $75 per linear foot to the trench run cost, depending on thickness and reinforcement.
• All-electric vs. gas-served ADU design: Projects designed as all-electric from the start – using heat-pump HVAC, induction range, and electric water heating – skip the gas line extension entirely. That’s $1,200 to $4,500 removed from the scope before a single decision is made. Given SoCalGas’s current rate trajectory and California’s building code direction, we’re seeing more Van Nuys clients choose all-electric even when gas is available at the meter.
• Lot size and ADU placement: Van Nuys has a mix of R1 lots typically 50 to 70 feet wide and deeper RS lots, some extending 150 feet or more. A rear detached ADU on a deep lot means longer utility runs in every trade. A junior ADU conversion inside the existing house – which our ADU Site Prep & Utilities in Van Nuys page covers in detail – often requires far less site work, since most utilities are already at the main structure.
• Permit timing and LA DBS processing: The City of Los Angeles Department of Building and Safety has made real progress on ADU permit processing since 2022, and standard ADU permits in Van Nuys are now often approved in 4 to 10 weeks for by-right projects. Projects requiring a sewer capacity study or a variance add time, and some utility connection fee schedules are tied to approval dates. Getting the permit set right the first time – not revising it twice – matters to the schedule and, indirectly, to cost.

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Van Nuys-Specific Site Conditions Worth Knowing

Van Nuys sits between Reseda to the west, North Hollywood to the east, and Sherman Oaks to the south. The flat valley floor geography means most lots don’t require significant grading, which keeps that line item manageable compared to hillside markets like Encino Hills or Studio City’s canyon properties. But that flat topography also means drainage has to go somewhere deliberate. Storm water management and proper site drainage – required under LA’s Low Impact Development ordinance – adds a line item that some estimates leave out until the permit set is reviewed.

The neighborhood around Kester Avenue and Oxnard Street, for example, has older combined sewer infrastructure that the city has been progressively separating. Depending on where your parcel falls in that upgrade cycle, a sewer connection that looks standard might require coordination with LA Sanitation on lateral sizing. We’ve worked through this on Van Nuys projects enough times to know to check the sewer atlas before pricing the lateral, not after.

Homes along the stretch of Hazeltine Avenue between Victory Boulevard and Vanowen Street often have utility easements running across the rear of the lot – a condition that can limit where an ADU can be legally placed, or require additional coordination with LADWP if the easement covers an overhead electrical line. The permit set catches this. A verbal estimate from a subcontractor who hasn’t pulled the lot records won’t.

How to Save on ADU Site Prep & Utilities

There’s real money to save in the site prep and utilities phase – but most of it comes from planning decisions made before any work is priced, not from negotiating after the fact.

Design the ADU placement around existing utility access. If the sewer cleanout is near the garage and you have the flexibility to place the ADU near that point, you can cut a 100-foot trench run down to 30 feet. That’s a meaningful difference. Ellery’s design-build model is specifically structured so that the architect and the site crew are working from the same contract – so placement decisions made at the drawing stage account for what the trench crew will actually encounter.

Choose all-electric from the start. Skipping the gas line isn’t a sacrifice in 2026 – modern heat-pump systems outperform gas in heating efficiency and have lower operating costs over time. The gas line extension budget – typically $1,200 to $4,500 – stays in your pocket, and there’s no SoCalGas connection fee to pay.

Don’t replace the main house panel if you don’t have to. Some electrical contractors will recommend a full panel replacement when a subpanel and a dedicated feeder to the ADU might be sufficient. The correct answer depends on the existing panel’s condition and capacity, not on what’s easiest to quote. We document what we find – including a photo record of the existing panel condition – before recommending an upgrade scope.

Bundle site prep with the full ADU contract. When site prep is a separate contract from design and construction, scope gaps open up between trades. The designer specifies something the site contractor didn’t budget for, or the site contractor leaves a condition that the framing crew now has to work around. Under Ellery’s one-contract design-build model, that gap doesn’t exist – and you’re not paying two sets of mobilization costs or carrying two sets of insurance coordination.

Get a second opinion on any written estimate you already have. If you’ve received a site prep or utilities estimate from another firm and want to know whether the scope and pricing make sense for Van Nuys, Ellery offers a free second opinion on any written estimate. Call (424) 523-8492 and we’ll review the scope with you – no obligation, no sales pitch. If the estimate is fair and the scope is complete, we’ll tell you.

Confirm what’s included in utility connection fees. LADWP and SoCalGas both charge connection and capacity fees that are set by the utility – no contractor can reduce them. But some estimates quote the trench work and leave the utility fees as a “to be determined” line item. Those fees are determinable: they’re published on the utility’s fee schedule. Ask that they be included in the written quote before you sign anything.

FAQs – ADU Site Prep & Utilities Cost in Van Nuys

How much does ADU site prep cost in Van Nuys, CA in 2026?

ADU site prep in Van Nuys runs $18,000 to $65,000 depending on site conditions, with most standard flat-lot projects landing in the $22,000 to $38,000 range. That figure includes demolition, grading, utility trenching, water and sewer laterals, electrical work, and permits. Complex sites – long sewer runs, panel upgrades, or significant concrete removal – push toward the upper end. Call (424) 523-8492 for a written quote specific to your Van Nuys lot; Ellery provides a written price before any work starts on every project.

What utility connections does a new ADU in Van Nuys require?

A new detached ADU in Van Nuys requires four utility connections: water (a new lateral or upsized service from LADWP), sewer (a lateral to the city main), electrical (a dedicated feeder from the main panel or a new subpanel), and gas (if the unit isn’t designed all-electric). Each of these is permitted separately and inspected independently. The combined utility connection scope typically accounts for 55 to 70 percent of total site prep cost. For all-electric ADU designs, the gas line is eliminated, reducing both cost and utility coordination time.

Does Van Nuys require a soils report for an ADU?

For a new detached ADU with a new foundation, the City of Los Angeles generally requires a geotechnical (soils) report. The report costs $1,800 to $4,500 depending on lot size and the complexity of the soil conditions found. In Van Nuys, lots near the Tujunga Wash or in the lower valley floor are more likely to have expansive clay soils that affect foundation design – and foundation design directly affects construction cost. Garage conversions and junior ADUs that use the existing foundation often skip this requirement, though a structural engineer’s sign-off is still typically required.

How long does ADU site prep take in Van Nuys?

Physical site prep work – demo, grading, trenching, and utility rough-in – typically takes 3 to 8 weeks once permits are in hand. The permit phase for site prep work in Van Nuys (submitted through the City of LA Department of Building and Safety) currently runs 4 to 10 weeks for standard by-right ADU projects. Utility inspections and connection scheduling with LADWP and SoCalGas add time that varies by their current workload. Total time from contract signing to completed site prep, including permitting, is typically 3 to 5 months for a Van Nuys project.

Is ADU site prep included in Ellery’s design-build contract?

Yes. ADU site prep and utilities is one of the five service categories covered under Ellery ADU Studio’s single-contract design-build model – alongside ADU Design & Permitting, Garage Conversion ADU, New Detached ADU, and Junior ADU & Interior Conversion. The written price you receive before work starts covers the full scope, from site survey through utility inspections, with no separate contractor for the site work. The 365-Day Done Right Promise applies to site prep just as it does to finished construction: if the work isn’t built to the permitted drawings, Ellery makes it right in writing. Call (424) 523-8492 – a live person answers – to discuss your Van Nuys site and get a written scope.

Can I get a second opinion on a site prep estimate I already have?

Yes, and it costs nothing. Ellery ADU Studio offers a free second opinion on any written estimate for ADU site prep or utilities work in the Van Nuys area. Bring the written scope and pricing you’ve received and we’ll review it line by line – flagging what’s included, what’s commonly missing, and whether the numbers reflect current Van Nuys market conditions. There’s no obligation to work with us afterward. Call (424) 523-8492 to schedule a review.

What You Get With Ellery ADU Studio’s Written Quote

A written price is only as useful as the scope it’s attached to. Ellery’s site prep and utilities quotes include a line-itemized scope covering every trade – demo, grading, trenching, water lateral, sewer lateral, electrical, gas (if applicable), permits, and utility connection fees – with quantities and unit costs visible. Nothing is bundled into a single “site work” line that obscures what you’re actually paying for.

Under Haven Standard Clause 1, that written price is fixed at signing. Not a range with an asterisk. Not “subject to field conditions.” The field conditions are assessed before the quote is written – that’s why we pull lot records, utility atlas maps, and existing panel documentation before a number goes on paper.

The documented photo record comes with every site visit: what we found, what we did, and what condition the site was left in. That documentation isn’t just for Ellery’s records – it’s yours, delivered to you, and it forms the evidence trail that backs the 365-Day Done Right Promise.

Nadia Ellery founded this studio in 2015 specifically to close the gap between design and construction on ADU projects – the gap where most cost overruns and schedule failures originate. Site prep and utilities is exactly where that gap shows up most visibly: a designer who specifies a sewer location without checking the depth of the city main, or a contractor who bids grading without reviewing the soil report. The single-contract model eliminates that gap because the person writing the permit set and the crew doing the site work are accountable to the same written scope.

If you’re planning an ADU on a Van Nuys lot, the home page lays out how the full design-build process works from initial quote through final inspection. Site prep isn’t the first conversation – but it’s often the one where the real project cost becomes clear, and it’s better to have that conversation with numbers on the table than to find out what the site requires after you’ve already committed to a construction contract.

Key Takeaways

• ADU site prep and utilities in Van Nuys runs $18,000 to $65,000, with most standard projects between $22,000 and $38,000.
• The biggest cost variables are sewer lateral distance, electrical panel capacity, and how much concrete sits over the utility path.
• Van Nuys-specific factors – older utility infrastructure in established neighborhoods, clay soils near the Tujunga Wash, and deep valley-floor lots – can push costs beyond what a generic estimate anticipates.
• All-electric ADU designs eliminate the gas line scope ($1,200 to $4,500) and simplify utility coordination.
• Ellery ADU Studio provides a written, line-itemized price before any site work begins, per Haven Standard Clause 1 – no verbal ballparks, no post-work adjustments.
• A free second opinion is available on any written estimate you already have. Call (424) 523-8492.
• The 365-Day Done Right Promise covers site prep and utilities work the same as finished construction.

Get a Written Site Prep & Utilities Quote for Your Van Nuys Property

If you have a Van Nuys lot and want to know what site prep and utilities will actually cost for your specific conditions, call Ellery ADU Studio at (424) 523-8492. A live person answers – no voicemail queue, no callback promise that may or may not materialize. We’ll review your lot, pull the relevant utility records, and give you a written price before any work starts. That’s the only kind of quote Ellery issues.

If you already have a written estimate from another firm, bring it. The free second opinion review is available to any Van Nuys homeowner, and it costs nothing to find out whether what you’ve been quoted reflects what the site actually requires.

Written by Nadia Ellery, Owner at Ellery ADU Studio Van Nuys, serving Van Nuys since 2015. Pricing reflects the Van Nuys market as of 2026. Ellery ADU Studio Van Nuys offers free estimates – call (424) 523-8492.