Free written scope consultation - allowances, timeline, and change-order rules on paper before a single trade is scheduled
Fast, Reliable Home Additions & ADU Across Lemmon Valley
A home addition or ADU in Lemmon Valley typically runs $45,000-$130,000 for an addition, and $90,000-$220,000 for a detached ADU, with garage conversions landing between $30,000-$80,000. Those numbers move based on foundation work, septic or sewer availability, and flood zone requirements that are unique to this basin. We know Lemmon Valley because our crews work here weekly, not occasionally. Call (877) 610-1318 and Tom or one of his sons will give you a straight answer about your specific lot.
Why Barrett & Sons Construction Is Lemmon Valley’s Preferred Home Additions & ADU Company
Tom Barrett founded this company in 1998, and he still answers his own phone. That matters in a place like Lemmon Valley, where the contractor who gave you a quote eight months ago might not return the call when the county flags your FEMA flood zone mid-permit. Our crews know the difference between a lot on Limber Pine Drive and one off Patrician Drive, because we’ve poured footings on both. We’ve pulled permits through Washoe County for ADUs and additions in 89506, and we’ve sat through enough building-department conversations to know what gets approved and what gets kicked back. Reviews from Lemmon Valley customers mention the same thing: the price we quoted was the price they paid, and the change orders came in writing before any scope shifted.
We’re not a franchise dispatching strangers from another state. Tom’s sons run the crews. When you call about a Home Additions & ADU project in Lemmon Valley, you’re talking to someone who’ll likely be standing in your driveway later that week. Our 90-Day Done Right Promise is written on every contract: if something isn’t right, one call brings Tom back. No squabbling, no “that was a sub’s fault.”
Our Home Additions & ADU Services in Lemmon Valley
ADU Design & Permitting
Lemmon Valley sits in a closed hydrologic basin, which means every ADU permit here starts with a drainage conversation. We handle the full design and permitting package, from site plan through structural drawings, before you spend a dime on materials. Washoe County’s current FEMA flood maps govern what you can build and how high, and we’ve found that homeowners who skip this step end up with a denial letter and a year of wasted time. You’ll get a written scope with every allowance itemized, and a permit set that the county signs off on.

Garage Conversion ADU
Many Lemmon Valley homes from the 1970s-1990s were built with attached garages on slab. Converting one into a rentable unit runs $30,000-$80,000, depending on whether you need plumbing cut into the slab, separate metering, or a full kitchen. Because snowmelt in this basin has nowhere to drain, we pay extra attention to slab moisture and perimeter drainage before we frame interior walls. A garage conversion here isn’t the same as one in Sparks, where groundwater behaves differently.

New Detached ADU
A new standalone ADU on a Lemmon Valley lot runs $90,000-$220,000. The wide spread comes down to site specifics: stable native soil versus fill, sewer connection distance, and whether the lot falls inside a current FEMA flood zone. On parcels near Swan Lake, where county buyouts left vacant lots beside occupied homes, we often have to design for conditions no 1980s builder anticipated. Our Home Additions & ADU team knows how to elevate a slab, add flood vents, and keep the permit moving.

Junior ADU & Interior Conversion
A junior ADU, typically a converted bedroom or bonus room with a small kitchenette, is the most affordable path in Lemmon Valley. These often involve sharing an existing bathroom, which keeps plumbing work minimal. We see a lot of these on Rancho Haven and other north Lemmon Valley streets where ranch homes have spare rooms that never got used. It’s a smart move for a parent, an adult child, or short-term rental income, and we handle the interior separation, egress compliance, and any electrical panel upgrades the load calc demands.

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.
Trusted Brands We Service in Lemmon Valley
We install materials you can look up. When we build an ADU or addition, the windows typically come from Andersen or Marvin, and when plumbing work is involved we lean on Grohe fixtures and Schluter waterproofing for wet areas. No mystery brands off a van. That matters when the county inspector asks about flashing details or a homeowner wants to verify what they’re paying for. We order direct for Lemmon Valley jobs, and when a replacement part is needed mid-project we don’t have to hunt through three states to find it.
Common Home Additions & ADU Problems We See in Lemmon Valley Homes
- High groundwater from snowmelt. Lemmon Valley gets more snow than the Reno valley floor, and with no outlet stream, that melt sits. We regularly see slabs with moisture wicking through, which means any addition needs a drainage plan before concrete shows up.
- Split-block flood designations. Some lots near Swan Lake were remapped under modern FEMA zones after the 2017-2019 flooding, while the house next door still carries the old designation. You can’t assume your addition is exempt because your neighbor’s wasn’t flagged.
- Foundation retrofits on 1970s-90s construction. Most Lemmon Valley housing stock is single-story ranch or manufactured on slab, built before the basin’s drainage problem was well understood. Additions often require perimeter waterproofing and elevated framing.
- Utility distance challenges. Many Lemmon Valley parcels are long and skinny, which means sewer lines, gas feeds, and electrical service don’t always reach where an ADU wants to sit. That’s a cost item most homeowners don’t budget for.
Pricing for Home Additions & ADU in Lemmon Valley, NV
Home additions in Lemmon Valley run $45,000-$130,000. ADU construction runs $90,000-$220,000 for a detached unit, while garage conversions land between $30,000-$80,000. What moves the number: whether you’re on septic or sewer, how far the utilities have to run, flood zone elevation requirements, finish level, and whether the existing panel needs an upgrade. Every quote we give you includes a line-item breakdown, and every allowance is in writing. If a change surfaces mid-job, you’ll see it as a written change order before work proceeds. No surprise invoices. Call (877) 610-1318 and we’ll walk your lot and give you a real number, free.
Key Takeaways:
- Home additions: $45,000-$130,000
- Detached ADU: $90,000-$220,000
- Garage conversion: $30,000-$80,000
- Junior ADU and interior conversion: typically the lowest-cost option
- Flood zone and groundwater conditions affect every Lemmon Valley project
We Also Serve Cities Near Lemmon Valley
Our crews work regularly in Home Additions & ADU in Lemmon Valley, Cold Springs, Sun Valley, Reno, and Sparks. If you’re on the edge of 89506 or just across the county line, we can often help with Kitchen Remodeling in Lemmon Valley and Bathroom Remodeling in Lemmon Valley as part of a larger addition. Call and ask; the worst we’ll say is we’re booked out a few weeks.
Serving Lemmon Valley, NV - Our Local Coverage Area
We’re based in the Lemmon Valley 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 Lemmon Valley
A live person answers the phone 24/7 at (877) 610-1318, and Tom or one of his sons can typically schedule a site walk in Lemmon Valley within days, not weeks. Because crews work here regularly, we don’t tack on travel time or treat Lemmon Valley as an out-of-area trip. Call and you’ll get a real conversation, not a voicemail box.
Yes. We work throughout 89506, including the neighborhoods near Swan Lake, Patrician Drive, Limber Pine Drive, and the older ranch tracts north of Stead. If you’re on a lot that was affected by the 2017-2019 flooding or sits near a county buyout parcel, we’re familiar with the permitting complications and the drainage work those projects require.
Not without your signature. Our rule is simple: every scope, every allowance, and every price change arrives as a written change order before any work happens. If we hit a condition we couldn’t see, like a buried debris pit or a utility line in the wrong place, you’ll know about it and approve the delta before a single new nail goes in. The allowance that isn’t on paper is a surprise waiting for a date, and we don’t do that.
Expect to pay more here for foundation and drainage work. Reno and Sparks lots don’t usually contend with a closed hydrologic basin and spring snowmelt that has nowhere to drain. In Lemmon Valley, a project may need elevated slab design, flood vents, or perimeter waterproofing that a comparable job in Reno would skip, and that adds $5,000-$20,000 depending on the site. Call (877) 610-1318 for a free estimate specific to your parcel.
Every job carries our 90-Day Done Right Promise: if it’s not done right, Tom Barrett comes back and makes it right, one call. That’s in writing on the contract, not buried in fine print. Beyond that, our workmanship standards match what the county inspector signs off on, and we don’t consider a job done until the final inspection passes. If something’s wrong, we want to know about it.
Written by Tom Barrett, Owner at Barrett & Sons Construction, serving Lemmon Valley and northern Washoe County.







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