From detached guest houses to garage conversions — we handle zoning research, design, permitting, and full construction of accessory dwelling units.
An accessory dwelling unit in Homedale, Idaho is governed by septic, zoning, and water before it is governed by floor plan. Homedale is a roughly 2,881-person Owyhee County farm town on the north bank of the Snake River, and unlike metro Treasure Valley cities with elaborate ADU ordinances on small city lots, the relevant ADU question here is almost always a rural one: can the parcel's septic system and well support a second dwelling, what does Owyhee County (or the City of Homedale, depending on the parcel and the Area of City Impact) actually permit, and how does a second living unit tie into a property that may be agricultural acreage on a private well. The demand is real and specifically Homedale: aging farm parents wanting to stay on family land while a younger generation runs the place, returning adult children, farm-help or seasonal housing, and rental income on land-rich parcels. Iron Crest Remodel (Iron Crest Remodeling Group LLC, RCE-6681702) plans Homedale ADUs from the wastewater, zoning, and water realities backward, confirms jurisdiction per parcel, and builds for the cold semi-arid climate and freeze cycles of southwest Idaho. Free in-home estimates at (208) 779-5551, Monday through Friday, 7 AM to 6 PM.
Build an ADU that adds usable space, flexibility, and long-term property value.
An ADU (Accessory Dwelling Unit) is a self-contained living space on the same lot as an existing home. ADUs have become increasingly popular in the Boise area as housing demand has grown, zoning rules have evolved, and homeowners have recognized the financial and lifestyle benefits of adding a separate living unit to their property. ADU types include detached new construction (a standalone building on the lot), garage conversions (converting an existing garage into living space), attached additions (building a unit that shares a wall with the main home), and basement conversions (converting a finished or unfinished basement into a separate unit with its own entrance). Every ADU project requires careful navigation of local zoning rules, setback requirements, utility connections, parking requirements, and building code compliance. The design must balance livability, code compliance, construction cost, and long-term value. A well-built ADU adds $100,000+ in property value while generating $800-1,500+ per month in rental income in the Boise market.
Homedale homeowners pursue adu construction for a variety of reasons. Here are the most common situations we see:
Not every adu builder project is the same. Here are the most common project types we complete in Homedale:
A standalone structure built on your property — typically 400-1,000 square feet with a bedroom, bathroom, kitchen, and living area. This is the most popular ADU type and offers the most design flexibility.
Convert an existing attached or detached garage into a living space. Includes insulation, drywall, flooring, plumbing, electrical, HVAC, kitchen, and bathroom installation within the existing structure.
Build an ADU that shares one or more walls with the main home but has its own entrance, kitchen, bathroom, and living space. Similar to a home addition but designed as an independent unit.
Convert an existing basement into a separate dwelling unit with its own entrance, kitchen, bathroom, and living area. Requires egress windows, fire separation, and independent utility metering in most jurisdictions.
Predominantly older grain-belt building stock: pre-war wood-sided farmhouses on acreage, post-war ranch homes near the town core, and a substantial manufactured/modular-home share — the great majority on private wells and septic outside the town center.
Hand-built wood-sided farmhouses on irrigated parcels, frequently with original single bathrooms, galvanized supply lines, cast-iron drains, plank subfloors over crawlspaces, minimal insulation, and shallow or rubble foundations.
Ranch and cottage homes around the Idaho Avenue core and Riverside Park; structurally sounder but typically dated finishes, undersized electrical, and single-pane windows.
A large population of HUD-code and modular homes, including park communities, with non-standard openings, moisture-sensitive floor decks, smaller plumbing, and limited electrical capacity.
Limited newer development such as the Santa Fe subdivision with modern systems and builder-grade finishes.
Material selection affects the look, durability, and cost of your adu builder. Here are the most popular options we install in Homedale:
Most detached ADUs in Idaho use a concrete slab-on-grade or stem wall foundation depending on lot conditions, frost depth, and plumbing requirements. Garage conversions may use the existing slab with modifications.
Best for: Detached ADU new construction
2x4 or 2x6 wood framing for walls, with trusses for the roof. ADU framing follows the same building codes as primary residences, including insulation requirements, fire separation, and structural standards.
Best for: All ADU types
The most common heating and cooling solution for ADUs. A ductless mini-split provides efficient heating and cooling with a small exterior compressor and one or two interior wall units. No ductwork required.
Best for: Detached ADUs and garage conversions
ADU kitchens need to be efficient. A compact kitchen typically includes a 24-inch range, apartment-size refrigerator, single-bowl sink, and upper and lower cabinets — all designed to maximize function in a smaller footprint.
Best for: Studio and one-bedroom ADUs
The ADU exterior should complement the main home. Options include matching the existing siding exactly, using a contrasting but compatible material, or using a modern material like board-and-batten or metal panel for a contemporary look.
Best for: Seamless property aesthetic
Here is how a typical adu builder project works from first contact to final walkthrough:
We research your property's zoning designation, lot size, setback requirements, maximum ADU size allowed, parking requirements, and any HOA restrictions. Not every lot qualifies for an ADU, so this step is critical before investing in design.
Based on feasibility findings, we develop a concept design including floor plan, placement on the lot, utility connection points, and exterior style. You receive a preliminary budget range to confirm the project is viable.
Detailed architectural plans are prepared including floor plans, elevations, structural engineering, mechanical systems, and site plan. These plans must meet local building codes and will be submitted for permit review.
We submit plans for permit review, coordinate utility connections (water, sewer, electrical, gas), and manage any required inspections or reviews. ADU permitting can take 4-8 weeks depending on the jurisdiction.
Excavation, grading, utility trenching, and foundation work. For detached ADUs, this typically means a new concrete foundation. Garage conversions may require foundation modifications.
Complete construction including framing, roofing, siding, windows, insulation, drywall, flooring, kitchen, bathroom, HVAC, electrical, plumbing, and all finish work. The ADU is built to the same code standards as a primary residence.
All required inspections are passed, the certificate of occupancy is issued, and the ADU is ready for use. We provide a complete walkthrough and all warranty documentation.
Here is what to expect for project duration when planning a adu builder in Homedale:
| Phase | Duration | Details |
|---|---|---|
| Zoning Research and Feasibility | 1–2 weeks | Confirm the property qualifies for an ADU under current zoning, identify setback and size constraints, and determine utility connection feasibility. |
| Design and Engineering | 4–8 weeks | Architectural plans, structural engineering, site plan, and mechanical design. ADU designs must meet full building code requirements. |
| Permitting | 4–8 weeks | Plan review, permit issuance, and any required revisions. ADU permitting timelines vary by jurisdiction in the Treasure Valley. |
| Site Work and Foundation | 2–4 weeks | Excavation, utility trenching, foundation pour, and curing. Weather-dependent in Idaho, especially during winter months. |
| Framing, Roofing, and Mechanical | 4–8 weeks | Framing, roof installation, windows, exterior sheathing, electrical, plumbing, HVAC, and insulation. All rough-in inspections are completed. |
| Interior Finish and Final Inspection | 4–6 weeks | Drywall, paint, flooring, kitchen, bathroom, fixtures, and all finish details. Final inspections and certificate of occupancy. |
Homedale range: $95,000–$150,000 – $280,000–$420,000
Most Homedale projects: $160,000–$260,000
Homedale ADU pricing is dominated by independent-utility infrastructure and rural systems, not by finish level. The largest single variable is wastewater: a second dwelling almost always implicates the parcel's septic capacity and frequently requires a new or expanded drainfield or a dedicated/upgraded septic system, with Southwest District Health / county review — a substantial, sometimes five-figure scope on its own. The second is water: connecting the ADU to the existing well and pressure system, verifying capacity, and treating hard, iron-bearing groundwater for a second household. The third is the rest of the independent utility package — separate electrical service or sub-panel, a heating/cooling system, and the foundation built to the county's confirmed frost depth. A detached ADU is effectively a small house with its own systems, which is why the floor is well into six figures even at modest size and finish. The low range covers a small, simple detached or attached unit where septic and well capacity already exist or expand cheaply. The average reflects a typical 500–900 sq ft detached ADU with a new or expanded drainfield, full independent utilities, and standard finishes. The high range covers larger units, full septic-system installation, longer utility runs across acreage, and higher finish levels. Regional Treasure Valley labor applies; the Homedale premium is in rural systems engineering.
The final cost of your adu builder in Homedale depends on several factors. Here are the biggest cost drivers:
A detached new-construction ADU costs significantly more than a garage conversion because it requires a new foundation, full framing, roofing, and all-new utility connections. Garage conversions leverage the existing structure.
ADUs range from 300 sq ft studios to 1,000+ sq ft two-bedroom units. Larger units cost more but provide more rental income potential and livability.
Connecting water, sewer, electrical, and gas to the ADU site involves trenching, new service lines, and potentially utility upgrades. Distance from the main house to the ADU affects cost.
Every ADU needs at least a bathroom and kitchen. The finish level — basic vs. mid-range vs. premium — significantly affects the mechanical and finish costs.
Sloped lots, limited access for equipment, rocky soil, or mature trees in the building area can increase site preparation and foundation costs.
ADU permit fees, impact fees, and utility connection fees vary by jurisdiction. Some Boise-area jurisdictions have reduced or waived impact fees for ADUs to encourage construction.
These are the real-world projects we see most often from Homedale homeowners:
The signature Homedale ADU: a self-contained detached unit for aging parents who want to stay on the family land while a younger generation runs the farm. Typically a single-story, accessible 500–900 sq ft unit — no-step entry, accessible bath, blocking for grab bars, an open plan suited to aging in place. The defining work is independent systems: a new or expanded septic/drainfield (Southwest District Health / county review), connection to and capacity verification of the well, separate electrical, and a foundation to county frost depth. Sited for proximity-with-independence relative to the main farmhouse.
Independent housing on the property for a returning adult child or extended family member helping run the operation. Similar systems profile to the elder ADU but typically a standard (rather than aging-in-place) layout and sometimes attached or garage-integrated to reduce cost. Septic and well capacity remain the gating questions; zoning and the Area-of-Impact framework determine what form (attached vs. detached, size caps) is permitted on the specific parcel.
Where an existing outbuilding or garage can be converted, or a new garage built with an ADU above or attached, costs can be contained relative to fully detached new construction — though the unit still needs independent utilities and still implicates septic and well capacity. Conversions of existing rural outbuildings require honest structural, insulation, and code assessment; many farm outbuildings were never built to be habitable and the upgrade cost can approach new construction. We assess feasibility candidly before committing a homeowner to a conversion path.
A permitted detached rental unit on an owner's underutilized acreage as a long-term income asset. The build is similar to the elder ADU but specified for durability and turnover rather than a specific occupant, and the financial case must net the substantial septic, well, and independent-utility cost against realistic local rents. We model that honestly — a rental ADU only pencils when septic and well expansion is reasonable and zoning clearly permits a rented second dwelling on the parcel.
A code-compliant, durable unit to house agricultural help — a legitimate, permitted alternative to substandard ad hoc arrangements on working operations. Typically simpler finishes, robust and easy to maintain, sited for operational logistics. Still a full independent-systems build subject to septic, well, and zoning review; the difference is in the finish and durability brief, not the infrastructure.
Solution: A detached ADU on your property generates $800-1,500+ monthly rental income while you continue living in your primary home.
Solution: An ADU with a separate entrance provides privacy and independence while keeping family close. Accessibility features can be built in from the start.
Solution: A garage conversion ADU transforms underutilized space into a functional living unit at a lower cost than new construction.
Solution: A detached ADU configured as a studio or office provides the separation remote workers need, with the commute of a backyard walk.
Solution: A well-built ADU adds $100,000+ to property value and generates ongoing rental income — one of the highest-ROI improvements a homeowner can make.
Cold semi-arid (Köppen BSk): hot dry summers peaking near 104°F, winters near and below freezing with repeated freeze-thaw, intense high-desert UV, open-country wind on ag parcels, and ~10 inches annual precipitation. Elevation ~2,241 ft.
Rapid degradation of exterior coatings, decking, and glazing; UV-stable, high-performance materials required.
Frost heave on shallow footings and moisture intrusion behind failing siding; footings to county frost depth and freeze-protected supply lines required.
High heating/cooling load in under-insulated stock; envelope and glazing upgrades deliver outsized comfort and cost returns.
Unbuffered ag parcels raise wind requirements on siding systems, attachments, and deck/structure connections.
Affects flooring acclimation, paint cure, and material movement; proper acclimation and detailing needed.
The original gridded town center along Idaho Avenue, Homedale's main commercial street, with the oldest concentrated 1920s–1950s housing on small platted lots; more likely on city water and sewer than surrounding acreage.
Common projects in Old Homedale Townsite / Idaho Avenue Core:
Homes near Riverside Park and the Snake River, including post-war ranch stock; some parcels are within or near the river's FEMA floodplain.
Common projects in Riverside Park / Snake River Frontage:
Among Homedale's newer residential development, near schools, retail, and the route toward the Owyhee reservoir; modern construction with builder-grade finishes.
Common projects in Santa Fe Subdivision:
Irrigated farm acreage outside the town limits — larger lots on private wells and septic, with farmhouses and outbuildings; the rural-systems variables peak here.
Common projects in Surrounding Owyhee County Ag Parcels:
A large manufactured- and modular-home population, including parks such as Sunset Village on South Main, requiring structure-specific remodeling methods.
Common projects in Manufactured-Home Communities (e.g., Sunset Village):
Every Homedale neighborhood has different housing stock, homeowner priorities, and project considerations. Here is what adu builder looks like in each area:
Permit authority: Owyhee County Building Department (Homedale office, 130 W. Idaho Ave.); City of Homedale for certain in-city parcels under the Homedale Area of City Impact
Online portal: owyheecounty.net/departments/building-department/
Here are the design trends we see most often in Homedale adu builder projects:
Homedale-area home values are estimated in roughly the mid-$200,000s (a 2024 estimate places the median near $253,806), with median household income near the mid-$60,000s (~$64,804) and a high rate of long-tenure, owner-occupied households; about 38.7% of residents are Hispanic or Latino. Most remodeling here is a stay-and-use, decades-long investment rather than a resale flip, which prioritizes durability, well-water resilience, and aging-in-place function over trend-driven styling. Figures are third-party estimates and should be confirmed against current assessor/Census data.
Avoid these common pitfalls Homedale homeowners encounter with adu builder projects:
Better approach: A second dwelling almost always implicates the parcel's septic system. Determine the septic/drainfield solution and Southwest District Health / county review path before architecture — it is the dominant feasibility and cost driver.
Better approach: Under the Homedale/Owyhee Area of City Impact, whether an ADU is permitted, in what form, and whether it can be rented is a per-parcel determination split between the city and county. Confirm the governing jurisdiction and zoning before committing to a design.
Better approach: A detached ADU needs its own electrical, heating/cooling, well connection with verified capacity, and code-depth foundation in addition to septic. Budget it as a small standalone house, not as an add-on, so the six-figure floor is not a shock.
Better approach: Most farm outbuildings were not built habitable; code-compliant conversion can approach new-build cost while still needing full utilities and septic/well review. Get a candid structural and code assessment before choosing the conversion path.
Better approach: Net the real septic, well, and utility cost against realistic local rents, and verify zoning permits a rented second dwelling on the parcel. If the numbers only work on best-case assumptions, they do not work.
Better approach: A new detached dwelling near the Snake River may fall in a FEMA Special Flood Hazard Area with elevation and construction-standard implications. Confirm flood status by address before design.
Three things, in order: the parcel's septic capacity, the governing zoning, and the well/water supply. Because most Homedale-area parcels are on private septic, a second dwelling usually requires a new or expanded drainfield or septic system with Southwest District Health / county review — that is the first feasibility gate. Zoning is the second: whether an ADU is allowed, in what form, and whether it can be rented depends on the governing jurisdiction, which (given the Homedale/Owyhee Area of City Impact) is determined per parcel. Well and pressure capacity for a second household is the third. We resolve all three before design, because assumptions here are expensive.
It depends on the parcel. Homedale and Owyhee County maintain a designated Area of City Impact, so the governing jurisdiction can be the City of Homedale or Owyhee County depending on where the property sits. Most rural acreage ADUs route through the Owyhee County Building Department (local office at 130 W. Idaho Ave.) with building, plumbing, electrical, and mechanical permits plus septic review. We confirm the governing jurisdiction per address before proceeding rather than assuming.
Because a detached ADU here is effectively a small standalone house with its own septic solution, well connection, electrical, heating/cooling, and code-depth foundation. On a rural parcel the wastewater scope alone — a new or expanded drainfield or dedicated septic system with environmental review — can be a five-figure line item before the unit is framed. The infrastructure, not the finishes, drives the cost, which is why even a modest detached unit starts well into six figures.
Yes — that is the most common and highest-intent Homedale ADU. We build these single-story and accessible (no-step entry, accessible bath, grab-bar blocking), sited for proximity-with-independence from the main farmhouse, with full independent systems. The work is gated by septic and well capacity and the per-parcel zoning answer, which we confirm at the outset so the project is feasible before design is locked. It is a durable way to keep an aging generation on inherited land.
Sometimes, but only with honest math. A rental ADU must net the substantial cost of septic expansion, well capacity, and full independent utilities against realistic local rents, and zoning must clearly permit a rented second dwelling on the parcel. On a land-rich parcel where septic and well expansion is reasonable and zoning is favorable, it can be a sound long-term asset; where septic requires a major new system, the numbers often do not work. We model it candidly rather than assuming it pencils.
Possibly, but most rural outbuildings were never built to be habitable, and bringing one to code for foundation, insulation, structure, and life-safety can approach new-construction cost while still requiring full independent utilities and septic/well review. We assess the specific structure candidly before recommending a conversion path, because a conversion that looks cheap on the surface often is not once code requirements are applied.
Yes. ADU projects require building permits, plan review, and multiple inspections. In most Boise-area jurisdictions, ADUs also require zoning compliance review to confirm lot size, setbacks, and parking requirements are met. We handle the entire permitting process.
A detached new-construction ADU typically costs $120,000-200,000+ in the Boise area, depending on size, finish level, and site conditions. A garage conversion is typically $80,000-150,000. Costs include design, engineering, permitting, construction, and utility connections.
From start of design to move-in, a typical ADU project takes 6 to 12 months. This includes design (4-8 weeks), permitting (4-8 weeks), and construction (3-5 months). Garage conversions are faster; detached new construction takes longer.
In most Boise-area jurisdictions, yes. ADUs can be rented as long-term rentals. Short-term rental rules (Airbnb, VRBO) vary by city and may have additional restrictions. Check local regulations before planning a short-term rental strategy.
A well-built one-bedroom ADU in the Boise area can generate $800-1,500+ per month in rental income, depending on location, size, finish level, and market conditions. This income can offset or exceed the monthly cost of financing the ADU construction.
Maximum ADU size varies by jurisdiction. In Boise, detached ADUs can be up to 1,000 square feet or 10% of the lot area, whichever is less. Other cities in the Treasure Valley have different size limits. We confirm the specific rules for your property during the feasibility phase.
Get a free, no-obligation estimate for adu construction in Homedale, ID. We handle design, permits, and every detail of construction.
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