ADU Construction in Meridian, ID
From detached guest houses to garage conversions — we handle zoning research, design, permitting, and full construction of accessory dwelling units.
Build an ADU that adds usable space, flexibility, and long-term property value.
Licensed general contractor with ADU-specific experience in IdahoIn-depth knowledge of local ADU zoning rules across Boise-area jurisdictionsFull architectural design and engineering includedComplete permitting management from application through certificate of occupancy
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.
Meridian homeowners pursue adu construction for a variety of reasons. Here are the most common situations we see:
- ✓Homeowners who want rental income from a detached or attached unit on their property
- ✓Families who need a guest house, in-law suite, or multigenerational living space
- ✓Remote workers or creatives who want a separate studio, office, or workshop space
- ✓Property investors who want to increase property value and utility with an ADU
- ✓Homeowners who want housing flexibility — rent now, use for family later, or vice versa
Not every adu builder project is the same. Here are the most common project types we complete in Meridian:
Detached ADU (New Construction)
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.
Garage Conversion ADU
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.
Attached ADU Addition
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.
Basement ADU Conversion
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.
Meridian's housing stock is predominantly post-1990 construction. The majority of homes feature PEX plumbing, 200-amp electrical panels, and energy-efficient windows — but with builder-grade interior finishes that homeowners upgrade as the homes age.
1990s (North Meridian)
Early subdivision homes with standard 90s finishes: oak cabinets, laminate countertops, carpet throughout, and basic tile in bathrooms. These homes are 25-35 years old and are the most common full-remodel candidates.
2000s–2010s (South Meridian, Paramount)
Larger homes with better floor plans but still builder-grade finishes. Many have slab granite installed during the granite boom but are now dated. Cabinets, fixtures, and flooring are the primary upgrade targets.
2015–present (South Meridian expansion)
Newer construction with open floor plans and modern systems. Homeowners typically upgrade finishes 3-7 years after purchase — replacing builder-grade countertops, cabinet hardware, lighting, and flooring.
Common issues in Meridian homes
- •Builder-grade cabinets with particle board shelves and basic hinges wearing out
- •Outdated builder-selected finishes (honey oak, Tuscan tile, slab granite) that feel dated
- •Closed-off floor plans in 1990s homes with walls between kitchen and living areas
- •Insufficient kitchen storage and counter space for today's cooking and entertaining
- •Basic builder lighting that does not adequately illuminate kitchens and bathrooms
- •Original carpet throughout that homeowners want to replace with hard flooring
Material selection affects the look, durability, and cost of your adu builder. Here are the most popular options we install in Meridian:
Concrete Slab or Stem Wall Foundation
$8,000–$20,000Most 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
Standard Wood Framing
$12–$22 per sq ft framed2x4 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
Mini-Split HVAC System
$3,500–$7,000 installedThe 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
Compact Kitchen Package
$5,000–$15,000 completeADU 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
Matching or Complementary Siding
$5–$15 per sq ft installedThe 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:
1
Zoning and Feasibility Research
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.
2
Concept Design and Budget Planning
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.
3
Architectural Plans and Engineering
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.
4
Permitting and Utility Coordination
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.
5
Site Preparation and Foundation
Excavation, grading, utility trenching, and foundation work. For detached ADUs, this typically means a new concrete foundation. Garage conversions may require foundation modifications.
6
Construction (Framing through Finish)
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.
7
Final Inspection and Certificate of Occupancy
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 Meridian:
| 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. |
Typical range: $80,000 – $300,000+
Most projects: $120,000–$200,000
The final cost of your adu builder in Meridian depends on several factors. Here are the biggest cost drivers:
ADU Type (Detached vs. Conversion)
high impactA 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.
Size (Square Footage)
high impactADUs 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.
Utility Connections
high impactConnecting 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.
Kitchen and Bathroom Complexity
medium impactEvery ADU needs at least a bathroom and kitchen. The finish level — basic vs. mid-range vs. premium — significantly affects the mechanical and finish costs.
Site Conditions and Access
medium impactSloped lots, limited access for equipment, rocky soil, or mature trees in the building area can increase site preparation and foundation costs.
Permitting and Impact Fees
medium impactADU 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.
Problem: Need rental income but do not want to move
Solution: A detached ADU on your property generates $800-1,500+ monthly rental income while you continue living in your primary home.
Problem: Aging parents need close but independent living space
Solution: An ADU with a separate entrance provides privacy and independence while keeping family close. Accessibility features can be built in from the start.
Problem: Existing garage is unused and taking up valuable space
Solution: A garage conversion ADU transforms underutilized space into a functional living unit at a lower cost than new construction.
Problem: Need a dedicated workspace separate from the main home
Solution: A detached ADU configured as a studio or office provides the separation remote workers need, with the commute of a backyard walk.
Problem: Want to maximize property value and investment potential
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.
Meridian shares Boise's semi-arid climate with hot summers, cold winters, and low humidity. The same material and construction considerations apply — UV resistance for exterior materials, freeze-thaw durability, and proper insulation.
Hot Summers (90-105°F)
Exterior materials and finishes must resist UV degradation. West-facing windows and walls get the most sun exposure. Proper insulation and HVAC sizing are critical for comfort.
Cold Winters (15-30°F)
Frost depth requirements affect foundation work for additions and ADUs. Plumbing in exterior walls and crawl spaces needs freeze protection.
Wind and Dust
Meridian's open terrain means more wind and dust exposure than central Boise. Exterior finish quality and window sealing matter for long-term durability.
Low Precipitation
Less rain means less exterior moisture exposure, which is favorable for siding and paint longevity. However, irrigation and ground moisture around foundations still require attention.
South Meridian
The largest and fastest-growing area, with subdivisions built from 2005 to present. Homes range from 1,500 to 3,500+ square feet with builder-grade finishes that homeowners customize over time.
Common projects in South Meridian:
- •Kitchen remodels upgrading builder cabinets and countertops
- •Bathroom remodels converting tub/shower combos to walk-in showers
- •Outdoor living — decks, patios, and pergolas
- •Flooring upgrades replacing builder carpet with LVP or hardwood
North Meridian
Established neighborhoods with homes from the 1990s and early 2000s. These homes are 20-30+ years old and ready for comprehensive updates.
Common projects in North Meridian:
- •Full kitchen renovations with layout changes
- •Primary bathroom remodels
- •Whole-home remodels bringing homes to current standards
- •Home additions for growing families
Paramount / Lochsa Falls
Mid-to-upper market subdivisions with larger homes (2,500-4,000+ sq ft). Homeowners here often pursue higher-end finishes and design-focused remodels.
Common projects in Paramount / Lochsa Falls:
- •Premium kitchen remodels with custom or semi-custom cabinetry
- •Luxury bathroom remodels with freestanding tubs and custom tile
- •Basement finishing for entertainment and living space
- •Home office additions or conversions
Permit authority: City of Meridian Building Department
Online portal: https://meridiancity.org/building
- ✓Permits required for plumbing, electrical, structural, and mechanical work
- ✓HOA approval may be required before city permits for exterior changes
- ✓Online permit portal available for application and tracking
- ✓Standard residential permit processing is typically 1-2 weeks
- ✓ADU construction follows specific zoning criteria with additional review
- ✓Impact fees apply to additions and ADUs that increase square footage
- ●Lot placement — ADU location affects privacy, natural light, utility run distances, and neighbor sight lines
- ●Ceiling height — code minimums apply, but taller ceilings (9 ft) make a small ADU feel significantly larger
- ●Storage planning — ADUs need creative storage: wall-mounted shelving, loft storage, and built-in solutions
- ●Outdoor space — a small patio, porch, or deck at the ADU entrance adds livability and curb appeal
- ●Parking — most jurisdictions require at least one off-street parking space for an ADU
- ●Rental readiness — if the ADU may be rented, plan for durable finishes, separate utility metering, and tenant-friendly design
Here are the design trends we see most often in Meridian adu builder projects:
- →White and light gray kitchen cabinets replacing dark or honey oak
- →Quartz countertops replacing outdated granite slab installations
- →Open-concept kitchen and living room conversions
- →Walk-in showers with frameless glass in primary bathrooms
- →Luxury vinyl plank flooring throughout main living areas
- →Modern farmhouse and transitional design aesthetics
- →Large kitchen islands with seating and storage
- →Outdoor living spaces — covered patios, pergolas, and fire features
Meridian's real estate market has grown dramatically, with median home values rising alongside Boise's. The city's family-friendly reputation and strong school district make it one of the most desirable markets in Idaho. Homeowners who remodel in Meridian see strong returns — updated kitchens and bathrooms are the top features buyers look for in this market.
✓Licensed general contractor with ADU-specific experience in Idaho
✓In-depth knowledge of local ADU zoning rules across Boise-area jurisdictions
✓Full architectural design and engineering included
✓Complete permitting management from application through certificate of occupancy
✓All trades licensed and insured — foundation, framing, electrical, plumbing, HVAC
✓Post-construction warranty on workmanship and installation
Do ADUs require permits and planning approval?
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.
How much does it cost to build an ADU in the Boise area?
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.
How long does it take to build an ADU?
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.
Can I rent out my ADU?
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.
How much rental income can an ADU generate in Boise?
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.
What is the maximum size for an ADU?
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.
Do I need to live on the property to have an ADU?
Owner-occupancy requirements vary by jurisdiction. Some cities require the property owner to live in either the primary home or the ADU. Others have relaxed or eliminated owner-occupancy requirements. We confirm the rules for your specific location.
Will an ADU increase my property value?
Yes. A permitted, well-constructed ADU typically adds $100,000-200,000+ to property value in the Boise area — often more than the construction cost. ADUs also make a property more attractive to buyers who value rental income potential or multigenerational living flexibility.
Are open-concept remodels common in Meridian?
Yes. Many Meridian homes built in the 1990s and early 2000s have closed-off kitchens with walls separating the kitchen from the living and dining areas. Opening these walls is one of the most popular and impactful remodeling projects in Meridian.
Do Meridian HOAs affect remodeling projects?
For interior work, HOAs are generally not involved. For exterior changes — siding, paint colors, roofing, fencing, and additions — many Meridian HOAs require pre-approval. We recommend checking your HOA guidelines before starting exterior work.
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