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ADU Construction
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ADU Construction in Spokane & North Idaho

Build a fully permitted accessory dwelling unit on your property. Detached backyard cottages, garage conversions, basement ADUs, and above-garage units. 38+ years of residential construction experience in Spokane.

Discuss Your ADU Project

Types of ADUs We Build

From detached backyard cottages to garage conversions, we build accessory dwelling units that fit your property and your goals.

Detached ADUs

Detached ADUs

Standalone backyard cottages with full kitchens, bathrooms, and private entrances

Garage Conversions to ADU

Transform your existing garage into a comfortable, code-compliant living space

Basement ADUs

Convert underused basement space into a private, fully equipped dwelling unit

Above-Garage Units

Build a complete living space above your garage without sacrificing parking

Ready to Discuss Your Project?

Call us for a free, no-obligation consultation. We'll answer your questions and help you plan your next step.

Call (509) 351-0400 or Send Us a Message →
"The craftsmanship is outstanding. They understood our vision for updating our 1920s home while preserving its historic character."
James Patterson
Browne's Addition
Historic Kitchen & Bath Renovation

ADU Features & Upgrades

Make your accessory dwelling unit comfortable, efficient, and built to last.

Separate Entrance & Privacy

Separate Entrance & Privacy

Dedicated entrances, pathways, and thoughtful landscaping so both households feel at home.

Full Kitchenette or Kitchen

Full Kitchenette or Kitchen

Custom kitchens sized for the space, with quality cabinets, countertops, and efficient appliances.

Energy Efficiency

Energy Efficiency

High-performance insulation, windows, mini-split heat pumps, and tankless water heaters to keep utility costs low.

Accessibility Features

Accessibility Features

Wide doorways, zero-threshold showers, grab bars, and single-level layouts for aging in place.

Spokane ADU Regulations & Zoning

Spokane has been updating its ADU regulations to make it easier for homeowners to build accessory dwelling units. Most residential zones now allow ADUs, but the rules around setbacks, size limits, parking, and owner-occupancy vary by zoning district. We stay current on the latest Spokane and Spokane County ADU codes so you don't have to. During your consultation, we'll walk through exactly what's allowed on your specific property and handle all the permitting.

Spokane ADU Regulations & Zoning

Why Choose Us for Your ADU Project

After 38+ years of residential construction in Spokane, we know what makes an ADU project successful.

Meticulous Planning

Meticulous Planning

We plan every detail before we touch a thing. You'll know exactly what's happening, when, and why.

One Point of Contact

One Point of Contact

You'll work directly with Jason throughout your project. No runaround, no miscommunication.

Transparent Pricing

Transparent Pricing

Detailed quotes with no hidden fees. You know exactly what you are getting and what it costs.

Respect for Your Home

Respect for Your Home

We treat your property like our own. Clean worksite, protected surfaces, and courteous crews.

ADU Construction Process

Building an accessory dwelling unit takes careful planning, local knowledge, and quality execution.

1

Property Evaluation

We assess your lot, zoning, setbacks, and utility connections to determine what type of ADU fits best.

2

Design & Permitting

Architectural plans tailored to your property, followed by permit applications and all required approvals.

3

Site Prep & Foundation

Utility connections, grading, and foundation work to set up the build properly from the start.

4

Framing & Systems

Structural framing, electrical, plumbing, HVAC, and insulation installed to code.

5

Finishing & Walkthrough

Interior finishes, fixtures, appliances, and a detailed walkthrough before we hand you the keys.

We Understand the Hesitation

An ADU is a big decision. Here's what homeowners usually want to know before they commit.

"Is my property even eligible for an ADU?"

That's the first thing we figure out together. We check your zoning, lot size, setback requirements, and utility access during a free consultation. Many Spokane homeowners are surprised to learn their property qualifies. If it doesn't work, we'll tell you upfront so you don't waste time or money.

"How much is this really going to cost?"

ADU costs vary quite a bit based on size, type, and finishes. We give you a detailed, transparent quote before any work starts. No surprises. Garage conversions are typically the most affordable option, while detached new construction costs more but adds the most value and flexibility.

"Will this disrupt my daily life?"

We get it. Construction on your own property feels invasive. For detached ADUs, most of the work happens away from your main living space. For garage conversions and basement ADUs, we stage the work carefully and keep you informed every step of the way. Daily cleanup is standard for us.

ADU FAQs

Common questions from Spokane homeowners about accessory dwelling units.

What is an ADU (accessory dwelling unit)?
An ADU is a secondary living space on a single-family residential lot. It includes its own kitchen, bathroom, sleeping area, and entrance. ADUs come in several forms: detached backyard cottages, garage conversions, basement apartments, or units built above a garage. They are fully permitted, code-compliant homes.
How much does it cost to build an ADU in Spokane?
ADU costs in Spokane typically range from $150 to $350 per square foot depending on the type and finishes. A garage conversion might start around $80,000 to $120,000, while a new detached ADU usually runs $150,000 to $300,000 or more. We provide detailed quotes so you know the real numbers for your specific project.
What is the difference between an ADU and a home addition?
A home addition expands your existing house and shares its systems (HVAC, plumbing, electrical panel). An ADU is a separate, self-contained dwelling with its own kitchen, bathroom, entrance, and often its own utility connections. ADUs can be attached or detached from the main home and can potentially be rented as independent living spaces.
Do I need a permit to build an ADU in Spokane?
Yes, ADUs require building permits in Spokane and Spokane County. You will need to meet zoning requirements, building codes, and potentially have separate utility connections. We handle the entire permitting process for you, including plan review, applications, and all required inspections.
How long does it take to build an ADU?
Plan on 4 to 8 months from design to completion for most ADU projects. Garage conversions tend to be faster (3 to 5 months), while new detached construction takes longer. Permitting timelines in Spokane can add 4 to 8 weeks, which we factor into your project schedule.
Can I rent out my ADU in Spokane?
Yes, Spokane allows ADU rentals, and many homeowners build ADUs specifically for rental income. The rental income can significantly offset your mortgage or construction costs. We recommend checking the current Spokane municipal code for any owner-occupancy requirements that may apply to your zoning district.
What are the zoning requirements for ADUs in Spokane?
Spokane allows ADUs in most residential zones. Key requirements include lot size minimums, setback distances from property lines, maximum ADU square footage (typically up to 1,000 sq ft or a percentage of the main home), and height limits. Requirements vary by zone, so we evaluate your specific property during the initial consultation.
Can I convert my garage into an ADU?
Yes, garage conversions are one of the most popular and cost-effective ADU options. We handle structural modifications, insulation, plumbing, electrical, HVAC, and interior finishing to transform your garage into a comfortable living space. You may need to provide replacement parking depending on your zoning district.
Do ADUs increase property value?
ADUs generally add significant value to a property. A well-built ADU adds usable square footage, rental income potential, and flexibility for multi-generational living. In Spokane's market, properties with ADUs are increasingly sought after by buyers looking for income potential or space for family members.
What utilities does an ADU need?
ADUs need water, sewer, electrical, and heating/cooling. Depending on the type, your ADU may share utility connections with the main house or require separate service. We evaluate the most practical and cost-effective approach for your property and handle all utility coordination.

Ready to Discuss Your Project?

Call us for a free, no-obligation consultation. We'll answer your questions and help you plan your next step.

Call (509) 351-0400 or Send Us a Message →

Ready to Start Your ADU Construction?

Call now for a free consultation. We serve Spokane, Spokane Valley, Liberty Lake, Coeur d'Alene, Post Falls, and all surrounding communities.

Call (509) 351-0400
Available Monday - Friday, 8AM - 6PM
Saturday by appointment

Or Send Us a Message

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