DC Structures
Why ADUs Are Booming in Idaho
Idaho—home to rugged mountain ranges, serene lakes, and some of the fastest-growing metros in the nation—offers an exceptionally strong environment for ADU development. With population growth surging throughout the Treasure Valley, increasing housing shortages in cities like Boise, Meridian, and Nampa, and heightened demand for flexible, affordable living options, accessory dwelling units are becoming an increasingly popular investment for Idaho homeowners.
While Idaho does not yet have statewide ADU legislation, many cities have embraced ADU-friendly zoning to help address housing needs. Boise, for example, has allowed accessory dwelling units in multiple residential zones for years and continues to expand its housing strategy to include more flexible, compact housing options with kitchen, bedroom, and bathroom spaces.
At DC Structures, we offer precision-crafted, prefabricated ADU plans designed to thrive in Idaho’s diverse climates—from snowy mountain regions to dry high-desert landscapes. Whether you’re creating rental income, building a guest house, or supporting multigenerational living, our sustainable accessory dwelling units are built to complement Idaho’s terrain and lifestyle beautifully.
Our ADU Kits
Our prefab ADU models give Idaho homeowners a streamlined, customizable path to adding beautifully designed living space to their property. Engineered with premium materials and manufactured using precision CNC technology, our models offer exceptional durability, efficiency, practicality, and long-term performance.
Sitka
SitkaCrafted for backyard use, whether as a guest suite, artist studio, or creative workspace, our Sitka ADU Kit offers limitless flexibility within a compact framework.
Average Cost to Build an ADU in Idaho
ADU construction costs in Idaho depend on local builder rates, design complexity, climate considerations, and whether the structure is attached or detached.
Nationally, accessory dwelling units range from $60,000 to $285,000, depending on style, energy-efficient features, and finish level. In Idaho, a detached accessory dwelling unit typically costs between $140,000 and $260,000, with higher costs in areas with strong construction demand—particularly Boise and the surrounding Treasure Valley.
At DC Structures, we advise clients that turnkey ADU costs usually land between three to five times the price of their design and materials package. A $50,000 ADU kit, for example, generally results in a total project cost of $150,000 to $250,000, depending on excavation, utilities, and finish selections. For an accurate estimate tailored to your Idaho property, we encourage you to request a detailed quote.
Idaho ADUs
Permitting, Zoning & ADU Regulations in Idaho
Idaho does not have a statewide law that fully mandates accessory dwelling units in every city, but it has taken legislative steps to protect certain types of accessory dwelling units—specifically internal ADUs—from being strictly prohibited by homeowner associations. That said, local cities and counties still set their own zoning regulations for detached accessory dwelling units and broader ADU standards, meaning requirements for size, placement, height, and parking vary significantly depending on where you live.
Common ADU regulations in Idaho include:
- Zoning: Many municipalities—especially Boise, Garden City, and Ketchum—allow accessory dwelling units in single-family residential zones.
- Size Limits: Accessory dwelling units are often capped around 900 sq. ft., or a set percentage of the primary dwelling. Minimum unit sizes typically start at 300 sq. ft.
- Owner-Occupancy: Some Idaho cities require owner-occupancy in either the main home or the ADU.
- Setbacks & Height: Detached dwelling units must comply with local accessory-structure setbacks; many cities cap height around 20–25 ft.
ADU Incentives, Grants & Financing in Idaho
Idaho does not currently offer statewide ADU-specific incentives or grants. However, several initiatives and proposals are emerging for accessory dwelling unit construction, particularly in high-growth regions. Boise, for example, is exploring two ADU pilot programs to expand affordable housing options. One of these programs aims to provide financial and technical assistance to homeowners who agree to rent their accessory dwelling unit at affordable rates for ten years—a significant step toward supporting ADU development in the city. As backyard tiny homes, guest houses, and rental units continue to gain momentum nationwide, Idaho municipalities may introduce local ADU-support programs in the coming years. Our team can also connect you with Idaho lenders familiar with ADU financing and construction loans!
Best Cities & Counties to Build an ADU in Idaho
Idaho offers a diverse landscape of attractive ADU markets—from booming metros to mountain resort towns. These cities currently offer some of the strongest potential:
Boise
One of America’s fastest-growing urban areas, Boise boasts a well-established accessory dwelling unit ordinance, high rental demand, and flexible zoning throughout many neighborhoods.
Meridian & Nampa
Popular among families and young professionals, these Treasure Valley cities show increasing interest in accessory dwelling units as a solution for rental income, family housing, and property-value growth.
Ketchum & Sun Valley
With strong tourism economies, these mountain towns are ideal for guest houses, short-term rentals, caretaker housing, or seasonal workforce lodging.
From college towns to ski towns to rural acreage, Idaho provides varied and profitable opportunities for ADU architecture.
DC Structures
ADU Project Gallery
How ADUs Can Boost Property Value in Idaho
With the average Idaho home price around $465,000, accessory dwelling units offer a powerful way to increase property value and add flexible living space. Since backyard tiny homes and guest houses can raise home values by up to 30%, Idaho homeowners may see an equity increase of $140,000 or more to their house after adding a backyard unit.
Idaho’s rental market is also strong, with average statewide rents around $1,800 and significantly higher rates in Boise, Coeur d’Alene, and resort towns. Over five years, an accessory dwelling unit could generate more than $100,000 in passive income, depending on rental interest and strategy. Whether used for long-term renters, Airbnb guests, family members, or seasonal workers, accessory dwelling units offer significant financial and lifestyle benefits for Idaho homeowners.
Start Your Idaho ADU Journey
Ready to add a backyard cottage, rental unit, or guest house to your Idaho property? Whether you live in Boise, the Magic Valley, or one of Idaho’s beautiful mountain towns, our team at DC Structures is here to guide your project from concept to completion.
We provide premium prefab ADU kits, customizable floor plans, engineering support, and nationwide delivery—making it easy to build a durable, beautiful ADU tailored to your land and lifestyle.