Phoenix's Premier ADU Solution
Transform your property with a custom Accessory Dwelling Unit. From planning and permitting to design and construction, we handle it all.
Our Comprehensive ADU Services
Planning & Design
Custom ADU designs tailored to your property and needs. Our experienced architects create functional, beautiful spaces that maximize your property's potential.
Permitting & Approvals
Navigate the complex permitting process with ease. We handle all paperwork, submissions, and coordination with the city to ensure your ADU project meets all requirements.
Construction
Professional construction services from experienced builders. Our team delivers high-quality craftsmanship with attention to detail, ensuring your ADU is built to last.
Why Choose BuildPhoenixADU
Local Phoenix Expertise
We understand Phoenix's unique climate, architecture, and regulations. Our designs are specifically created for Arizona living, with features to keep your ADU cool and energy-efficient.
Permit Specialists
Our team stays up-to-date with all Phoenix ADU regulations and requirements. We streamline the permitting process, saving you time and preventing costly delays.
Custom Designs
Every property is unique. We create custom ADU designs that complement your existing home while maximizing functionality and value.
All-in-One Solution
From initial concept to final walkthrough, we handle every aspect of your ADU project, providing a seamless, stress-free experience from start to finish.
Phoenix ADU Types & Options
Detached ADUs
Standalone structures separate from your main house. Perfect for rental units, guest houses, or home offices with maximum privacy.
Attached ADUs
Connected to your existing home, these ADUs share at least one wall with the primary residence, providing convenient access while maintaining separate living spaces.
Garage Conversions
Transform your existing garage into a functional living space. A cost-effective option that makes use of your property's existing footprint.
Our Simple Process
1. Consultation
Schedule a free consultation to discuss your ADU goals, property details, and budget considerations.
2. Design
Our architects create custom designs that match your vision while adhering to Phoenix's ADU regulations.
3. Permitting
We handle all permit applications and coordinate with city officials to ensure compliance.
4. Construction
Our experienced team builds your ADU with high-quality materials and craftsmanship.
Our Phoenix ADU Projects
Ready to Build Your Phoenix ADU?
Take the first step toward expanding your property's potential and value.
Frequently Asked Questions About Phoenix ADUs
General ADU Questions
An Accessory Dwelling Unit (ADU) is a secondary housing unit on a single-family residential lot. It can be attached to the primary residence, integrated into the main house, or built as a separate structure on the same property. ADUs are also known as granny flats, in-law suites, casitas, or backyard cottages.
ADUs offer numerous benefits including added rental income, housing for family members, increased property value, flexible space for home offices or studios, and contributing to housing solutions in Phoenix. They maximize your property's potential while providing independent living spaces.
ADU costs in Phoenix typically range from $150-$300 per square foot, depending on design complexity, finishes, and site conditions. A 500 sq ft ADU might cost $75,000-$150,000, while a 1,000 sq ft ADU could range from $150,000-$300,000. Our free consultation provides customized cost estimates based on your specific project.
The typical timeline for an ADU project in Phoenix is 6-12 months from initial consultation to completion. This includes 2-3 months for design and permitting, followed by 4-9 months for construction, depending on size and complexity. Weather conditions in Phoenix can sometimes affect construction schedules.
Phoenix allows several types of ADUs (referred to as "Guest Quarters" in city code) including detached ADUs (separate structures), attached ADUs (connected to the main house), garage conversions, and basement conversions (where applicable). Each type has specific requirements and advantages depending on your property and needs.
Phoenix ADU Regulations
Yes, ADUs (referred to as "Guest Quarters" in Phoenix municipal code) are legal in Phoenix. In early 2022, the City of Phoenix approved changes to its zoning ordinance to allow more homeowners to build ADUs on their properties. The specific regulations vary depending on your property's zoning and location.
ADUs (Guest Quarters) are permitted in residential zones R1-14, R1-10, R1-8, R1-6, and R-2. Properties must meet minimum lot size requirements depending on the zone. For example, R1-6 requires a minimum lot size of 6,000 square feet.
The maximum size of an ADU in Phoenix is limited to 50% of the primary dwelling's square footage, not to exceed 1,000 square feet. Additional restrictions may apply based on specific zoning districts.
Detached ADUs must maintain minimum setbacks from property lines, typically 15-20 feet for front yards, 5-10 feet for side yards, and 10-15 feet for rear yards, depending on the zoning district. Corner lots may have different requirements.
Yes, you can rent out your ADU in Phoenix. However, there may be regulations regarding short-term rentals (less than 30 days). Additionally, some neighborhoods or HOAs may have their own restrictions on rentals. We recommend checking your specific property's zoning and any applicable HOA regulations.
Yes, Phoenix typically requires one additional off-street parking space for an ADU. This parking space must be provided on the property, not in the public right-of-way. Some properties may qualify for reduced parking requirements based on proximity to public transit or other factors.
It depends on your specific HOA's Covenants, Conditions, and Restrictions (CC&Rs). While Phoenix zoning may allow ADUs, your HOA may have additional restrictions or requirements. We recommend reviewing your HOA documents and potentially consulting with your HOA board before proceeding with an ADU project.
ADU Design & Construction
Popular ADU designs in Phoenix include Southwest contemporary, desert modern, and Spanish/Mediterranean styles. These designs typically incorporate features suited to Arizona's climate, such as appropriate roof overhangs for shade, thermal mass materials, and orientation to minimize heat gain. Our architects can design your ADU to match or complement your existing home's style.
ADUs in Phoenix can either share utilities with the main house or have separate connections. For electrical, sharing is common for smaller ADUs, while larger units may require upgraded service or separate meters. Water and sewer typically connect to existing lines, though capacity upgrades may be needed. Most ADUs use the property's existing gas service if needed.
Yes, we design our ADUs with Phoenix's climate in mind. Features include proper insulation (typically R-38 for ceilings, R-19 for walls), energy-efficient windows with appropriate SHGC ratings, desert-appropriate HVAC sizing, ceiling fans, and strategic orientation to minimize heat gain. We can also incorporate solar panels and other sustainability features.
The most common foundation for Phoenix ADUs is a concrete slab-on-grade, which works well in our soil conditions and climate. Post-tension slabs are often used to prevent cracking in our expansive soils. For areas with drainage concerns, raised foundations might be used. Our structural engineers determine the best foundation based on soil conditions and your specific site.
We design Phoenix ADUs with heat mitigation in mind, including proper orientation to minimize sun exposure, extended roof overhangs for shade, high-performance insulation, double or triple-pane low-E windows, reflective roofing materials, and appropriately sized HVAC systems. We also consider outdoor living spaces with shade structures and drought-tolerant landscaping.
ADU Planning & Permitting
Building an ADU in Phoenix requires several permits, including a building permit (which includes plan review), electrical permit, plumbing permit, and mechanical permit. You'll also need zoning approval to verify your ADU meets all requirements. Our team handles the entire permitting process, from preparation to submission and follow-up.
The permitting process for an ADU in Phoenix typically takes 6-10 weeks. This includes zoning verification, plan preparation, submission, plan review, and permit issuance. Complex projects or those requiring variances may take longer. Our team manages this process to minimize delays and address any questions from city officials.
While not strictly required by Phoenix building code, having an architect design your ADU is highly recommended. An architect ensures your ADU meets all building codes and zoning requirements, maximizes your space, creates a functional and beautiful design, and provides detailed construction documents for permitting and building. Our architectural team specializes in Phoenix ADUs.
Yes, you can build an ADU in Phoenix's historic districts, but additional approvals are required. Your design must comply with both standard ADU regulations and Historic Preservation Office guidelines. This usually means the ADU must match the architectural style of the primary residence and the neighborhood. We have experience navigating these requirements in Phoenix's historic neighborhoods.
Yes, soil testing is typically required for new construction in Phoenix. Arizona's soil can be expansive and reactive to moisture changes, which affects foundation design. A geotechnical engineer will analyze your soil's composition, expansion potential, and bearing capacity. This testing is essential for proper foundation design and typically costs $1,500-$3,000, depending on property size and complexity.
ADU Costs & Financing
Major cost factors for Phoenix ADUs include size (square footage), construction type (detached vs. attached), foundation requirements based on soil conditions, finishes and materials quality, site conditions (slope, access, existing utilities), HVAC systems designed for our climate, and current construction material costs. Labor costs in the Phoenix market also impact the total project budget.
Yes, there are several financing options for ADUs in Phoenix including home equity loans, home equity lines of credit (HELOCs), cash-out refinancing, construction loans, renovation loans like Fannie Mae's HomeStyle Renovation loan or FHA 203(k) loans, and personal loans. Some lenders offer specific ADU loan products that consider the future rental income potential of your ADU.
Yes, you can finance both a home purchase and ADU construction with certain mortgage products. Renovation loans like Fannie Mae's HomeStyle or FHA 203(k) allow you to include planned ADU construction costs in your initial mortgage. For new construction, some construction-to-permanent loans can include ADU building costs. These options allow you to finance both the home and ADU with one loan.
Yes, adding an ADU will typically increase your property taxes in Phoenix, as it increases your property's assessed value. The specific amount depends on the ADU's size, quality, and features. In Maricopa County, the property tax rate is approximately 1% of assessed value. Our team can provide a rough estimate of potential tax impacts during your consultation.
ADUs in Phoenix typically offer a strong ROI through increased property value and potential rental income. Property value increases often range from 20-30% of the ADU's construction cost. For rental income, Phoenix ADUs typically yield 8-12% annual returns, with monthly rents ranging from $1,000-$2,000 depending on size, location, and amenities. ADUs can often pay for themselves within 7-10 years through rental income.
ADU Uses & Benefits
Yes, you can use your ADU for short-term rentals in Phoenix, but specific regulations apply. Arizona state law (SB 1350) prevents cities from banning short-term rentals, but Phoenix requires registration, business licensing, and tax collection. Properties must comply with noise ordinances, parking requirements, and occupancy limits. Some HOAs may have additional restrictions on short-term rentals.
ADUs are ideal for multigenerational living in Phoenix, providing privacy and independence while maintaining proximity. They typically include separate entrances, full kitchens, bathrooms, living areas, and bedrooms. For aging parents or family members with mobility concerns, we design accessible ADUs with features like zero-step entries, wider doorways, and grab bars. This arrangement offers support while respecting everyone's independence.
Absolutely! ADUs make excellent home offices or studios in Phoenix. They provide separation from household distractions while eliminating commutes. For home offices, we can design custom workspaces with proper lighting, built-in storage, and technology integration. For art studios, we consider natural lighting, ventilation, utility sinks, and specialized storage. These spaces can later convert to rental units if your needs change.
In Phoenix, ADUs typically rent for $1.50-$2.50 per square foot monthly, depending on location, amenities, and quality. A 500 sq ft ADU might rent for $750-$1,250/month, while a 1,000 sq ft unit could bring $1,500-$2,500/month. Premium locations near downtown, Scottsdale, or near major employers can command higher rents. During your consultation, we can provide a customized rental analysis based on your specific location.
Yes, an ADU significantly increases property value in Phoenix. Typically, you can expect a 20-30% return on your investment in terms of property value increase. For example, a $150,000 ADU might add $30,000-$45,000 in immediate property value. Long-term appreciation is even greater as Phoenix's housing market continues to grow and the demand for rental units increases.
Construction Process
Construction impact varies based on ADU type and location. Detached ADUs cause minimal disruption to the main house, while attached ADUs or conversions can be more intrusive. Typical disruptions include noise during work hours (usually 7am-4pm weekdays), construction vehicles, temporary utility interruptions, and dust (which we minimize with containment procedures). Phoenix's dry climate helps limit mud issues common in other regions.
Our team coordinates all utility connections for your ADU. For electrical, we work with SRP or APS to determine if your existing service needs upgrading or if separate meters are required. For water and sewer, we coordinate with the City of Phoenix Water Services Department. Gas connections (if needed) are arranged with Southwest Gas. We handle all necessary permits, inspections, and coordination with utility companies.
We adapt our construction schedule to Phoenix's climate, starting earlier in the day during summer months (often 5-6am) and scheduling temperature-sensitive tasks (like concrete pours) during cooler periods. Our teams use cooling stations, shade structures, and hydration protocols. For materials, we provide proper storage to prevent heat damage and use techniques appropriate for high-temperature installation.
For Phoenix ADUs, we typically recommend high-efficiency mini-split heat pump systems, which provide both cooling and heating. These systems work well in our climate, are energy-efficient, and don't require extensive ductwork. For larger ADUs, properly sized conventional HVAC systems with appropriate SEER ratings for desert conditions may be used. We also often incorporate ceiling fans and proper insulation to enhance efficiency.
We maintain high quality through rigorous oversight including regular inspections by our project managers (beyond required city inspections), detailed scope documents for all subcontractors, climate-appropriate construction techniques, materials selected for Phoenix's environment, and systematic quality checks throughout the project. We also provide a comprehensive warranty on our work and maintain open communication throughout the construction process.
Legal & Regulatory Questions
You can build an ADU on a property with easements, but the ADU structure cannot be located within the easement area without special permission. Utility easements, which are common in Phoenix, restrict building on portions of your property where utilities have access rights. During our initial assessment, we'll identify all easements on your property and design your ADU accordingly to avoid these areas.
Phoenix ADUs must comply with the 2018 International Residential Code (as adopted by Phoenix), 2017 National Electrical Code, 2018 International Energy Conservation Code, 2018 International Plumbing Code, 2018 International Mechanical Code, and Phoenix Amendments to these codes. Additionally, your ADU must meet Phoenix's zoning requirements for Guest Quarters. Our team stays current with all applicable codes.
Yes, if you plan to rent out your ADU in Phoenix, you need a Transaction Privilege Tax (TPT) license from the Arizona Department of Revenue and may need to register with the City of Phoenix. For short-term rentals, additional requirements apply, including registration with the county assessor. We can provide guidance on these requirements during your consultation.
Phoenix doesn't impose restrictions on who can live in your ADU. You can house family members, rent to tenants, or use the space for short-term rentals (subject to applicable regulations). Some older neighborhood CCRs might contain language restricting rentals, but these are increasingly unenforceable. Unlike some cities, Phoenix doesn't currently require owner occupancy of either the main house or ADU.
If your property doesn't meet Phoenix's standard ADU requirements (such as lot size or setbacks), you may be able to request a variance from the city. This process involves demonstrating why the standard regulations create a hardship for your specific property. Alternatively, we can help design a modified ADU that does comply with existing regulations. During your consultation, we'll evaluate your options based on your property's specific circumstances.
Property Considerations
Yes, ADUs can be built on sloped lots in Phoenix, though they require specialized design and construction approaches. Depending on the slope severity, options include step-down foundations, retaining walls, or partially elevated structures. While sloped lots present challenges, they can also create opportunities for interesting multi-level designs or tucked-under garages. Construction costs typically increase 10-30% compared to flat lots due to additional site work and foundation requirements.
Property suitability for an ADU depends on several factors including zoning compliance, lot size (typically minimum 6,000-14,000 sq ft depending on zone), available space meeting setback requirements, access for construction and future use, utility service capacity, soil conditions, and any easements or restrictions. During our free consultation, we conduct a comprehensive property assessment to determine feasibility and identify the best ADU options for your specific site.
Optimal ADU locations in Phoenix typically include backyards (providing privacy for both structures), side yards with adequate width, over existing garages (for second-story ADUs), or attached to the main house where appropriate connections exist. We consider factors like solar orientation (to minimize heat gain), existing trees and landscaping, access points, utility connection locations, and your specific privacy preferences when recommending placement.
Many Phoenix properties will need electrical service upgrades when adding an ADU. Typical Phoenix homes have 100-200 amp service, and adding an ADU often requires upgrading to 200-400 amps, depending on the ADU size and electrical needs. During our assessment, we evaluate your current service capacity and coordinate with SRP or APS if upgrades are needed. These upgrades typically cost $2,500-$7,500 depending on complexity.
ADUs can coexist with swimming pools and other backyard features with proper planning. We design around existing pools, considering required access setbacks (typically 3-5 feet) and ensuring safety compliance. Sometimes pools may need modest resizing or reshaping to accommodate an ADU while maintaining proper function and aesthetics. For properties with elaborate landscaping, we create plans to preserve key features or transplant valuable plants where possible.