How Much Does It Cost to Build an ADU?

ADU PLANS GARAGE CONVERSION PLANS DETACHED ADU PLANS ADU PORTFOLIO ADU BLOG ADU PLANS GARAGE CONVERSION PLANS DETACHED ADU PLANS ADU PORTFOLIO ADU BLOG SCHEDULE A FREE CONSULTATION How Much Does It Cost to Build an ADU? December 18, 2024 How much does an ADU cost? That is inevitably the first question you’ll ask when considering a new ADU. I do not blame you; that would be the first question I would ask as well. There is no reason to spend time and money designing and planning an ADU that is going to be too expensive to build, or too expensive to afford. An ADU will cost anywhere between $100,000 and $350,000+ depending on the size and design of the ADU. The final ADU cost is determined by factors such as the type of ADU being built (Attached vs Detached vs Garage Conversion), the accessibility of the building site, and the quality of material specified. And with cost in mind I thought I’d take a few minutes and help you understand a typical ADU budget, and even provide a real world cost breakdown for a custom detached ADU I recently built in the City of Los Angeles. Keep in mind that all construction projects are unique, and cost will vary depending on the size of ADU you want to build and the quality of construction you desire. ADU Construction Cost Budget The following cost breakdown is for a 650 sqft detached ADU. This small backyard home is what I would describe as custom with many nice upgrades. The building was designed to be ultra-efficient with an air-tight building envelope and insulation well above code requirement. Upgrades like rift white oak kitchen cabinets and vaulted ceilings in the main living area added to the build cost but gave the finished ADU a very luxurious feel. The details that follow are for a new detached custom ADU in or around Los Angeles. It covers everything from initial design and planning, to city permits, to hard construction costs and issuance of the Certificate of Occupancy (CofO). Line Item Cost Comments: Design & Structural Engineering $12,000 The budget included design fees to DNA Drafting for the ADU Design and Structural Engineering. Fees also covered energy modeling per State of California Title 24 requirements, and a storm water drainage plan by the Civil Engineer. Building Permits $8,500 All fees required to plan and build the ADU through the City of Los Angeles. Fees included Los Angeles Department of Building and Safety ($), City of Los Angeles Fire Department to verify there was a fire hydrant close by ($), City of Los Angles Bureau of Engineering ($), and City of Los Angeles Storm water ($). Site Prep / Excavation $7,000 ADU was built in a backyard that was almost completely flat and required no demolition of any existing structures and very little site prep. This fee covered the trenching on the foundation footings and preparation of the building pad. Also included the hauling of the spoils (i.e. – dirt) that were removed when we trenched the footings. Site Drainage System & Rain Harvesting $9,000 All new construction in Los Angeles requires that any rain that falls on the roof (or other impermeable structures) must be retained on-site and treated. This requires rain barrels to collect all roof run-off and a filtration system to treat the rainwater before it is used for landscaping on sent to the city storm drain. Concrete Foundation $19,500 Our Structural Engineer designed a slab-on-grade foundation for the ADU due to the flatness of the backyard. Our footings were in expansive soil so they needed to be a little deeper than usual, but overall the foundation was relatively inexpensive and easy to build. Rough Carpentry $26,000 Standard 2×6 walls and 2×12 roof joists were used and the amount of structural beams were kept to a minimum to keep the costs of the rough framing relatively low. Stucco $14,500 A smooth “Santa Barbara” stucco siding finish was used on the exterior which gives the home a modern, luxurious feel. Roofing $12,000 A high quality asphalt shingle “cool roof” was installed to match the roof of the existing home. The roof comes with a 30 year warranty and looks fantastic!. Windows & Exterior Doors $9,500 We used Milgard Ultra Series fiberglass casement windows throughout the ADU. The fiberglass windows are a great choice for durability and longevity. Plumbing $24,600 This covered all the rough and finish plumbing and plumbing fixtures for the ADU, but it also included connecting the ADU to the city sewer and taping into the city fresh water lines. Electrical $21,500 The ADU is set-up with its own electrical meter and panel, so the ADU can be rented and the renter can pay for their energy usage separately from the main house. Due to the age of the existing electrical panel on the front house the city required that we upgrade the existing panel as part of the project which added money to our budget for electrical. HVAC $7,200 A super-efficient mini split HVAC system was designed and installed for the ADU. Insulation $8,500 The Title 24 requirement for energy efficiency are already pretty high in the State of California, but we decided to increase the efficiency of our ADU even more by adding 2″ of continuous insulation to the exterior of the walls and roof. This additional insulation cost a little more but will improve the comfort in the ADU substantially. Drywall & Interior Paint $11,500 A Level 5 drywall finish was applied to interior walls of the ADU. A Level 5 finish (for those of you unaware) is a full skim coat finish which gives the walls a completely smooth finish. It is the highest level of finish available and gives the ADU a luxurious wall finish. Interior Doors $3,800 Solid wood interior doors were used throughout the ADU. In such a small home it is important to use solid wood to reduce sound transfer and noise throughout the
ADU Design Ideas: Maximizing Space and Style

ADU PLANS GARAGE CONVERSION PLANS DETACHED ADU PLANS ADU PORTFOLIO ADU BLOG ADU PLANS GARAGE CONVERSION PLANS DETACHED ADU PLANS ADU PORTFOLIO ADU BLOG SCHEDULE A FREE CONSULTATION ADU Design Ideas: Maximizing Space and Style December 18, 2024 Accessory Dwelling Units (ADUs) have become increasingly popular as homeowners seek to maximize their property’s potential, create additional income streams, or provide housing for family members. The versatility of ADUs allows for a wide range of design possibilities, from creating a cozy rental space to a comfortable home for family members. Designing an ADU involves thoughtful planning and creativity to maximize the available space. Whether you’re looking for ADU design ideas, ADU interior design inspiration, or practical tips for planning an ADU, this guide will cover all the essentials to help you create a functional and beautiful space. Understanding ADU Basics Before diving into specific ADU design ideas, it’s essential to understand what an ADU is and the types available. An ADU is a secondary housing unit on a single-family residential lot. The main types of ADUs include: Detached ADUs: Standalone units separate from the main house. Attached ADUs: Units that are attached to the main house. Garage Conversions: Transforming an existing garage into a livable space. Basement Conversions: Utilizing the basement area as an ADU. Internal ADUs: Created within the main house, such as attic conversions. Each type of ADU has its own design challenges and opportunities, which we will explore in detail. ADU Design Principles When designing an ADU, there are several key principles to keep in mind: Maximizing Space: ADUs are typically smaller than the main house, so efficient use of space is crucial. Functionality: Every square foot should serve a purpose. Multifunctional furniture and intelligent storage solutions can help achieve this. Natural Light: Incorporating large windows and skylights can make the space feel larger and more inviting. Privacy: Ensure the ADU offers enough privacy for its occupants, primarily if it’s intended for rental purposes. ADU Interior Design Ideas Open Floor Plans One of the most effective ADU design ideas is an open floor plan. This creates a sense of spaciousness and allows for flexible furniture arrangements. Consider combining the living, dining, and kitchen areas into a cohesive space. Smart Storage Solutions Incorporate built-in storage options to keep the space clutter-free. Custom cabinetry, under-bed storage, and wall-mounted shelves are excellent ways to maximize storage without compromising style. Multifunctional Furniture Furniture that serves multiple purposes is ideal for ADUs. Examples include sofa beds, fold-out tables, and ottomans with hidden storage. These pieces can help you make the most of limited space. Compact Kitchens Design a kitchen that is both functional and space-efficient. Use compact appliances and vertical storage solutions, and consider a U-shaped or L-shaped layout to optimize workflow. Lofted Sleeping Areas If the ceiling height allows, a lofted sleeping area can free up valuable floor space. This is an excellent option for studio or small ADUs where every inch counts. Use of Mirrors Mirrors can make a small space feel larger and brighter. Consider placing mirrors opposite windows to reflect natural light and create an illusion of depth. Neutral Color Palettes Light, neutral colors can make a space feel more open and airy. Shades of white, beige, and light gray are excellent choices for walls, while pops of color can be added through accessories and artwork. Backyard ADU Ideas Outdoor Living Spaces Extend the living space of your ADU by creating a comfortable outdoor area. A small patio, deck, or garden can provide a relaxing retreat for residents. Landscaping for Privacy Use landscaping to create a sense of privacy around the ADU. Hedges, fences, and strategically placed plants can shield the unit from the main house and neighboring properties. Green Roofs and Walls Incorporating green roofs or living walls can enhance the aesthetic appeal of your ADU and contribute to sustainability. These features also help with insulation and can reduce energy costs. Eco-Friendly Design Consider incorporating eco-friendly design elements such as solar panels, rainwater harvesting systems, and energy-efficient appliances. These features not only reduce the environmental impact but also attract eco-conscious renters. Small ADU Ideas Vertical Space Utilization When floor space is limited, think vertically. Tall shelves, hanging storage, and lofted areas can provide additional space without expanding the unit’s footprint. Sliding Doors Sliding doors, including pocket and barn doors, save space compared to traditional swinging doors. They are handy in tight spaces like bathrooms and closets. Minimalist Design A minimalist design approach can make a small ADU feel larger. Focus on essential furniture pieces and simple decor, and avoid over-cluttering the space. Large Windows Large windows can make a small ADU feel more spacious by bringing in natural light and offering views of the outdoors. Consider floor-to-ceiling windows or sliding glass doors to maximize light. ADU Interior Design Ideas for Specific Rooms Living Room Multipurpose Furniture: Use furniture that doubles as storage or converts for different uses. Accent Walls: Create a focal point with an accent wall using paint, wallpaper, or textured materials. Kitchen Compact Appliances: Choose smaller, space-saving appliances without compromising functionality. Efficient Layout: Ensure the kitchen layout follows the work triangle principle for optimal efficiency. Bathroom Walk-In Showers: Walk-in showers take up less space than traditional tubs and are easier to clean. Floating Vanities: Floating vanities create the illusion of more space and provide additional storage options. Bedroom Under-Bed Storage: Utilize the space under the bed for storage bins or drawers. Murphy Beds: Murphy beds can be folded away when not in use, freeing up valuable floor space. Conclusion Designing an ADU requires creativity and careful planning to ensure the space is functional and aesthetically pleasing. By following these ADU design ideas, you can create a small, efficient living space that feels spacious and comfortable. Whether designing a detached ADU, converting a garage, or creating an internal ADU within your home, these tips and ideas will help you make the most of every square foot. Remember, the key to successful ADU design is
ADU Garage Conversion 101

ADU PLANS GARAGE CONVERSION PLANS DETACHED ADU PLANS ADU PORTFOLIO ADU BLOG ADU PLANS GARAGE CONVERSION PLANS DETACHED ADU PLANS ADU PORTFOLIO ADU BLOG SCHEDULE A FREE CONSULTATION ADU Garage Conversion 101 December 18, 2024 Is it legal to convert my garage into an ADU? Yes, if you own a single-family home anywhere in California with residential zoning you can build a Garage Conversion ADU. Each city and county have slightly different requirements for converting your garage into an ADU. Still, thanks to laws passed by the State of California, as of January 2017, every California homeowner can convert their attached or detached garage into a livable, rentable dwelling unit. What is a Garage Conversion ADU? Los Angeles City Ordinance No. 186481 dictates what an ADU is and where you can build one. The definition of an ADU as described by the City of LA states, Los Angeles City Ordinance No. 186481 ACCESSORY DWELLING UNIT (ADU). An attached or detached residential dwelling unit provides complete independent living facilities for one or more persons and is located on a lot with a proposed or existing primary residence. It shall include permanent provisions for living, sleeping, eating, cooking, and sanitation on the same lot as the single-family or multifamily dwelling is or will be situated. ADUs include efficiency units as defined in Section 17958.1 of the Health and Safety Code, manufactured homes as defined in Section 18007 of the Health and Safety Code, and Movable Tiny Houses. Should I convert my garage? This is not a simple yes or no question. Whether or not you should convert your garage into a rental depends on many factors, and all homeowners will have their unique motivation for considering a garage conversion. When building a rental unit, guest home, or home office, you must thoughtfully weigh the pros and cons to decide which ADU type is best for you, your property, and your lifestyle. Garage Conversion vs. New Construction ADU Many homeowners consider the advantages and disadvantages of converting their garage vs. building a new ADU somewhere else on their property. There are two main advantages for converting a garage vs. building a new stand-alone ADU. Garage Conversion Advantages Construction Cost The price for a garage conversion ADU is substantially less expensive than a new detached or attached ADU. Since the garage already exists, a conversion saves money on the foundation, framing, and roofing portions of the construction project. Time Savings A garage conversion is typically quicker to permit, and the construction timeline is much faster than building a new unit from scratch. But in addition to the advantages, there are also disadvantages that you must consider. Disadvantages of Converting Your Garage Loss of garage space for parking You are not required to replace the parking you lose when you convert your garage. But, when the garage conversion is complete, you will have less covered parking on your property or less storage if you do not park cars in your garage. This lack of parking and storage could be a turn-off for potential buyers. Lower Return on Investment (ROI) vs New Construction When you convert your garage to an ADU, you increase the property value in most instances because you add habitable square footage to the overall property. And since single-family homes are appraised based on the home’s characteristics and the useable square footage, the ADU will increase the property’s value. But the other side of the coin is that you are converting your garage, which is a valuable amenity in California. A loss of a standard two-car garage will most likely decrease your home’s value, offsetting some of the property value increase you gain with the new ADU’s addition. You will need to evaluate whether your garage’s loss is a big deal and how it might affect your property’s desirability for a future owner. How much does it cost to convert my garage into an ADU? Most garage conversions cost between $100,000 and $165,000. The size of the garage conversion, the location and access of the existing utilities, and the quality of the finish materials will influence the final price. As examples, we can look at three different garage conversion projects and the approximate cost of each. Straight Garage Conversion – Modest and SimpleEstimated budget $100,000+ The fastest and least expensive garage conversion type is to leave the existing garage structure 100% intact. This means no additional square footage added and no changes to the overall structure of the garage. In this scenario, you would add an efficiency kitchen, small ¾ bathroom, mini-split HVAC system for heating and cooling, and bring the electrical up to code for a living unit. Additionally, building finish materials would be modest and simple (i.e., No designer plumbing fixtures or fancy kitchen cabinets and countertops). A project like this will end with a nice, clean ADU that will be safe and livable but without any bells and whistles. High-End Garage Conversion – Structural and Architectural UpgradesEstimated budget $150,000+ You may find that a straight garage conversion is not exactly what you need. Maybe your garage is old and needs structural upgrades. Or perhaps you want to create vaulted/lofted ceilings or a small addition to make the ADU feel larger. In this scenario, the ADU would have a larger kitchen and a full bathroom. The electrical and gas services will be individually metered so that the ADU will be billed separately for utilities. And your contractor will alter the roof structure to create a lofted/vaulted ceiling. A project with this budget will feel like a small custom home, and the interiors will feel larger and more luxurious. A separate bedroom area adds privacy to the conversion. 2-Story ADU Garage Conversion – Full Custom RebuildEstimated budget $280,000+ The next and final level of ADU garage conversion is the fully custom rebuild. The rebuild will include the demolition of the existing garage, and the rebuild will consist of a much larger floorplan and a 2nd story addition. In this scenario, the owner