One of the quickest and cheapest ways to add living space or rental income to your property is to turn your garage into an ADU (Accessory Dwelling Unit). However, it’s more than just painting and putting in new floors. Structural problems like foundations, framing, roof loads, lateral resistance, and mechanical penetrations are often the things that keep permits from being approved and a building that is safe and up to code.
Most garages weren’t built to meet residential standards, so they often need structural upgrades. Problems like weak foundations, bad framing, or missing lateral support can quickly get in the way of getting a permit. Planning for these needs ahead of time makes the approval process go more smoothly and makes the ADU safer and more durable.
From Garage to ADU: What You Need to Know
In the sections below, we’ll go over the most important structural factors to think about when turning a garage into an ADU and point out professional services that can help homeowners through this process.
The article starts with a detailed look at ProStruct Engineering, including how it works and what it offers. Then we will talk about a few other service providers that offer similar support on a smaller scale. We’ll also discuss common structural needs, what to expect when it comes to permits, to help you get ready for your garage-to-ADU conversion.
#1: ProStruct Engineering: Engineering Confidence for ADU Conversions
ProStruct Engineering is a national residential structural engineering company that specializes in full-service structural permit sets for custom homes, additions, and ADUs, such as garage conversions. They have quick turnaround times and a “permit-ready” approach that helps builders and homeowners get their permits in quickly.
Why Choose ProStruct?
They focus on making structural plans for homes and ADUs, and they offer special ADU services like site visits, structural calculations, and stamped permit sets. That specialization makes the review process faster and lowers the risk of rework.
Main Features
- Structural drawings that are ready for permits involve foundation plans, framing plans, sections, connection details, and structural notes that are the proper size for local codes. A licensed PE in the area where you build will stamp these drawings.
- Site inspection and feasibility checks usually start with a review of the site or garage to find any potential issues, such as the condition of the slab, the size of the beams, the location of existing lateral systems, and the location of utility penetrations. This helps keep things from going wrong when demolition begins.
- Retrofit options for converting slab garages if the current slab or foundation isn’t strong enough, ProStruct will suggest under-pinning, new footings, or engineered slab repairs, and show you how to connect the new ADU structure to the existing framing.
- Lateral-force upgrades explain the shear walls, hold-downs, and diaphragms that are needed when changing the loads on the roof or second floor or adding living space to a garage that wasn’t originally meant for living.
- Permit guarantee and quick turnaround talks about how quickly they can get things done, and how they work to avoid plan check rejections.
ProStruct is a great first stop if you want a dedicated residential structural firm that provides stamped, permit-ready ADU/garage conversion drawings and focuses on predictable pricing and quick turnaround.
#2: SnapADU
SnapADU is a full-service ADU company that handles both design and construction, primarily in California. They create architectural plans, structural engineering, Title-24 compliance, and permits, making it convenient if you prefer one company to manage all the details.
Main Features
- ADU designs that are standard but can be changed. They use tried-and-true layouts that can be changed to fit the size of the garage and the conditions of the site.
- Coordination of structural engineering makes sure that framing, foundation upgrades, and load requirements are all included in the design from the beginning.
- Help with permits and following the code by which homeowners get through the local approval process, which cuts down on delays and changes that come up unexpectedly.
- Full project management keeps things going from the early planning stages to the paperwork needed for permits.
SnapADU is a strong choice if you want one team to handle both the design and structural work for a garage conversion. Their coordinated approach helps align layouts, engineering needs, and permits, smoothing the path to approval and construction.
#3: Better Place Design & Build
Better Place is a local design-build ADU firm that works on full ADU projects, from design to permitting to construction. They provide advice on how much an ADU will cost and an estimator/calculator that is useful for garage conversions.
Main Features
- The integration of design and engineering in one place aligns architectural plans with structural needs early on, which cuts down on changes that need to be made during permitting and construction.
- Assessment of the garage’s feasibility checks the current state of the garage to find out what structural problems there are and what upgrades are needed before making detailed plans.
- Documents that focus on permits make drawings and other documents that meet the requirements of the local building department.
- Solutions that are ready for construction help make sure that structural details go smoothly from the design phase to the construction phase.
Better Place Design & Build uses a design-build approach that prioritizes construction efficiency, clarity, and compliance to assist individuals in converting their garages into ADUs. By combining structural coordination, architectural planning, and permitting guidance into one package, they simplify the conversion process.
Conclusion
To turn a garage into an ADU, you need to do more than just change the layout. You also need to make sure that the space meets structural and code requirements that make it safe, long-lasting, and acceptable to local authorities.
Early structural planning is very important for a successful conversion. Working with professionals who know what they’re doing and making sure that all the paperwork is ready for permits from the start can speed up approvals, cut down on revisions, and help turn an existing garage into a fully compliant and livable home.
With a Master’s in Architecture from the University of California, Berkeley, Alexander Martin has dedicated the last 18 years to enhancing outdoor living through thoughtful and robust structure design. His career kicked off in urban planning, giving him a unique perspective on integrating structures into diverse environments. In 2019, Alexander brought his expertise to our website, offering insights into creating versatile outdoor spaces. Since then, he has been the lead advisor for our outdoor design projects and is known for his ability to merge functionality with environmental consciousness. Alexander enjoys rock climbing outside of work and participates in community development projects, activities that reflect his passion for the outdoors and sustainable design.
