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Book a callThinking about converting your garage into an accessory dwelling unit (ADU)? With housing costs rising and space becoming a premium, more homeowners are exploring the benefits of transforming their garages into functional living areas. This guide will walk you through everything you need to know about maximizing space in a garage conversion ADU.
Garage conversion ADUs are becoming increasingly popular among homeowners looking to create additional living space without the hassle of constructing new buildings. These units can serve as guest houses, rental units, or even home offices. By converting an existing garage, you can make the most out of your available space while also increasing your property’s value.
A garage conversion ADU is the refurbishment of a pre-existing garage into a livable area. Unlike building a new structure, converting an existing garage can save you money and time. However, not all garages are eligible for conversion, and there are zoning, permitting, and structural requirements to consider.
Understanding the differences between garage conversions and other types of ADUs is essential for making an informed decision.
Cost Efficiency
Garage conversions generally cost less than building new structures. Since the basic framework like foundations and roofing already exists, you can save significantly on construction costs. However, if the garage structure is old or deteriorated, additional rehabilitation work might be required, increasing your expenses.
Time Savings
Permitting and building new ADUs can take months, but garage conversions often have shorter timelines. Since you’re working with an existing structure, the construction phase can be quicker, allowing you to set up your new ADU faster. A 600 sq. ft. one-bedroom ADU in California, for example, can yield between $2,500 and $3,000 in monthly income, making the time investment worthwhile.
Before starting your project, there are several factors to consider to ensure your garage is eligible for conversion:
Permits
Check if your garage is permitted and complies with local building and fire codes. Unpermitted structures or those posing health and safety risks might require additional work before conversion.
Structural Soundness
Make sure your garage’s foundation, framing, and roofing are stable. Structural elements should not be sagging or uneven. Consulting a qualified contractor can help determine if your garage is fit for conversion.
Water Damage
Inspect for water damage, which is common in older garages. A musty smell often indicates water intrusion, usually from a leaky roof. Addressing these issues may involve roof repairs and other measures.
Size Requirements
In California, the minimum size requirement for ADUs is 150 sq. ft. This means even a one-car garage could be converted, although it would be quite intimate. A two-car garage, typically around 360 sq. ft., offers more room for creating a comfortable living space.
Utility Hook-ups
Your garage must be able to connect to electricity, water, and sewage lines. An HVAC system and proper insulation are also essential for creating a habitable space.
Utility Easements
Be mindful of utility easements, areas reserved for the maintenance of utilities like power lines. Building on these areas may require special permits, adding time and complexity to your project.
After confirming that your garage meets the basic requirements, you can assess the overall viability of your project. This involves evaluating the condition of the structure, available space, and necessary upgrades.
There are various ways to structure a garage conversion ADU, each with its own benefits and considerations:
Detached Garage ADU
These stand separate from your main residence and offer more privacy. Ideal for those who want to create a rental unit or private guest house.
Attached Garage ADU
Contained within the main residence, these ADUs offer the convenience of proximity while still providing independent living space.
Junior Garage ADU
Smaller in size, Junior ADUs (JADUs) are perfect for one-car garages. They offer a compact yet functional living space, often with shared amenities.
The specific requirements for converting a garage into an ADU vary based on local zoning laws and the type of ADU you’re creating. Here’s a general overview:
Sizing
Attached garage ADUs must match the size of the original structure. Detached garages can add an extra 150 sq. ft. for entrances and exits. In some jurisdictions, detached garage ADUs can go up to 1,200 sq. ft.
Access
All ADUs must have a separate exterior entrance. Attached garage ADUs may also have a connecting interior entrance.
Sanitation
ADUs must have their own bathroom. However, JADUs can share a bathroom with the main residence.
Footprints
You can build a detached garage ADU on the footprint of a demolished garage if you match its dimensions.
Parking
ADUs converted from garages usually don’t require replacement parking, but JADUs might.
Setbacks
No additional setbacks are required if you’re not changing the garage’s footprint. If adding floor area, you cannot exceed rear and side setbacks by more than 4 ft.
Fire Safety
Fire sprinklers are generally not required unless your main residence has them. Detached garage ADUs might need fire-rated walls depending on their proximity to other structures.
Owner Occupancy
Owner occupancy requirements may vary by jurisdiction. JADU owners must live in either the JADU or the main residence.
Making the most of your garage conversion ADU involves strategic design choices:
Open Layouts
Opt for open floor plans to create a sense of spaciousness.
Multi-functional Furniture
Use furniture that serves multiple purposes, such as sofa beds or fold-out tables.
Natural Light
Maximize natural light with large windows and light-reflective colors.
Converting a garage into a livable space requires several upgrades to meet building codes:
Plumbing and Heating
Ensure your plumbing, heating, and other utilities are up to code.
Insulation
Add supportive ceiling joints for insulation and drywall.
Moisture Barrier
Install a retrofit moisture barrier between the slab and flooring.
Exterior Finishes
Update exterior finishes, especially if the garage is close to property lines.
Maintaining organization in your converted garage is crucial:
Built-in Storage
Use built-in cabinets and shelving to save space.
Declutter Regularly
Keep the area tidy by decluttering regularly.
Smart Storage Solutions
Use under-bed storage, multi-purpose furniture, and wall-mounted organizers.
The timeline for converting a garage into an ADU varies but typically takes 7-9 months. The condition of your existing structure will significantly impact the duration of the project.
If your garage is old and deteriorated, tearing it down and building anew might be more cost-effective. Although this sounds extensive, it may only add a few weeks to your project timeline.
Yes, you can convert an unused storage area above your garage into an ADU. Alternatively, you could add an entire second story, though this would require additional structural support and permits.
Garage conversion ADUs offer a practical solution for homeowners looking to maximize space and add value to their property. By understanding the requirements and options available, you can make informed decisions that best suit your needs. Ready to start your conversion project? Explore our resources and get in touch with our experts to guide you through every step.
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