digest
Short Summary
Main recommendation: To build an affordable ADU over a garage, use a super simple design, self-manage the project, and do as much of the work yourself as possible. The speaker, Derek, says he built this 22 by 26 foot unit with a two-car garage for $65,000, largely by doing the work himself.
Key Points
- Keep the design simple: a one-wall galley kitchen, a basic bathroom, and recessed lighting, with no L-shaped kitchen or island that would eat into living space.
- Use an exterior staircase instead of an interior one, which preserves square footage inside the small unit.
- Tuck exterior components such as the gas meter, on-demand water heater, and heat pump unit to the back of the building, out of sight from the entry.
- Finish the garage below as a mixed-use space with insulated walls, drywall, a soundproofed ceiling, and a mini-split HVAC for temporary office or storage use.
- Use a private digital meter, reading it monthly and billing the tenant only for their kilowatt-hour usage, rather than installing a separate public meter.
Details Worth Noting
- Concrete instructions:
- Staircase: build with 2x12 pressure-treated stringers and 2x12 cedar deck treads.
- Grab rail: use 1-1/4-inch wall tubing for the handrail, and for the railing infill, cut livestock wire on grade with bolt cutters, staple it to the back of 2x4 cedar pieces, cap with 2x6 cedar, and finish with an oil-based paint to match the PT posts.
- Toe kicks: reuse recycled fence boards.
- Kitchen countertop: buy a single granite slab (the speaker says about a couple hundred dollars), cut and tool it yourself with a skill saw and garden hose using a diamond blade, and install an overmount sink.
- Kitchen package: clear alder shaker-style cabinets, a 24-inch dishwasher, a 24-inch deep stainless overmount sink, a 24-inch apartment-size stove, a 10.1 cubic foot apartment-size fridge, and a 30-inch microwave with an exterior-venting hood.
- Bathroom tenant-proofing: use 3/4-inch pipe for towel bars and the toilet paper and hand towel holders, backed by 2x6 blocking inside the wall.
- Flooring: use hardwood in the unit for property management durability and a real slate floor in the bathroom; use LVP flooring if doing it yourself.
- The unit has a nearly 12-foot vaulted ceiling, and large windows on the south and west walls to bring in light.
- The bedroom is 10 by 12 feet, with an in-unit washer and dryer, and a loft for storage.
- Include tenant storage if the tenant lacks garage access, such as shelving or totes.
- The speaker notes that his figure is somewhat skewed because he is a builder who does much of the work himself.
Bottom Line
The speaker's cost savings come mainly from minimizing design complexity and doing labor yourself, with specific tactics such as self-cut granite, reused materials, and simple exterior-mounted systems.
