ADU bathrooms · Los Angeles
ADU bathrooms that work hard in a small footprint
Garage conversions, detached backyard units and junior ADUs all need a bathroom that fits a tight plan, survives years of use and doesn't fight the plumbing. We design and build them, either as a standalone scope or alongside your ADU team.
Three kinds of ADU, three different bathrooms
Accessory dwelling units have become a familiar part of Los Angeles backyards, from post-war lots in Burbank and the Valley to bungalow streets in Culver City. The bathroom inside one is small, but it has to do everything a full bathroom does, often for a tenant or a family member who will use it every day.
- Garage conversion
- The slab, the existing walls and the distance to the house's sewer line shape everything. Drains usually mean cutting and trenching the slab, and the old garage floor often slopes toward the door, which matters when you're trying to get a shower pan level.
- Detached new-build
- The cleanest starting point. Drain and vent locations can be planned before the foundation is poured, so the bathroom layout should be settled early rather than left for later in design.
- Junior ADU
- Carved out of the existing house, commonly from a bedroom or attached garage. The bathroom may tie into existing plumbing inside the home, which can shorten runs but brings the age and condition of that plumbing into play.
Layout
Planning a compact bathroom that doesn't feel compact
Most ADU bathrooms fall somewhere around the size of a hall bath or smaller. A few decisions make the biggest difference to how usable they are.
One wet wall
Lining the toilet, vanity and shower up along a single plumbing wall keeps drain and supply runs short and simplifies venting. It's often the most efficient plan, and it leaves the opposite wall free for storage or a window.
Pocket or outswing doors
An inswinging door can eat a surprising share of a small floor. A pocket door or outswing door frees that space, though pocket doors need a wall without plumbing or wiring in the pocket zone.
Shower instead of a tub
A generous walk-in shower is usually a better use of an ADU footprint than a tub, and a low or no-threshold entry makes the unit easier to live in for more people. See walk-in shower installation for the detail.
Storage that stays out of the way
A recessed medicine cabinet, a shower niche and a wall-hung vanity with drawers do more than extra shelving that sticks into the room.
For layout options at different sizes, our ADU bathroom design guide walks through plans and trade-offs.
Behind the walls
Plumbing, sewer and ventilation
The run to the sewer
A detached ADU at the back of a lot may be a long way from where the house's sewer line leaves the property. Distance, the fall available across the yard, and whether a gravity connection works all affect the plan. On some sloped or low lots, a pump system comes into the conversation. Your ADU designer or civil engineer usually determines the connection; we build the bathroom to suit it.
Water supply and hot water
Longer supply runs mean a longer wait for hot water. A dedicated water heater in the unit, often a tankless model, is common. Which one makes sense depends on the unit's gas or electric service.
Ventilation that actually vents
Small bathrooms build up humidity quickly. A properly sized exhaust fan, ducted to the outside with a short, straight run, protects the finishes. We prefer controls that keep the fan running after the shower ends, such as a humidity sensor or timer.
Slab work in conversions
Trenching a garage slab for new drains is routine but messy, and the patch has to be done right so the new floor sits flat. It's one of the reasons conversion bathrooms benefit from being planned before the rest of the interior.
Finishes chosen for long, hard use
If the unit will be rented, the bathroom needs to look good through tenant turnovers with minimal upkeep. If it's for a parent or an adult child, it may need to adapt as needs change. Either way, durability comes before novelty.
- Porcelain tile over natural stone for most surfaces: dense, stain-resistant and easy to replace a piece if needed.
- Mid-toned or slightly warm grout that doesn't show every mark; epoxy grout in the shower where the budget allows.
- Quartz or solid-surface vanity tops rather than porous stone.
- A single pressure-balancing or thermostatic shower valve with a handheld on a slide bar.
- Blocking inside the walls for future grab bars, even if none go up now.
- Water-efficient fixtures, many carrying the WaterSense label, which also keep utility costs down for whoever pays them.
- Lever handles and a comfort-height toilet, small choices that make the unit usable for more people.
For a fuller accessibility plan, see our accessible bathroom remodeling service.
How we fit in
Working with your ADU builder, or building the bathroom ourselves
ADUs come together in different ways, so we offer two arrangements.
As part of a larger ADU team
If you already have an architect, designer or general contractor for the ADU, we can take on the bathroom as a defined scope: design detailing, waterproofing, tile, glass, vanity and fixtures. We coordinate rough-in locations with their plans and schedule around their inspections.
As the bathroom scope within a conversion
For a JADU or a smaller conversion, some owners want one team to plan and build the bathroom from rough-in to finish. We'll tell you plainly where the scope needs other professionals, such as structural or civil engineering, and where it doesn't.
ADU rules are set at the state level and applied locally, and they change often. Permits, setbacks, sewer connections and utility requirements need to be confirmed with LADBS or your city's building and planning departments before design is finalized.
What shapes the cost of an ADU bathroom
The bathroom is small, but the work behind it isn't always. The distance and route to the sewer connection, slab cutting in a garage conversion, a dedicated water heater, and how much of the rough plumbing is already in place are the main variables. Finishes matter less than you'd expect in a room this size, because the tile quantity is modest. Our guide to how we price bathroom remodels explains the rest.
If you're also updating the main house, the same team can handle a full bathroom remodel there.
ADU bathroom questions
Can you build just the bathroom in my ADU?
Yes. We can scope the bathroom as a defined package within a larger ADU project, coordinating with whoever is building the rest of the unit.
Should an ADU bathroom have a tub?
Usually not. A walk-in shower uses the space better and is easier for more people to use. A tub makes sense if the unit is intended for a family with young children.
How far can an ADU be from the sewer line?
There's no single answer. It depends on the lot, the available slope and local requirements. Your ADU designer or engineer should confirm the connection route with the city early in design.
What's the most durable finish for a rental bathroom?
Porcelain tile, a quartz or solid-surface vanity top, and good grout are hard to beat. Just as important is a fan that actually clears moisture, because trapped humidity is one of the most common causes of wear in small bathrooms.
ADU bathrooms across Los Angeles
Post-war lots in Burbank and Glendale and bungalow neighborhoods in Culver City see a steady stream of backyard units. We work across our full service area.
Call us
Talk to us about your bathroom
Call and tell us what isn’t working in the room. We’ll talk through scope, materials and timing, then set up a visit to measure and see the plumbing and structure.
Call for a consultation
(213) 566-7696Open daily, 7:00 AM to 10:00 PM
- Tell us whether it’s a house, condo or ADU
- Describe which bathroom and what you’d like to change
- We arrange a visit to measure and look at the room