Tankless Water Heater Swap and Unpermitted Garage Bathroom
An owner-occupied 1952 single-family house in Van Nuys has a 40-gallon atmospheric gas water heater in the attached garage. The homeowner wants to replace it with a 199,000 Btu/h condensing tankless unit, move it 8 ft along the garage wall, add a recirculation loop, and reuse the existing 1/2-inch gas stub. The same homeowner also wants to keep a bathroom added in the converted garage eight years ago without a permit; the work included a toilet, lavatory, shower, and a 2-inch drain tied into the house sewer. The contractor says the tankless swap is 'like-for-like' and needs no permit, that the old bathroom can be handled with an as-built letter, and that the existing single-wall metal vent can be reused because the garage is open. The house has a 100-amp panel, and the tankless unit requires a 120-volt circuit. The homeowner is the occupant and is not a licensed contractor.
1. Does this work require permits, and who may obtain them? Explain the permit and licensing issues.
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Permits are required. A water heater replacement is not exempt simply because the Btu input is similar; the tankless unit is a different appliance with new venting, condensate, gas sizing, electrical, and clearance requirements. LADBS plumbing and electrical permits are required, and if gas piping is altered, a gas pressure test and inspection are required. The owner-occupant of a single-family house may be able to obtain owner-builder permits, but the work must be done by the owner or a licensed contractor. A handyman cannot pull the permit or perform work over the California $500 threshold. The application must identify the appliance, vent termination, gas input, and electrical circuit. The recirculation loop is new piping and must be permitted and tested. The garage bathroom is separate unpermitted construction; it cannot be legalized by letter. It requires a permit, plans or an accepted as-built, inspection of the drain, vent, water, and electrical, and fees or penalties. Concealing it is not an option.
2. List the technical issues that must be resolved before the tankless unit can pass plan review and inspection.
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Before approval, check: (1) gas capacity: 199,000 Btu/h through a 1/2-inch stub is almost certainly undersized; use the gas sizing tables with developed length and pressure drop, and likely upgrade to 3/4 inch or larger; (2) venting: a condensing tankless unit requires the manufacturer-listed PVC, CPVC, or PP vent, not single-wall metal, with proper termination clearances; (3) condensate: neutralize and drain per manufacturer; (4) combustion air and clearances from garage storage; (5) seismic anchorage and a listed flexible gas connector; (6) electrical: dedicated 120-volt circuit, GFCI where required, and 100-amp panel capacity; (7) water heater pan and drain, relief valve, and expansion control if the system is closed; (8) recirculation pump and check valve; (9) Title 24 and permit fees. Inspections will include rough gas pressure test, vent, electrical, and final.
3. How should the unpermitted bathroom be handled, and what are the risks if it is left as is?
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Treat it as a violation. The owner should file for a permit to legalize or remove it. LADBS may require plans showing the existing bathroom, drain size, vent, and structural work. Inspectors may open walls or slab to verify the 2-inch drain, slope, trap, vent, and connection. If the drain is undersized or improperly vented, it must be corrected. The owner should not cover work before inspection. The fact that the work is eight years old does not make it code-compliant; disclosure and correction are needed. City records or a title report may show no permit. The contractor's as-built letter is not a substitute for inspection. Leaving it can create resale, insurance, and enforcement problems.