--- title: Propane for ADUs, Shops and Garages | American River Gas url: https://americanrivergas.com/guides/propane-for-adus-shops-and-garages/ business: American River Gas Co., Inc. phone: (530) 888-7438 address: 10290 Ophir Rd, Newcastle, CA 95658 hours: Monday-Friday 8:00 AM-4:30 PM (closed noon-1:00 PM) updated: 2026-10-28 --- Buying, building & moving # Propane for ADUs, shops and garages An ADU, shop or garage can run on propane either from a gas line off your existing tank or from its own tank, and the right choice depends on the total load of every appliance on the property, the size of the tank you already have, and where a new building sits relative to tank setbacks. Plan it before the foundation is poured: add up the appliance ratings, keep propane appliances out of pits and below-grade spaces, keep flammable vapors away from burners, and bring in your propane company and building department early. [Call (530) 888-7438](tel:+15308887438)[Open an account](https://americanrivergas.com/open-an-account/) ## Start with the load, not the tank Every propane appliance has a nameplate that lists its input in BTU per hour. Emerson's LP-Gas Serviceman's Handbook says the best way to size a system is to add up the input of every appliance on it, including ones you plan to add later. The tank, regulators and pipe sizes all follow from that total. For rough planning, the handbook reprints approximate inputs from a table in NFPA 54, the National Fuel Gas Code. Your real numbers come from the nameplates of the equipment you choose. - Warm air furnace for a separate dwelling unit: about 60,000 BTU/hr (about 100,000 for a single-family home) - Storage water heater, 30 to 40 gallons: about 35,000; 50 gallons: about 50,000 - Freestanding range: about 65,000 - Clothes dryer: about 35,000 - Tankless water heater: roughly 142,800 at 2 gallons per minute and higher for larger units - Shop heaters vary widely, so read the nameplate ## One tank or two? Running a line from the house tank is often the simplest path when the tank has room for the added load and the new building is close by. A separate tank can make sense when the new building is far from the house, when the existing tank is already working hard in winter, or when you want the ADU's propane kept apart from the main house. We carry both leased and customer-owned tank options. Tank size also affects winter performance. A tank turns liquid into vapor more slowly in cold weather and when it is low, so a tank that barely keeps up with the house today may fall short once an ADU furnace is added. We can look at your tank and your appliance list and tell you which way makes sense. ## Setbacks can decide where the building goes A new ADU or shop can land too close to an existing tank. Placer County Building Services publishes these setbacks for above-ground ASME tanks below 5,000 feet of elevation. Check them before the site plan is final. Nevada and El Dorado counties run their own building departments, so if you build there, ask yours for its handout. Above 5,000 feet, the local fire district sets the requirements. Underground tanks are inspected and approved by the local fire district before building final. - Tanks up to 125 gallons: at least 5 feet from buildings and property lines - 126 to 500 gallons: at least 10 feet - 501 to 2,000 gallons: at least 25 feet (a single tank up to 1,200 gallons may be 10 feet away if no other tank is within 25 feet) - Any tank filled on site: the fill connection and liquid level gauge at least 10 feet from ignition sources such as an electrical service, A/C compressor or furnace, and from direct-vent appliance intakes and mechanical ventilation intakes ## Running the gas line Most detached ADUs and shops are fed by a buried line. The same county handout lists what inspectors expect to see, and American River Gas runs underground gas lines as one of our services. - Underground pipe must be polyethylene rated for gas or factory-coated steel, and new or used only for gas. - At least 12 inches of cover, or 18 inches where the pipe could be damaged, such as under a driveway. - Plastic pipe needs a tracer wire or tape along its full length so it can be located later. - The line is pressure tested to the county's standard, and every new appliance gets a leak test and its own shut-off valve within 6 feet. ## Where propane appliances can and cannot go Propane is heavier than air, so a leak settles in low spots. The California Mechanical Code, section 303.7.1, bars propane appliances from pits, basements and similar locations where the gas could collect, and allows them in an above-grade underfloor space or basement only with an approved way to remove unburned gas. Placer County's handout shows a screened propane drain at the lowest point of the underfloor area for a furnace installed there. At elevations between 2,500 and 5,000 feet, the county asks the building designer to specify how that requirement will be met, including keeping the drain clear of snow. That affects ADUs in the higher foothill towns, so raise it with your designer early. ## Shops and garages have their own hazards The Propane Education & Research Council warns that vapors from gasoline, paint thinner and solvents can be ignited by propane appliances, and that those vapors can travel along the floor and collect in low areas. A shop full of fuel cans and finishing products needs its heater placed and vented with that in mind. - Choose a heater designed and approved for indoor use, installed and vented to the outdoors. Never bring an outdoor heater inside to warm a shop. - Keep gasoline, solvents, rags and anything else that can burn away from burners. - Do not store spare propane cylinders in the shop or garage, even empty ones. Keep them outdoors, upright, valves closed. - Never run an engine or snow blower in a closed garage or shop. - Put a carbon monoxide alarm in any ADU with a fuel-burning appliance. Our carbon monoxide guide covers what California requires. ## Planning it with us Bring us in when you have a site plan and an appliance list, ideally before trenching or pouring. Call the office at (530) 888-7438, Monday through Friday from 8 to 4:30, closed noon to 1. We will look at your current tank, the new load and the distances, and tell you whether a line from the existing tank or a second tank fits better. If you smell gas at any time, leave the building first, then call 911 and us from outside. Questions ## Straight answers ### Can an ADU share the main house's propane tank? Often, if the tank can handle the combined load of every appliance on the property in cold weather and the line can be routed and sized for it. Otherwise a separate tank is the answer. ### How far does a propane tank have to be from a new ADU or shop? Placer County's handout lists 5 feet for tanks up to 125 gallons, 10 feet for 126 to 500 gallons and 25 feet for 501 to 2,000 gallons, below 5,000 feet of elevation. ### Can I put a propane heater in my garage or shop? Yes, if it is designed and approved for indoor use and installed and vented to code. Keep flammable liquids away from it, and never use an outdoor heater indoors. ### How deep does a propane line to a shop need to be buried? Placer County's handout calls for at least 12 inches of cover, and 18 inches where the pipe could be damaged, with a tracer wire on plastic pipe. [All questions →](https://americanrivergas.com/faq/)  ·  [Propane guides →](https://americanrivergas.com/guides/) Related ## Keep reading - [Underground Gas Lines](https://americanrivergas.com/services/underground-gas-lines/): Piping from the tank to the house and appliances. - [Propane Tank Installation](https://americanrivergas.com/services/propane-tank-installation/): Above-ground tanks set, connected and leak-tested. - [Propane Tank Sizes: Lease or Own](https://americanrivergas.com/services/tank-sizes-lease-or-own/): Which size fits your home, and leased vs owned tanks. - [Planning propane for new construction: tank placement and setbacks](https://americanrivergas.com/guides/propane-for-new-construction/): Buying, building & moving - [Carbon monoxide and propane appliances](https://americanrivergas.com/guides/carbon-monoxide-and-propane-appliances/): Safety & seasons Sources: [Placer County Building Services: LP gas tank installation below 5,000 ft elevation (handout)](https://www.placer.ca.gov/DocumentCenter/View/3291/Liquid-Propane-Gas-Tank-Installation-Below-5000-Foot-Elevation-PDF) · [Placer County Building Services: propane appliances (handout)](https://www.placer.ca.gov/DocumentCenter/View/3284/Propane-Appliances-PDF) · [Emerson Fisher LP-Gas Serviceman's Handbook (LP-10): determining total load](https://www.emerson.com/is/content/emerson/en/final-control/pressure-management/handbooks/lp-10-handbook-en-us-8439918.pdf) · [Propane Education & Research Council: Safety Guide for Propane Users (PRC-101063D, 2025)](https://cloudinary.propane.com/images/v1777645361/website-media/PRC-101063D-Propane-Safety-Booklet_digital-1_144644b80f7_151323cd231/PRC-101063D-Propane-Safety-Booklet_digital-1_144644b80f7_151323cd231.pdf)