Development Services

Plumbing Details, Diagrams & Tables

The following page provides details in relation to plumbing for various types of projects.

  • Galvanized steel water piping shall not be installed in the ground under a building, unless it is protected against corrosion by a machine applied coating or wrapping.
  • PVC water lines are not approved under or within buildings.
  • Copper tubing type L or heavier may be used in all locations. All joints installed below the floor slab shall be brazed.
  • Copper tubing type M or heavier may be used in the ground outside and within the building walls and attic.

The size of each section of the water piping system is determined by a combination of:

  • The minimum pressure available in the main.
  • The elevation of the highest outlet.
  • The distance to the most remote outlet.
  • The number of outlets supplied.
  • Exterior and interior hose water faucets and laundry sink type water faucets shall be protected by an approved non-removable type back-flow prevention device.
  • Gas piping may not be installed underneath the raised floor of a building when the gas line is in the ground or under/within a concrete floor slab of a building. The gas pipe can be attached to the raised wood floor joists minimum 6” above grade.
  • Gas piping shall not be installed in the ground unless it is protected against corrosion by a machine applied coating or wrapping.
  • Unions for gas pipe are only permitted at an exposed fixture appliance or equipment connection and in exposed exterior locations immediately on the discharge side of a building shut off valve.
  • The distance from the meter to the most remote outlet plus the gas demand of the appliance served determines the size of each section of gas piping system.

Once all gas pipes has been installed, perform an air pressure test on the new gas system. The air test shall be made by attaching an air compressor testing apparatus to any suitable opening, and, after closing all other inlets and outlets to the system, forcing air into the system until there is a uniform gauge pressure of 10 pounds per square inch. The pressure shall be held without induction of additional air for a period of at least 15 minutes.

Need to relocate or increase the capacity of your gas meter? Visit the Long Beach Energy Resources Department website for information.

Water heaters which depend on the combustion of fuel for heat shall not be installed in any room used or designed to be used for sleeping purposes, bathroom, clothes closets, or in any closet or other confined space opening into any bath or bedroom. Shed clearance to side property line is two feet, six inches and three feet to rear property line. Verify approved location of the water heater with the Zoning counter staff.

The termination of type-B vents shall be a minimum of four feet from the property line.

Testing & Inspection  

  • All work must be inspected and approved before being covered, concealed, or put into use. All tests must be witnessed by the inspector.
  • Building sewers shall be tested by plugging the end of the building sewer at its point of connection with the public sewer and completely filling the building sewer with water from the lowest to the highest point.
  • Drainage, and vent systems must be tested by filling with water and must be watertight. No section shall be tested with less than a 10-foot head of water.
  • Water piping must withstand the street main pressure or 50 psi pounds per square inch (psi) of air pressure without leaking.
  • Metallic gas piping must withstand 10 psi air pressure for at least 15 minutes without leaking.

Typical Installation of Water Heater in Metal Shed  

Installation Checklist:

  • Shed clearance to side property line is two feet, six inches and three feet to rear property line. Verify approved location with staff at the Planning counter.
  • Termination of type-B vent shall be minimum 4 feet from the property line. Gravity vents shall extend in a generally vertical direction with offsets not exceeding 45 degrees.
  • Double wall type-B vent requires minimum one-inch clearance to combustible materials. Double wall vent is required outside of the enclosure.
  • Single wall vent connector must be secured to down draft diverter and type-B vent with sheet metal screws.
  • A cold water shut off valve shall be installed for the service or replacement of the water heater.
  • Approved flexible water connectors are approved for water supply to heater within the enclosure only.
  • A combustion air opening in an exterior wall of one-square-inch per 4000 Btu rating of water heater is required within the upper and lower 12 inches of the enclosure.
  • A pressure/temperature relief valve is required to be installed on the water heater. Terminate the discharge line of the relief valve no more than two feet, nor less than six inches above the ground. The end of the discharge line may not be threaded.
  • The water heater shall be anchored or strapped with approved materials to resist horizontal displacement due to earthquake motion. Strapping shall be at points within the upper one-third and lower one-third of its vertical dimension. At the lower point, a minimum distance of four inches shall be maintained above the controls with the strapping.
  • An approved gas shut-off valve is required to be installed at the gas piping outlet, immediately ahead of the flex connector, and must be accessible.
  • A gas flex connector is limited to three feet in length.
  • An air pressure test is required for installation of new a gas line if the new line exceeds six feet. The test consists of pumping air into the new line to a pressure of 10 pounds per square inch for a period of 15 minutes without loss of pressure. The test must be witnessed by an inspector.

Installation Checklist:

  • Establish location of water heater in garage. The location may not block existing required off-street parking areas. Establish the best location for the installation of water heater vent.
  • Termination of AB vent shall be minimum four feet from the property line.
  • Water heaters generating a glow, spark or flame capable of igniting flammable vapors may be installed in a garage, provided the pilots, burners or heating elements and switches are at least 18 inches above the floor level. Provide an adequate platform to elevate the water heater.
  • Double wall type AB vent requires minimum one-inch clearance to combustible materials.
  • Type AB vent must be secured to the down draft diverter with sheet metal screws.
  • A cold water shut-off valve shall be installed for the service or replacement of the water heater.
  • Approved flexible water connectors are approved for water supply to the heater within the garage only.
  • Provide combustion air for water heater. If the volume of the garage equals at least 50 cubic feet per 1000 British thermal unit (Btu) per hour/h input of the water heater, no additional openings are needed. If not, combustion air openings in the exterior wall of the garage of one-square-inch per 4000 Btu rating of water heater is required within the upper and lower 12 inches of the garage.
  • A pressure/temperature relief valve is required to be installed on the water heater. Terminate the discharge line of the valve no more than two feet, nor less than six inches above the ground outside of the building.
  • The water heater shall be anchored or strapped with approved materials to resist horizontal displacement due to earthquake motion.
  • Provide air pressure test on the new gas system.

For water heaters over 40 gallons but less than 100 gallons, use ¾-inch electrical metallic tubing (EMT) conduit and 1½” metal strap. Water heaters over 100 gallons and/or water heaters more than 12 inches from a wall require a designed system.

Note: Approved manufactured water heater support kits sold at building and plumbing supply stores may be used as an alternate to these requirements.

Installation Checklist:

  • Locate wall studs on both sides of the water heater. Pre-drill holes for anchor bolts in stud center.
  • Measure distance around water heater. Cut two 1 ½” x 16” gauge straps to encompass water heater.
  • Drill holes in the ends of the straps and bend them 45 degrees.
  • Cut four pieces of 1½” EMT conduit to the proper length as shown in diagram and flatten ends.
  • Drill holes in flattened ends of conduit. Bend flattened ends 45 degrees on one side.
  • Install strapping. Strapping shall be located at points within the upper and lower one-third of the vertical dimension of the water heater.
  • At the lower point, a minimum distance of four inches shall be maintained above the controls. Wrap the straps around the heater and insert a 5/16” x 1¼” bolt with washer into the bent ends.
  • Install EMT conduit. Insert ¼” x 3” lag bolts through hole in ends of conduit into the wall stud and tighten. Insert 5/16" x 1¼” bolt, which is in strapping, through other end of conduit and tighten.

Typical On-Lot Sewer Detail  

Building sewers:

  • Shall be located only on the lot which they serve.
  • Shall be three inches minimum in diameter and 12" below ground if non-metallic.
  • Shall not be non-metallic when within two feet of any building except approved plastics.
  • Shall not be joined by means of cement mortar joints.
  • Shall be supported on a firm bed throughout their entire length.
  • Shall have a ¼" per foot slope toward the street sewer.
  • Shall be provided with a clean-out at their upper terminal, of changes in direction in excess of 135° and at intervals to not exceed 100 feet in straight runs.
  • Shall not be located in the same ditch with domestic water piping unless the water piping rests on a solid shelf 12" to one side and 12" above the sewer if clay sewer is used.
  • Shall not be located in an excavation which is deeper than the bottom of a parallel foundation unless the bottom edge of the excavation in at least one foot away from the foundation for each foot of excess depth.
  • Vertical drainage lines connecting with horizontal drainage lines shall enter through 45-degree wye branches, combination wye and 1/8 bend branches, or other approved fittings of equivalent sweep.
  • Horizontal drainage lines connecting with other horizontal drainage lines shall enter through 45-degree wye branches, combination wye and 1/8 bend branches, or other approved fittings of equivalent sweep.
  • Horizontal drainage lines, connecting with a vertical stack, shall enter through 45-degree wye branches, 60-degree wye branches, combination wye and 1/8 bend branches, sanitary tee branches, or other approved fittings of equivalent sweep.
  • Horizontal trap arms, connecting with a vertical stack or waste, shall enter through sanitary tee branches. A trap arm is that portion of a fixture drain between a trap and a vent. 
  • The size of vent piping shall be determined from its length and the total number of fixture units connected thereto. In addition, the drainage piping of each building and each connection to a public sewer shall be vented by means of one or more vent pipes, the aggregate cross-sectional area of which shall not be less than that of the largest building sewer.
  • Obtain a plumbing permit for installation of new gas pipe over 6 feet in length. A permit is not required for gas piping not more than 6 feet in length between an approved gas outlet and any gas-fired appliance, provided that any such gas-fired appliance is in the same room as the gas outlet.
  • If the gas meter needs to be relocated due to an addition or alteration to an existing building, call the Long Beach Gas Department Inspection Division. A Gas Department Inspector will establish the new location of the gas meter.
  • No gas piping shall be installed in or on the ground under any building or structure and all exposed gas piping shall be kept at least six inches above grade or structure.
  • Ferrous gas piping installed underground in exterior locations shall be protected from corrosion by approved factory coatings. All gas pipe protective coatings shall be machine applied. Apply listed primer and spirally wrap listed tape to provide protection to those fittings and short sections where the factory coating has been damaged or stripped for threading. Use minimum 10-mil tape stretched around the fittings and unprotected areas to provide a minimum 40-mil thickness. All horizontal metallic piping shall have at least 12 inches of earth cover. Contact Long Beach Development Services to request an inspection before covering pipe.
  • The gas test shall be performed after all gas piping authorized by the permit has been installed, and before any such piping has been covered or concealed.
  • All gas appliance connectors shall be removed from the gas piping that is to be tested. Pressure necessary to test gas system will damage the gas appliances.
  • Remove gas shut-off valves from all gas pipe outlets after gas system has been shut off at meter.
  • Cap all other inlets and outlets to the system. Gas shut-off valves will not hold pressure for the gas test.
  • Required air pressure tests of 10 pounds or less for low pressure gas systems shall be performed utilizing dial gauges of 1/10 pound incrementation or less. A 15-pound test gauge is most commonly used, however a maximum 20-pound gauge would be acceptable as well.
  • Install air pressure test dial gauge on gas pipe. Apply pipe dope or Teflon tape on pipe threads to ensure a proper seal.
  • Perform air pressure test. The air test shall be made by attaching an air compressor testing apparatus to any suitable opening, and, after closing all other inlets and outlets to the system, forcing air into the system until there is a uniform gauge pressure of 10 pounds per square inch. The pressure shall be held without induction of additional air for a period of at least 15 minutes. Note: Never fill the gas system with water.
  • If the gas piping system does not hold the required 10 pounds of pressure for 15 minutes, check the gas piping system for leaks. Leaks in gas piping shall be located by applying soapy water to the exterior of the piping when the gas piping system is under pressure. If a leak is present, the soapy solution will bubble. It shall not be permissible to repair defects in gas piping or fittings, but upon having been located, the defective pipe or fitting shall be removed and replaced with sound material.
  • After the gas piping system has been tested and holds pressure to pass the required test, call for final piping inspection. The inspector will witness the gas pressure test, and if the installation is found to comply, will approve the installation of the gas piping system. The inspector will then notify the Long Beach Energy Resources Department of the approval, who will then provide the service.