Since 2007, a plumbing permit has been needed to install a hot-water heater in Texas, requiring a licensed plumber to tackle the project in accordance with state plumbing code. With the International Construction Codes forming the basis of Texas' statewide plumbing and heating codes, installation of hot-water heaters meets internationally agreed upon conventions.
Water heaters may not be installed in a bedroom or a closet or bathroom accessed through a bedroom, or in any room with air-handling equipment such as an air-conditioning unit. If installed in an attic, builders must provide access to the water heater large enough for it to be removed if it fails, with at least 30 inches of headspace and 22 inches of width in the access path, and have continuous solid flooring at least 24-inches wide. If installed in a garage, the water heater's pilot light and gas burners must be at least 18 inches from the floor.
When installed, water heaters must be equipped with a drain pan at least 1.5 inches deep, large enough to catch condensation and other drips from any spot on the bottom of the water heater. This drain pan must be equipped with a pipe at least 3/4-of-an inch in diameter, which drains into a floor drain. If no floor drain is available, it must terminate outside of the house at a height between 6 and 24 inches.
Gas water heaters must be equipped with a double-wall vent built within a minimum of one inch of combustibles. The vent must slant upward at all points, and must only have one offset of more than 60 degrees. All other offsets must be 45 degrees or less. The vent must be at least five feet long and terminate in an approved vent cap.
All water heaters must be installed to plumbing and electrical systems in a way that allows them to be shut down from the electrical supply in a method consistent with the ICC Electrical code.