Tankless water heaters are devices used to supply a property with an unlimited supply of hot water. These units aren’t like the typical tank style water heater, which hold many gallons (typically around 40-50) of water inside a lined steel tank, keeping the water heated until it’s needed. Tankless water heaters only heat the water when the faucet is turned …

A type of treated safety glass that, when broken, crumbles into tiny pieces instead of jagged shards, thereby lessening the possibility of injury. Car windows are also make of tempered glass.

TPR valve: Temperature and Pressure Release valve. A safety device, installed on water heaters and boilers, intended to open (release) when the temperature or pressure inside the tank gets too high.

transite pipe: a term used to describe any fireproof, hard material, especially pipes, boards, siding and roofing. It is most frequently found in older homes, as the use of asbestos was phased out in the 1980s.

truss: a framework of individual members (typically wooden) joined together, typically in a triangular arrangement, engineered to span an area and provide support for the home’s roof.

union: a three-piece fitting that is used to join together two pieces of pipe, allowing them to be disconnected again without cutting the pipe.

Most attic areas are vented, meaning that the attic is designed for exterior air to flow through its space, ideally helping to keep the attic temperature and moisture levels moderated. Ambient temperature air flows in through the lower level vent openings, usually in the soffit area, passes through the attic area, and is drawn or forced out the upper level …

UPC: Uniform Plumbing Code. A set of procedures developed to guide the installation and inspection of plumbing systems, designed to help protect public health and safety. The code is typically updated every three years.

vacuum breaker: an attachment typically installed on exterior hose faucet and sprinkler systems that prevents water from being siphoned back into the water pipes.

vapor barrier: see “vapor retarder.”