The word “plumbing” comes from the Latin word plumbum, which is the element lead, and was so named because lead was used extensively in the development of piping systems. The practice of installing pipes and using the piping materials became known as plumbing.
Everything in a building that uses water falls under one of two categories; Fixture or Appliance. As the consumption points above perform their function, most produce waste/sewage components that will require removal by the waste/sewage side of the system. The minimum is an air gap. See cross connection control & backflow prevention for an overview of backflow prevention methods and devices currently in use, both through the use of mechanical and physical principles. Fixtures are devices that use water without an additional source of power.
Pin-hole leaks can occur anytime copper piping is improperly grounded and/or bonded; nonmetal piping, such as Pex or PVC, does not suffer from this problem. The phenomenon is known technically as stray current corrosion or electrolytic pitting. Pin-holing due to poor grounding or poor bonding occurs typically in homes where the original plumbing has been modified; homeowners may find a new plastic water filtration device or plastic repair union has interrupted the water pipe’s electrical continuity to ground when they start seeing pinhole water leaks after a recent install. Damage occurs rapidly, usually being seen about six months after the ground interruption.
Closet bolts are usually made of brass because of its strength and corrosion-resistance. They alone hold the closet to the flange. A water closet floor flange receives the closet bolts. The flange attaches the closet firmly to the structure. The flange should be secured to the structure with corrosion-resistant screws. The flange firmly holds the closet to the structure without putting any load on the drainage pipe that is attached to the flange. A wall-hung water closet bowl should be supported to the wall structure with a concealed carrier so that no load is transferred to the drainage pipe or connection.
Every plumbing fixture must have an attached vent. The top of stacks must be vented too, via a stack vent, which is sometimes called a stink pipe. DWV systems maintain neutral air pressure in the drains, allowing flow of water and sewage down drains and through waste pipes by gravity. As such, it is critical that a downward slope be maintained throughout. In relatively rare situations, a downward slope out of a building to the sewer cannot be created, and a special collection pit and grinding lift ‘sewage ejector’ pump are needed. By contrast, potable water supply systems operate under pressure to distribute water up through buildings.
Air admittance valves (AAVs or Durgo valves) are negative pressure-activated, one-way mechanical vents, used in a plumbing system to eliminate the need for conventional pipe venting and roof penetrations. A discharge of wastewater causes the AAV to open, releasing the vacuum and allowing air to enter plumbing vent pipe for proper drainage. Since AAVs will only function under negative pressure situations they are not suitable for all venting applications, such as venting a sump, where positive pressures are created when the sump fills.
Professional home inspectors are trained to inspect residential plumbing supply and fixtures. The Barrie Home Inspector has the education and knowledge to ensure your home is free from plumbing deficiencies.