Fixtures In Walls
Wall mounted plumbing fixtures require mounting brackets to be installed within the wall (concealed). The dimensions vary based on the type of bracket, the accessories required, and the model of the carrier. The dimensions below are based on minimum requirements and come from the Plumbing and Drainage Institute. The PDI has a handy PDF chart of space requirements for plumbing fixture supports. Refer to manufacturer information for specific requirements. Ball valves are made with a rotating sphere that has a hole in it.
In the open position, the hole in the sphere is in line with the pipe. When closed, the hole in the sphere is perpendicular to the pipe. The lever handle operates the valve, but also serves as an indicator for whether the valve is open or closed. When the lever is parallel to the pipe, the valve is open. Gate valves control water flow by raising or lowering the gate, which is generally a piece of metal. There is a wheel or knob at the top of a gate valve that controls the height of the gate – this, in turn, affects the flow of water.
Unfortunately, the wheel doesn’t provide any indication of whether the valve is open or closed, or to what extent. Gate valves provide a reasonable seal, but they should not be used to adjust flow – they should be open or closed. Gate valves may not be very durable and are susceptible to corrosion, which will cause the valve to get stuck in the open or closed position. Butterfly valves have a disc that is equal in size to the inside diameter of the pipe. This disc is attached to a lever handle that rotates the disc, which adjusts the flow of water.
The main drawback to butterfly valves is that the control disc is always present within the flow of water (even when fully open) so there will always be a pressure drop when using them. A diaphragm valve is similar to a gate valve in that there is a wheel or knob that moves an element in the valve fitting, which limits the flow of water. In a diaphragm valve, the element is a diaphragm that settles down over a saddle, thus stopping water flow. The diagram below is a weir-type diaphragm valve, where water passes over a weir. There is also a straight-type diaphragm valve, which doesn’t force water over a weir.