How High To Stub Out Bathroom Sink Drain

How High To Stub Out Bathroom Sink Drain?

When plumbing a bathroom sink, it's essential to stub out the drain at the correct height to ensure proper drainage and avoid clogs. The stub-out height refers to the distance from the floor to the center of the drainpipe where the P-trap will connect. The most common height for bathroom sink drains is 18 inches (457 mm) from the finished floor to the center of the drainpipe. However, the stub-out height may vary depending on the sink model and the type of P-trap used.

Determining the Stub-Out Height

The stub-out height is typically determined by the sink manufacturer. It is recommended to refer to the sink's installation instructions to determine the specified stub-out height. If the manufacturer's specifications are not available, the following guidelines can be used:

For standard bathroom sinks, the stub-out height is typically 18 inches (457 mm) from the finished floor to the center of the drainpipe.
For vanity sinks, the stub-out height may vary depending on the sink model and the type of P-trap used. It is best to refer to the manufacturer's specifications or use the following measurement as a starting point: measure the distance from the bottom of the sink to the top of the P-trap, then subtract 1 inch (25 mm).

Adjusting the Stub-Out Height

If the existing stub-out height does not match the specified height, it may need to be adjusted. This can be done by either raising or lowering the stub-out pipe. To raise the stub-out, an extension piece can be added to the drainpipe. To lower the stub-out, the pipe can be cut and a new piece of pipe can be installed at the desired height.

Ensuring Proper Drainage

The correct stub-out height is crucial for ensuring proper drainage of the sink. If the stub-out is too low, the water may not drain properly and can cause clogs. If the stub-out is too high, the P-trap may not be able to create a proper seal, which can lead to leaks.

P-Trap Considerations

The type of P-trap used can also affect the stub-out height. A P-trap is a U-shaped pipe that connects the drainpipe to the sink drain. The P-trap creates a water seal that prevents sewer gases from entering the bathroom. The depth of the P-trap should be considered when determining the stub-out height.

Stubbing out the bathroom sink drain at the correct height is an essential aspect of plumbing a sink. By following the manufacturer's specifications or using the guidelines provided in this article, you can ensure proper drainage and avoid costly plumbing problems in the future.