When installing new fixtures in your bathroom, making sure the water supply lines and drains are properly placed does more than help you meet local code. It also makes it easier to remodel in the future, since vanities, sink basins and even toilets are designed to accommodate those standards. Does this Spark an idea?
Water Supply Lines
In a bathroom sink, the supply lines run out from the wall into the back side of the vanity. The usual height for the lines is 22 to 24 inches off the finished floor. It's unusual to bring them up any higher than 24 inches; they'll get too close to the sink basin and will be harder to access and work with. The supply lines are typically placed only 4 inches away from the sink drain.
Drains
The drain line for the bathroom sink should be centered inside the vanity cabinet. It can be placed between 18 and 24 inches off the floor. The height varies a little according to the vanity size; taller vanities need higher supply and drain lines, while lower ones shift the line placement down. If you're putting in a long vanity with double sinks, centering the drains gets more complicated, but the standard heights for supply and drain lines remain the same.
Standards
Water supply lines for toilets must have shut-off valves connected to them. While the shut-offs aren't required in most municipalities for sink supply lines, it's a good idea to have them. It makes working on your sink much easier, since you won't need to turn off the water supply for your home to avoid the risk of flooding. The sink drain must be connected to a trap to protect your home from the possibility of sewer gas drifting back up the drain pipe.
Considerations
While these are standard heights for plumbing, check your local codes before running any new water or drain lines in your bathroom. A building inspector or a licensed plumber can double check your plans to be sure they meet local as well as national regulations. Some areas are starting to require shut-offs on supply lines, so it's best to double check before getting too far into your project.
Tags: supply lines, drain lines, bathroom sink, check your, double check
