Basement bathroom plumbing is commonly referred to as sub-rough plumbing.
One of the first things that happens when a home is being built, is the basement bathroom plumbing is installed. This is done as soon as the footings and foundation are poured and the forms are stripped off.
Sometimes the gravel will be laid before the plumbing and then the plumber has to dig a trench in the gravel so the pipes will begin at the same level, and even with the top of the gravel. Those pipes will eventually be entirely below the gravel as the pipes are laid for gravitational pull in helping sewage to exit your home.
Having just finished our home I learned this fact right up front. The hole is dug, the footings and foundations are poured, and then the plumber comes and puts in the plumbing pipes that ultimately connect with the city sewer line, or your own septic tank.
The plumbing lines have to be sloping gradually downward, so that gravity will help the flow of water and sewage as it flows towards the final destination.
With the use of flexible plumbing pipes, many of the abrupt right angles can be avoided, which might cause a buildup and eventually a clog in the line. For basement plumbing pipes that are underground and undercement, usually cast iron or heavy plastic pipes are used.
The plumber will only take the sewer line out 18-24 inches beyond the footings of your home, where your excavator, or whoever you designate, will need to connect and lay the remainder of the sewer line, which connects to the septic or city lines.
Every sewer line has to have exhaust lines which also helps the flow as gravity pulls the sewage gradually to the point of destination.
Once basement bathroom plumbing lines have been installed, then the cement flatwork can be poured. If mistakes are made, then plumbers often have to jackhammer up the cement and make changes, but it's obviously easier, and cheaper, to do it right the first time.
People who own their own homes and then want to put in a basement bathroom have other options of pumping the sewage waters "up" to the exit line, or cutting into the existing line if the exit sewer line is below the cement floor.
Linda Baxter is
a piano teacher, and a stay at home mom of nine children, with a total of 22
grandchildren. She acted as General Contractor for building their
retirement home. She hired and paid subcontractors, was overseer of
all construction work (with the help of her husband, RL), and did
most of this from her “armchair”.and telephone. She freely
shares her experiences on her website, http://www.home-built4u.com,
hoping to help other potential owner/builders escape some of the
pitfalls she and RL experienced while being their own GC.
Disclaimer: All information on this site is
provided for informational purposes only! By no means is any
information presented herein intended to substitute for the advice
provided to you by any health care or other professional or
organization.