What is the minimum and maximum height of a standpipe?
Standpipes shall extend not less than 18 inches (457 mm) but not greater than 42 inches (1066 mm) above the trap weir. Access shall be provided to standpipes and drains for rodding.
What is the minimum height of a standpipe?
Also, the 18-inch minimum height of the standpipe intends to prevent the possibility of the clothes washer’s pumped waste from overflowing the standpipe.
How tall should a washing machine drain stack be?
Laundry standpipes must be tall enough to extend past the washing machine’s overflow line—typically 30-36” in height, or 18”-30” above the trap.