Place a 4-inch 90 degree coupler at the base of each downspout and dry fit a length of 4-inch PVC pipe into the coupler and lay the pipe on the ground in the direction you intend to drain the storm water.
Continue to lay and dry fit pipes from the base of each downspout. To reduce the amount of pipe you need to lay, you can connect pipes using a 4-inch Y coupler. If you are connecting a total of 4 pipes into one drainage line, you should connect the two secondary 4-inch pipe lines to a 6-inch main drainage pipe with a 4-inch to 6-inch Y connector.
Cut any excess pipe length by marking the pipe with a pencil and carefully cutting the pipe with a hacksaw.
Dig a trench 12 to 14 inches deep to bury your pipe. The trench should be shallower at the downspout and progressively deeper away from the foundation. To ensure good drainage you should plan on a slope of 1/4-inch per foot of pipe.
Glue your pipes together and allow the cement to set.
Bury the drainage pipes.
Things You Will Need
- 4-inch PVC pipe
- 4-inch 90-degree PVC pipe coupling
- PVC Y-connector that connects two 4-inch pipes to one 4-inch pipe
- PVC Y-connector that connects two 4-inch pipes to one 6-inch pipe
- 6-inch PVC pipe
- measuring tape
- PVC cement
- trenching shovel
- Schedule 40 or SDR 35 PVC pipe is recommended for this project.