In the past I have done this with either PVC pipe or the black tile pipe that has the sock around it. I would prefer PVC. I am draining two downspouts into one outlet and flowing the water about 40ft from the building to a catch basin where it will empty into there ditch area by the driveway. This is a commercial building were working with here. Do any of you guys do this differently or suggest another route to get the water out of the building area? This is a bank - 2 story but they added a drive thru and there are 2 down spouts draining in this area. Were going to landspace/seed/irrigate this but they want the water out of there besides draining onto the landscape.