I'm moving the plumbing in a shower stall (no tub) and wanted to know if what I'm planning is OK to do. I'd like the shower valve to be on one wall and the outlet on the opposite wall, about 5.5 feet away. The hot and cold supply come from the crawlspace under the bathroom up the wall. Id like to take the outlet from the shower valve and route it back down the wall, into the crawl space, under the shower and back up the opposite wall. My concern is changing the direction of the water flow from the usual short path of directly upward from the valve to the longer distance it will be going. Too much pressure loss, air getting trapped, water hammer issues. Thanks again for your help. Jim