UnderDeck Pitch Rail by Zip-Up
Zip-Up UnderDeck Pitch Rails are the foundation for the entire Zip-Up system, as they form the pitch which directs water away from your home. The system works by creating a slope of 1/8 per foot. Simply put, a 1/2 Pitch Rail needs to be installed four feet from the house, then a 1 Pitch Rail eight feet from the house, and so on, adding 1/2 to the height of the Pitch Rail every four feet.
Pitch Rails should be installed using a deck screw longer than the height of the rail. In the case of slightly uneven joists, only attach the Pitch Rail at the longest (or lowest-hanging) joists, and take care not to over-torque the screws.
Using these dense PVC Pitch Rails will provide ultimate stability without risk of rot. Multiple Pitch Rails may be stacked to achieve the height needed, and taping them together can help make installation a smoother process. Some users of the Zip-Up UnderDeck system choose to cut their own Pitch Rails out of excess cedar or pressure-treated pine 2x4s, and the overall Zip-Up system works equally effectively.
Start here with our handy Zip-Up UnderDeck Calculator
First determine the number of pitch rails needed for your system. Measure the depth of the deck and divide the total (in feet) by 4, since a pitch rail is needed every 4 feet. (Example: 10 foot deck = 10/4 = 2.5)
Round down to a whole number. The first rail is 1/2 and is placed 4 feet from the house. Add 1/2 to the pitch rail height at each 4-foot increment. (Example: Pitch Rail 1= 1/2 at 4 feet, Pitch Rail 2= 1 at 8 feet)
*Pitch Rails are only offered in 12 foot sections. They can be cut to size.