Storm Proof Roof: How to Tape Roof Valleys, T-joints and Step Flashings With ZIP System Tape

September 16, 2018


Dry in a newly-sheathed roof with a roll of Zip System tape

Taping Roof valleys

When taping the valleys of ZIP System sheathing, there’s really two ways to do it: you can do it with one strip of our 6-inch tape, or you can do it with two overlapping layers of the 3 ¾. I’m going to demonstrate the two layers of 3 ¾ on this dormer valley right here.

Then install the second layer over the first, overlapping it a minimum of one inch. --- One-inch overlap.

In areas that require the use of an ice-and-water membrane in the valleys, ZIP System tape does not replace that need, so continue to add ice-and-water membranes where required by code.



When taping T-intersections, whether it’s on a roof or a wall, the minimum overlap is one inch. --- One inch minimum overlap.


Rigid metal flashing

Whenever transitioning to a rigid flashing from a vertical surface on ZIP wall, the easiest thing to do is install the rigid flashing and then tape over the vertical lay. That involves whether it’s base-flashing for brick, could be a weep screed on stucco.

Here we got some step flashing on a dormer. It would be the same for all of them.

Simply take your ZIP System tape, and that’s it.


—This video is provided by ZIP System®, one of ProTradeCraft’s advertisers. A next-generation exterior roof and wall solution, ZIP System streamlines the weatherization process with an integrated water-resistive barrier and taped seams replacing the need for house wrap or felt, while eliminating the risk of trapped water between sheathing and barrier and protecting against air leakage. View all Zip System's content