Tyvek FlexWrap is applied wherever the parapet cap takes a turn, to ensure a watertight seal where the straight flashing will need to be cut.
The sheet membrane applied over the parapet caps doesn't stretch and must be carefully folded around corners.
3M High Strength 90 spray adhesive is used between layers to ensure a lasting bond. Here it is used to hold down a flap in the housewrap.
Using an adhesive especially helps on projects where it might be a while before the housewrap and flashing are covered up.
Flashing needs to wrap over the entire cap in one piece and hang down at least 4 to 6 inches over the housewrap to provide a good shingle effect.