After you have completed your detail work by using FastFlash to protect all rough openings, penetrations, nail heads, and board seams, you're ready for your field coating.
Cat 5 is the air barrier field coating which completes the WRB system. Cat 5 is a permeable air barrier. It's meant to prevent water from entering but to also allow water vapor to exit. Moisture that is trapped inside your wall is a problem that you want to avoid so as long as your building can breathe it'll be a healthy building.
Featured in this video
Fully Saturate the Nap
We're going to show how it's applied with a roller but it can also be spray applied. You want to make sure that you fully saturate the nap in the beginning so that you get good full coverage on the nap and you can roll it out easily.
Roll On Until You Can't See Through It
With Cat 5 and all of PROSOCO’s air barrier products, they are designed with the intention that when you can no longer see through the product, that is when the product is applied at the correct thickness. So as long as you can't see the substrate beneath the Cat 5, you have the right thickness.
Cat 5 should be installed at about 12 to 15 mil thickness. Same as FastFlash. It also has the same moisture cure qualities as the FastFlash. The Cat 5 is colored adobe brown so you know what sequence level you are on the project.
Overlap FastFlash At Least One Inch
Cat 5 should overlap the FastFlash a minimum 1 inch over your Fast Flash.
Create Pinhole-Free Membrane
Cat 5 can be either roller applied or spray applied. When installing the Cat 5, the key objective is to create a pinhole free membrane. So whenever you're done applying it, you should visually inspect your surface that there are no pinholes.
Cat 5 is named Cat 5 because it can withstand winds up to 155 mph Category 5 hurricane. PROSOCO has tested Cat 5 to extreme winds and wind driven rains and in those tests, the wall actually failed before the product did.
Cat 5 also comes in a rain screen version which is a dark charcoal almost black color. That product is UV stable for your open jointed system rain screen applications .
With FastFlash installed around rough opening and for detail work and Cat 5 installed as the air barrier field coating across the field of the wall, you now have a seamless, and monolithic air barrier system on your building.
