Cat 5 | Air and Waterproof Barrier Coating
Cat 5 by PROSOCO is a single-component, silyl-terminated polymer (STP) air and waterproof barrier designed for high-performance protection on structural surfaces. Applied with a sprayer or roller, Cat 5 creates a seamless, elastomeric membrane that resists air and water infiltration. This next-generation coating is engineered for demanding conditions, including hurricane-level winds and wet weather, while complying with the most stringent VOC regulations.
Product Description
Cat 5 is ideal for exterior sheathing, CMU backup walls, and pre-cast concrete, forming a flexible yet durable protective layer. Because it bonds tenaciously to damp substrates and cures in wet conditions, this barrier is especially suited for challenging climates. Additionally, it is solvent-free, isocyanate-free, and phthalate-free, making it safer to apply and environmentally responsible. Its light brown, viscous consistency is easy to apply and eliminates the need for primers on most surfaces.
Key Benefits of Cat 5
- Spray- or roll-application offers flexibility during installation
- Bonds directly to damp substrates without primer
- Complies with all current VOC regulations (<30 g/L)
- Forms a seamless air and water barrier membrane
- Performs in a wide range of temperatures and weather conditions
- Passes NFPA 285 and ABAA certification standards
Common Applications
- Exterior gypsum board and OSB sheathing
- CMU block walls and precast concrete walls
- High-performance air barriers in commercial and residential builds
- New construction or retrofit projects requiring enhanced weather protection
Storage & Packaging
Cat 5 is sold in 5-gallon pails with a shelf life of 1 year when stored unopened in a cool, dry place. Each gallon covers approximately 50–100 sq ft depending on the substrate, with higher coverage rates on smoother materials.
Product Properties
| Property | Value |
|---|---|
| Shelf Life | 1 year in tightly sealed, unopened container |
| VOC Content | <30 g/L |
| Form | Viscous liquid, mild odor, light brown color |
| Total Solids | 99% |
| Coverage Rate | 50–100 sq ft per gallon (gypsum, OSB, plywood), 50–80 sq ft per gallon (CMU) |
| WT/GAL | 11.3 lbs |
| Available Sizes | 5-gallon pail |
For best results, apply Cat 5 in conjunction with FastFlash to seal penetrations, rough openings, and transitions. Learn more at PROSOCO.
