Blue Shield® AS – Reliable, Cost-Effective Vapor Control for Wood Flooring

Looking for a dependable and affordable vapor control solution for your wood flooring installations? Blue Shield® AS (Saturated Asphalt Kraft) is a Grade D, Class III semi-permeable vapor retarder designed to protect flooring from moisture damage while offering added stability and noise suppression. Made with durable kraft paper and asphalt saturation, this underlayment delivers reliable performance for both residential and light commercial projects.

Easy to install and trusted in the industry, Blue Shield AS helps extend the life of your flooring by reducing vapor transmission and maintaining subfloor conditions.

Why Choose Blue Shield® AS?

• Effective vapor control—semi-permeable barrier helps prevent moisture damage

• Moisture-resistant—passes ASTM D-779 water resistance test

• Noise suppressing—adds stability and sound control under wood and tile floors

• Durable construction—made from 73.5 lb/rm kraft paper saturated with 26.5 lb asphalt

• Permeability rated at 17.4 perms (WVTR: 119.1 g/day/m²)—ideal for a balanced moisture barrier

Application Tips:

• Use as an underlayment for wood flooring over dry, level, and debris-free subfloors

• Not recommended for use directly over basements or crawl spaces without additional moisture mitigation

• Follow NWFA installation guidelines and local building codes for best results

Perfect For:

• Residential wood flooring installations

• Small commercial projects requiring moisture protection

• Tile flooring underlayment and industrial wrap applications

Pro Tip:

Store product between 60–70°F with 40–50% relative humidity to preserve performance. Use within 1 year for guaranteed results.

For cost-effective protection and long-term floor durability, trust Blue Shield® AS—proven moisture control you can count on.