Structural barrier system
An environmental barrier composition and method for forming a structural barrier system to seal structural openings such as doors and windows is provided. The composition includes a liquid rosin that is silyl-terminated polyether, a filler material, and a curing catalyst. The method includes applying the composition to a prepared through-hole in combination with flashing material at least along a bottom surface of the through-hole and installation of a window or door into the prepared through-hole to form a barrier system in which a continuous film can be easily inspected, is waterproof, meet air barrier requirements of ASTM E2178, has elastomeric properties, allows substrate expansion, contraction, and movement, does not shrink or lose volume as it cures, and cures rapidly with sufficient adhesion to transition flashing to incorporate into a designed drainage plane and allow integration of a continuous air barrier system where the barrier is at least semi-vapor-permeable.
1. A method of forming a structural barrier system for a through-hole in a wall, comprising:
applying and spreading a coating composition in a liquid state to at least one prepared surface surrounding the through-hole in the wall to form a film of the coating composition on the at least one prepared surface, the coating composition comprising a liquid resin in the form of a silyl-terminated polyether and a curing catalyst;
allowing the film of the coating composition to cure to form a waterproof flashing layer; and
installing a framed window or door unit in the through-hole after the coating composition has cured.
2. The method of claim 1 , further comprising after spreading the coating composition to a desired thickness, applying a sheet of flashing to a selected area of the surface surrounding the through-hole and at least partially on the coating composition.
3. The method of claim 1 , wherein the film is spread to a thickness of about 10 to 14 mils.
4. The method of claim 1 , wherein the film is spread to a thickness of about 12 mil.
5. The method as in claim 1 wherein the coating composition is applied to the least one prepared surface surrounding the through-hole in the wall using a caulking gun.
6. The method as in claim 1 wherein the coating composition is spread on the at least one prepared surface using a roller.
7. The method of claim 2 wherein the silyl-terminated polyether is polypropylene oxide capped at respective termini by a silyl group represented by:
—SiR 1 t (OR 2 ) 3-t , wherein, t is 0, 1 or 2, R 1 and R 2 are the same or different and independently an alkyl group.
8. The method of claim 7 wherein the silyl group is dimethoxymethylsilyl.
9. The method of claim 1 wherein the coating composition further comprises calcium carbonate as a filler.
10. The method of claim 2 wherein the curing catalyst is an organotin compound.