NP-EIFS non-permissive exterior insulation and finish systems concept technology and details
A new concept wall system is provided, wherein the Exterior Insulation and Finish System cladding is created using components with no water absorption, a very low vapor permeability and sealing properties, accommodated with an installation technology which extend the materials properties to the assembly, together with bonding and sealing the intersections and terminations, creating a Non-Permissive to water and vapor diffusion, Exterior Insulation and Finish System (NP-EIFS). The present invention relates to an EIFS cladding having two air and vapor barriers, one applied to the substrate, a continuous liquid membrane with sheathing joints sealed to be moisture barrier for inside vapors, and an exterior weather and vapor barrier which is created using closed cell extruded polystyrene insulation boards, special assembled with joints sealed, to create a non-permissive insulation envelope of the enclosure. Another object of the invention is to provide waterproof and air/vapor-proof details, a new concept of flashing and sealant application around windows/doors and other constructive elements to avoid thermal bridges and air leakage inside thermal envelope and wall assembly. Methods of installation are included.
1. A method of installing a non-permissive insulation system on an associated building substrate sheathing, the method comprising the steps of:
providing vapor impermeable extruded insulation boards having edges designed to form separate and symmetrical inner and outer sealing-joints when said insulation boards are assembled;
installing the insulation boards by sealing the inner sealing-joints with closed-cell expandable polyurethane foam, expanding bond-and-seal insulation materials;
sealing the outer sealing-joints with closed-cell expandable polyurethane foam after the inner closed-cell expandable polyurethane foam sealant is cured;
installing the expanding bond-and-seal insulation materials to stick, fill and seal the joints between the insulation boards and joints between the insulation boards and constructive elements;
applying impermeable sealant material to the sealing-joints, and any gaps filled with the expanding bond-and-seal insulation materials.
2. The method of claim 1 , further comprising applying a reinforcing layer comprising fiberglass mesh embedded in polymer-modified cement over an outer surface of the insulation boards.
3. The method of claim 2 , further comprising installing a finishing system over the reinforcing layer.