Count on IKO for the best in permeable wall insulation systems. IKO’s innovative building envelope insulation systems are at the forefront of wall design. IKO Ener-Air™ high performing polyisocyanurate rigid foam insulation sheathing system is an effective all-in-one product when joined together on a building exterior using IKO’s AquaBarrier™ VP Tapes. The permeable rigid board insulation is suitable for either new construction or retrofit applications.