Insulation system for residential construction

An apparatus for installing loose-fill or dense pack fiberglass or cellulose insulation that is blown dry into a wall cavity of a wall of a building structure, wherein the wall includes a back wall, a top beam disposed vertically above a bottom beam, a plurality of vertical studs extending between the top and bottom beams, and a plurality of wall cavities, a width of each wall cavity defined between a pair of adjacent ones of the plurality of vertical studs, the apparatus comprising:

• a drapeable sheet of fabric having a width so dimensioned as to extend vertically from the bottom beam of the wall to the top beam of the wall and having a length so dimensioned as to extend horizontally across at least one wall cavity, the at least one wall cavity defined in part by the top beam, the bottom beam, and the back wall, wherein the drapeable sheet of fabric having a first region that is substantially impermeable to air and a second region contiguous with the first region, the second region having a permeability to air substantially greater than the impermeability of the first region, wherein the air permeability of the second region is uninterrupted across the drapeable sheet of fabric, and
• a horizontal strip configured for extending continuously across an entire width of the at least one wall cavity and configured for covering the second region of the drapeable sheet of fabric.