Abstract: A material (1) for installation over a plurality of regularly spaced joists (12) to insulate a floor structure (10), the material (1) having a plurality of spaced apart sets of linearly arranged holes (3) extending across the width of the material (1), the holes (3) intended to overly the joists so that once the material (1) is in place, flooring material (90) can be adhered to the joists (12) through the holes (3), each set of linearly arranged holes (3) allowing access to 50 to 98 percent of the length of the joist (12) overlain by the set of holes (3).

Abstract: An insulation material comprising a substrate (5) having a plurality of spaced attachment portions (7), each attachment portion (7) being formed so that in use structural members on either side of said substrate (5) can be adhered to one another where they overlie the attachment portions, and a plurality of spaced insulation portions (6) attached to said substrate (5) between said attachment portions (7).