A pre-cut resilient fibrous insulation blanket includes a plurality of longitudinally extending blanket sections that are formed in the blanket by a plurality of laterally spaced apart cut and separable connector arrangements that hold the insulation blanket together for handling but enable the insulation blanket to be separated at any of the cut and separable connector arrangements to form a reduced width resilient fibrous insulation blanket. The number and widths of the blanket sections together with the lateral compressibility and resilience of the insulation blanket or a reduced width insulation blanket formed from the insulation blanket enable the insulation of essentially any width framework cavity up to the width of the insulation blanket with no more than one separation of the insulation blanket.