Cover board with honeycomb layer
A cover board and roofing system including a cover board are disclosed. In one embodiment, the cover board includes a honeycomb layer positioned between a first face sheet and a second face sheet. The honeycomb layer comprises a honeycomb structure having a plurality of partition walls forming a plurality of cells. When the cover board is applied as part of a roof structure, including an insulation layer and a roof deck below the cover board, the roof structure exceeds requirements for Very Severe Hail Resistance according to the FM Approvals FM 4470 VSH impact resistance testing standard for Single-Ply, Polymer-Modified Bitumen Sheet, Built-Up Roof (BUR) and Liquid Applied Roof Assemblies.
1 . A cover board, comprising:
a first face sheet;
a honeycomb layer positioned adjacent to the first face sheet, the honeycomb layer comprising a honeycomb structure formed of thermoplastic polyolefin,
the honeycomb structure having a plurality of partition walls forming a plurality of cells;
a second face sheet positioned such that the honeycomb layer is between the first face sheet and the second face sheet; and
wherein each cell has a triangular cross-section and the honeycomb structure has a cell density of 4 to 10 cells per 10 mm 2 ;
wherein, when the cover board is applied as part of a roof structure including an insulation layer and a deck below the cover board, the roof structure exceeds requirements for Very Severe Hail Resistance according to FM Approvals FM 4470 VSH impact resistance testing standard for Single-Ply, Polymer-Modified Bitumen Sheet, Built-Up Roof (BUR), and Liquid Applied Roof Assemblies.
2 . The cover board of claim 1 , wherein the honeycomb layer comprises a thickness of 2 mm to 30 mm, and wherein the first face sheet and the second face sheet each comprise a glass, polymer or paper sheet having a thickness of approximately 20 mils to 100 mils.
3 . The cover board of claim 1 , wherein the first face sheet and the second face sheet each comprise a paper, glass, a thermoplastic polyolefin, a polycarbonate, a polypropylene, a polyaramid, or a polyethylene.
4 . The cover board of claim 1 , wherein the honeycomb structure comprises a density of 1 cell to 10 cells per 10 mm 2 .
5 . The cover board of claim 1 , wherein each of the plurality of cells further comprises a chamber defined by the walls of each cell.
6 . The cover board of claim 5 , wherein the chamber of each cell is at least partially filled with a foam, solid, flexible, or resilient material, or combination thereof.
7 . The cover board of claim 1 , wherein at least one of the first face sheet and second face sheet comprise a polymer membrane material configured to provide water shedding and resistance to water-ponding.
8 . The cover board of claim 1 , wherein the honeycomb layer is a flexible sheet material.
9 . A method, comprising:
attaching an insulation layer comprising polyisocyanurate to a deck of a roof structure;
obtaining a cover board, the cover board comprising:
a first face sheet;
a honeycomb layer positioned adjacent to the first face sheet, the honeycomb layer comprising a honeycomb structure formed of thermoplastic polyolefin,
the honeycomb structure having a plurality of partition walls forming a plurality of cells;
a second face sheet positioned such that the honeycomb layer is between the first face sheet and the second face sheet; and
wherein each cell has a triangular cross-section and the honeycomb structure has a cell density of 4 to 10 cells per 10 mm 2 ;
positioning the cover board over the insulation layer,
attaching a water shedding layer to an upper surface of the cover board,
wherein the roof structure exceeds requirements for Very Severe Hail Resistance according to FM Approvals FM 4470 VSH impact resistance testing standard for Single-Ply, Polymer-Modified Bitumen Sheet, Built-Up Roof (BUR), and Liquid Applied Roof Assemblies.
10 . The method of claim 9 , further comprising attaching a membrane layer over the insulation layer prior to positioning the cover board over the insulation layer.
11 . The method of claim 9 , further comprising attaching the cover board to the insulation layer by adhesive, laminating, welding, fasteners, or combinations thereof.
12 . A roofing system, comprising:
a deck,
an insulation material positioned over the deck; and
a cover board positioned over the insulation material, the cover board configured to provide severe hail resistance and comprising:
a first face sheet;
a honeycomb layer positioned adjacent to the first face sheet, the honeycomb layer comprising a honeycomb structure formed of thermoplastic polyolefin, the honeycomb structure having a plurality of partition walls forming a plurality of cells;
a second face sheet positioned such that the honeycomb layer is between the first face sheet and the second face sheet;
wherein each cell has a triangular cross-section and the honeycomb structure has a cell pitch-density of 4 to 10 cells per 10 mm 2 ;
wherein, when the cover board is applied as part of a roof structure including an insulation layer and a deck below the cover board, the roof structure exceeds requirements for Very Severe Hail Resistance according to FM Approvals FM 4470 VSH impact resistance testing standard for Single-Ply, Polymer-Modified Bitumen Sheet, Built-Up Roof (BUR), and Liquid Applied Roof Assemblies.
13 . The roofing system of claim 12 , further comprising an underlayment positioned over the insulation material and below the cover board, the underlayment comprising a polymer membrane configured to provide resistance to migration of water therethrough.
14 . The roofing system of claim 12 , wherein the cover board is attached over the insulation material by an adhesive, lamination, welding, a mechanical connection, or a combination thereof.
15 . The roofing system of claim 12 , wherein the insulation material comprises a layer of polyisocyanurate foam.
16 . The roofing system of claim 12 , wherein the first face sheet and second face sheet each comprise a face sheet formed from paper, glass, plastic, polymer, or combination thereof.
17 . The roofing system of claim 12 , wherein each of the cells of the plurality of cells comprises a chamber, and further comprising a foam, solid, flexible, resilient material, or a combination thereof received within the chambers of at least a portion of the cells of the plurality of cells.