Fire resistant composite boards and methods

1. A roofing system comprising:

a roofing board, wherein the roofing board comprises a composite core material comprising:

between 40% and 70% of expanded perlite;

between 30% and 60% of paper products;

between 1.5% and 10% of a starch binder; and

between 1.0% and 5% asphalt; and

a mineral based material coating applied to one or more major surfaces of the roofing board, the mineral based material coating being applied in an amount between the range of about 0.05 lbs/ft 2 and about 0.70 lbs/ft 2 .

2. The roofing system of claim 1 , wherein:

the roofing board comprises one or more of the following materials:

wood fibers;

perlite;

polyisocyanurate;

polystyrene;

extruded polystyrene;

cellular glass; or

gypsum.

3. The roofing system of claim 1 , wherein:

the roofing board comprises a foam core sandwiched between two nonwoven facer material layers.

4. The roofing system of claim 1 , further comprising:

a roofing membrane configured to be positioned atop the roofing board and coupled therewith.

5. The roofing system of claim 4 , wherein the roofing membrane comprises one or more of:

polyvinyl chloride (PVC);

thermoplastic polyolefin (TPO);

ethylene propylene diene monomer rubber (EPDM); or

bitumen.

6. The roofing system of claim 1 , further comprising:

a roof deck, wherein the roofing board is configured to be positioned atop the roof deck and coupled therewith.

7. The roofing system of claim 1 , further comprising:

a glass fiber mat coupled with a major surface of the roofing board, the glass fiber mat being saturated with the mineral based material coating.

8. The roofing system of claim 1 , wherein the roofing board further comprises:

a glass mat facer coupled with one surface of the composite core, the glass mat facer having a mat weight per unit area of between about 0.9 and 3.0 lbs/100 ft 2 .

9. The roofing system of claim 1 , wherein:

the mineral based material coating comprises between about 25% and 50% water and between about 50% and 75% of a composition of solid materials;

the solid materials comprise between about 44% and 94% calcium carbonate, between about 5% and 10% sodium silicate, and between about 1% and 5% of latex; and

the coating limits air flow through the roofing board, thus enabling the roofing board to pass the UL 790 class A tests.

10. A roofing system comprising:

a roofing board; and

a mineral based material coating applied to one or more major surfaces of the roofing board, wherein:

the mineral based material coating comprises between about 25% and 50% water and between about 50% and 75% of a composition of solid materials;

the solid materials comprise between about 44% and 94% calcium carbonate, between about 5% and 10% sodium silicate, and between about 1% and 5% of latex; and

the coating limits air flow through the roofing board, thus enabling the roofing board to pass the UL 790 class A tests.

11. A method of manufacturing a roofing board comprising:

providing a roofing board, applying a mineral based material to at least one major surface of the roofing board, the mineral based material being applied such that the roofing board comprises a coating weight per unit area of between about 0.05 lbs/ft 2 and about 0.70 lbs/ft 2 , wherein:

the mineral based material coating comprises between about 25% and 50% water and between about 50% and 75% of a composition of solid materials;

the solid materials comprise between about 44% and 94% calcium carbonate, between about 5% and 10% sodium silicate, and between about 1% and 5% of latex; and

the coating limits air flow through the roofing board, thus enabling the roofing board to pass the UL 790 class A tests.

12. The method of manufacturing a roofing board of claim 11 , further comprising:

securing a roofing membrane to the roofing board.

13. The method of manufacturing a roofing board of claim 11 , further comprising:

coupling a glass mat to at least one major surface of the roofing board using an adhesive such that the at least one major surface is faced with the glass mat.

14. The method of manufacturing a roofing board of claim 13 , further comprising:

applying the mineral based material to the faced glass mat surface of the roofing board.

15. The method of manufacturing a roofing board of claim 13 , further comprising:

applying a second glass mat to the other major surface of the roofing board such that both major surfaces of the roofing board are faced with a glass mat; and

applying a coating to the other faced glass mat surface of the roofing board, the coating being applied so as to comprise a coating weight per unit area of less than 0.10 lbs/ft 2 .

16. The method of manufacturing a roofing board of claim 14 , wherein:

the faced glass mat comprising the coating weight per unit area of at least 0.10 lbs 2 faces a roof deck.

17. The method of manufacturing a roofing board of claim 11 , wherein:

the mineral based material comprises between about 25% and 50% water and between about 50% and 75% of a composition of solid materials when applied;

the coating is approximately 100% solids after drying.

18. The method of manufacturing a roofing board of claim 17 , wherein:

the solid materials further comprise one or more of clay, perlite, fiber glass, silica, fly ash, ceramic spheres, cement, vermiculite, titanium dioxide, zinc oxide, or gypsum.

19. The method of manufacturing a roofing board of claim 11 , wherein the roofing board comprises:

a composite core material comprising:

between 40% and 70% of expanded perlite;

between 30% and 60% of paper products;

between 1.5% and 10% of a starch binder; and

between 1.0% and 5% asphalt.

20. The method of manufacturing a roofing board of claim 11 , wherein:

the roofing board comprises a foam core sandwiched between two nonwoven facer material layers.