Fire retardant roofing system, shingle and layer
Roofing shingle layers, roofing shingles, and roofing systems having fire retardant properties are provided. In certain exemplary embodiments, the roofing shingle layers, roofing shingles, or roofing systems include an expandable fire retardant material. The expandable fire retardant material may comprise expandable graphite, ammonium polyphosphate, or a combination thereof.
1. A layer of a roofing shingle having an upper surface and an under surface, the layer comprising:
a fibrous substrate;
an asphalt coating on the fibrous substrate;
granules disposed on the asphalt coating; and
expandable fire retardant material disposed directly on the upper surface of said layer as a particulate material,
wherein said expandable fire retardant material has an average bulk density ranging from 1 to 3 g/cm 3 and a start expansion temperature ranging from 150 to 250° C.;
wherein the expandable fire retardant material is a plurality of particles having an average particle size ranging from 50 to 1000 microns;
wherein said expandable fire retardant material is present in said layer in an amount ranging from 0.01 to 1.0 lb/square; and further
wherein the expandable fire retardant material is disposed only in an area within two inches of a sealant section.
2. A roofing shingle comprising at least two layers according to claim 1 .
3. The layer of roofing shingle of claim 1 , wherein the expandable fire retardant material comprises expandable graphite.
4. The layer of roofing shingle of claim 1 , wherein the expandable fire retardant material consists of expandable graphite.
5. A roofing system comprising a plurality of partially overlapping courses of roofing shingles thereby creating an overlapping seam, wherein each shingle comprises at least one layer comprising:
a fibrous substrate;
an asphalt coating on the fibrous substrate;
granules disposed on the asphalt coating; and
expandable fire retardant material disposed directly on the upper surface of said layer as a particulate material,
wherein said expandable fire retardant material expands upon exposure to fire at a temperature of at least 150° C. thereby closing at least a portion of the overlapping seam;
wherein the expandable fire retardant material is a plurality of particles having an average particle size ranging from 50 to 1000 microns; and
wherein the expandable fire retardant material is disposed only in an area within two inches of a sealant section.
6. The roofing system of claim 5 , wherein the roofing shingles are laminated roofing shingles.
7. A laminated roofing shingle having an upper surface and an under surface, the laminated roofing shingle comprising:
at least two layers bonded by an adhesive section, wherein each layer comprises:
a fibrous substrate;
an asphalt coating on the fibrous substrate;
granules disposed on the asphalt coating; and
expandable graphite particles having an average bulk density ranging from 1.3 to 2.8 g/cm 3 and a start expansion temperature ranging from 150 to 250° C., disposed directly on the upper surface,
wherein the expandable fire retardant material is a plurality of particles having an average particle size ranging from 50 to 1000 microns; and
wherein the expandable graphite particles are disposed only in an area within two inches of a sealant section.
8. The laminated roofing shingle of claim 7 , wherein the laminated roofing shingle comprises a plurality of sealant sections.