Energy Efficient Shingles

Abstract

A novel energy efficient shingle is disclosed. The shingle is layered with the top layer comprising recycled glass cullet coated with a reflecting material such as TiO 2 . The novel shingle provides significant improvement in the Solar Reflectance Index (SRI).

1 . A roof covering comprising a substrate mat, an asphalt binder backdust, and white pigment coated glass cullet. 
     
     
         2 . A roof covering according to  claim 1  wherein the white pigment is selected from a group consisting of Sb 2 O 3 , BaSO 4 , PbCO 3 .Pb(OH) 2 , TiO 2 , and ZnO. 
     
     
         3 . A roof covering according to  claim 1  wherein the white pigment comprises TiO 2 . 
     
     
         4 . A roof covering according to  claim 1  wherein the mat is selected from a group consisting of organic felt and fiberglass; wherein said mat has a density of between 0.15 and 0.30 pounds per square foot. 
     
     
         5 . A roof covering according to  claim 1 , wherein the mat is fiberglass. 
     
     
         6 . A roof covering according to  claim 1  that is a plurality of shingles. 
     
     
         7 . A shingle according to  claim 6 , wherein the shingle comprises:
 a. A mat impregnated with an asphalt binder comprising air blown asphalt and glass cullet wherein the mat has a top side and a bottom side, and   b. wherein the top side of the mat is imbedded with TiO 2  coated glass cullet, and   c. wherein the bottom side of the mat is imbedded with backdust comprising glass cullet; and   d. wherein the shingle is oriented so that the top side of the shingle faces the atmosphere and the bottom side of the shingle is placed against the roof.   
     
     
         8 . An asphalt binder according to  claim 7  wherein the air blown asphalt is between 30% and 40% by weight of the glass cullet. 
     
     
         9 . An asphalt binder according to  claim 8  wherein the glass cullet is sized between 35 μm to 200 μm. 
     
     
         10 . A TiO 2  coated glass cullet according to  claim 7  wherein the TiO 2  is between 7% and 11% by weight of the glass cullet. 
     
     
         11 . A glass cullet according to  claim 10  wherein the glass cullet is sized between 500 μm and 3.0 mm. 
     
     
         12 . A glass cullet used for backdust according to  claim 7  wherein the glass cullet is sized between 70 μm and 600 μm. 
     
     
         13 . A shingle according to  claim 7  wherein the surface of the bottom layer of the mat is covered with glass cullet at coverage of about 0.3 g/sq.in. to about 1.3 g/sq.in. of recycled glass cullet. 
     
     
         14 . A shingle according to  claim 7  wherein the surface of the top surface of the mat is covered with coated glass cullet at coverage of about 1.5 g/sq.in. to about 2.5 g/sq.in.