A composite shingle having unitary construction is presented that includes a body shell, a plurality of longitudinal ribs, and a plurality of rib stiffeners. Further, the present composite shingle may also include transverse ribs, a depressed nailing zone, nailing zone ribs, and / or at least one alignment aid. The present composite shingle may also include spacing nibs. At least a portion of the outside face of composite shingle is textured to resemble slate or wood shake
shingles. The butt end wall has a height that creates depth in composite shingle to more closely resemble true slate and shake
shingles. The first side wall and second side wall generally taper from a greater height at the butt end to a lesser height at the top end. The longitudinal ribs extend downward from the bottom surface of the body shell to a common plane. There is a plurality of rib stiffeners that also extend downward from the bottom surface of the body shell and each rib stiffener end is integral with a longitudinal rib. The depressed nailing zone may also include nailing zone ribs. These ribs strengthen the area surrounding the nailing zone. Composite shingle may further comprise alignment aids including spacing nibs, a scale and / or a laying line. Additionally, the spacing nibs may be used in concert with a scale located on the top surface of the top surface to help the installer create offset composite shingle patterns or help make sure all the composite
shingles have a uniform tab
exposure.A plurality of assembled composite shingles of the present invention is also claimed as part of this invention. Finally, a method of applying multiple courses of shingles on a roof comprising the steps of providing an underlying shingle,
coupling this shingle to the roof, laying an overlying shingle of the present invention on top of a least a portion of the underlying shingle and
coupling the overlapping shingle to the roof is presented.