The present invention provides exterior building products, such as roofing and siding, shake, shingles, siding, sheathing, panels, planks, vertical siding, soffit panels, fencing, decking, fascia, corner posts, column corners and trim boards in which a plurality of cementitious layers are provided with an improved interlaminar bond by employing a resinous bond promoter, a rheological agent, mechanical means to distribute fibers in a direction which is perpendicular to the machine direction so as to bridge between layers in the product, or a combination thereof. These techniques help to increase interlaminar bond strength to improve the mechanical properties of the product. When certain resinous bond promoters are used, the additional benefits of water absorption resistance and pigmentation throughout the product can be provided with minimal expense. Improvements in interlaminar bond strength of about 10 46% were observed with a percent elongation improvement of about 7%.