Certified Siding

VSI developed its Product Certification Program as a means for manufacturers to independently verify the quality of vinyl and polypropylene siding products.

Vinyl siding certified through VSI’s Program is verified by a third-party, accredited inspection agency to meet or exceed ASTM D3679, the long-standing, accepted industry standard for quality vinyl siding. Click here for an Official List of Certified Products .

Vinyl siding certified through VSI's Program may also include colors that have been certified to meet or exceed the color retention requirements of ASTM D6864 or D7251 through VSI's Program . In addition to meeting the performance characteristics for weatherability, windload, and impact resistance covered under ASTM D3679, these products will resist major color changes in a variety of climates, based on two-year outdoor weathering studies.