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Validated Products
  • Listee
    • Westlake Royal Roofing
  • Manufacturer Location
    • Brentwood, NH
  • Category
    • Roofing Material
  • SubCategory
    • Underlayment
  • Certification(s)
    • ASTM D1970

Westlake Royal Citadel Plus

Westlake Royal Citadel Plus is a polymer modified bituminous sheet material intended for use as underlayment. Underlayment is manufactured as a fiberglass mat surface impregnated and coated with modified bitumen, with a self-adhesive underside and a polymeric surface. Underlayment rolls have approximate dimensions of 72ft x 3ft. Underlayment is self-adhered.


ASTM D1970
Product has met specification requirements of ASTM D1970.