HOW TO repair and seal a leak on a Silicone-coated roof (671 Karna-Seal Silicone Sealant) Have a previously-coated Silicone roof that's got some problems and is potentially leaking into your building? The repair is easy with Karnak's 671 Karna-Seal Silicone Roof Sealant! Follow along as we walk you through the steps ...