Use high-performance acrylic-latex, acrylic, acrylic-silicone, polyurethane, polysulfide or terpolymer rubber caulks or sealants to seal gaps around windows, doors, corners, and other exterior joints that are exposed to potential water intrusion. Pure silicone and clear caulks do not work well on Western Red Cedar and are not recommended. Caulking is not a permanent solution and as such requires regular maintenance. If not inspected and maintained, caulking may fail and trap water, creating severe moisture problems. Do not rely on it as the only barrier to moisture penetration. Do not caulk areas that will prevent moisture from escaping the wall cavity (e.g., under windows and around flashing).