Everbuild 145 butyl sealant is a traditional one component sealant based on polybutene that provides an effective weatherproof seal in a variety of exterior and interior applications it forms a skin in 24 hours but remains permanently plastic underneath the sealant accommodates joint movement of 5 is overpaintable and exhibits good uv and chemical resistance areas for use single glazing of metal concrete and wooden frames sealing metal roof panels pointing around soft and hardwood timber metal