July 3, 2014 at 12:54 pm #723
It’s not consistent, but here in the States (where ipe is wildly popular) we’re hearing more and more contractors telling us they’re sealing all four sides of the planks before installation. The thinking is that the planks won’t be oiled again, and it helps protects against the ingress of moisture that could contribute to cupping. (the cut ends, of course, get a coating of a wax-based emulsion to slow or stop the end-checking)
Most installers do sand before application.