Compact Board Underlay System EWA22. Heavy duty polystyrene underlay, suitable for use with all Laminate and Engineered wood floors. This is an ideal underlay for all types of subfloors as it has numerous attributes; its light weight ensures it is easy to handle and it will help level out, slightly uneven floors. The product is dust and fibre free ensuring it is good for the environment and anti-allergenic. Due to the construction of the board it has a high weight resistance, this also gives it a 2.2 TOG rating which is ideal for insulating cold rooms. Compact board has a very good sound absorption rate to help lower the effects of reflective sound. When used on concrete floors we suggest that the joints are taped with our vapour barrier tape.