Yes, NewTechWood US05 fascia boards could be used as siding, installed with NewTechWood fascia screws and fascia tool for setting the screws and allowing for expansion and contraction to prevent warping. Please keep in mind that such an installation will not stop the continued degradation of any existing board and baton siding over which this is laid. It is also best practice to covering the wall surface with a house wrap before installing our fascia boards.