I need help with metal siding installation. Do you need sheathing under metal sidin You don't need sheathing under metal siding, but it's a good idea to have a moisture barrier between the metal and the wall. The most common way to do this is with house wrap, which is a type of breathable membrane that prevents water infiltration while still allowing the building envelope to "breath" (allow moisture and water vapor to escape).

It depends on the type of metal siding. If it is a corrugated metal, you will need sheathing because the nails will not hold if you do not put something under the metal. If it is a metal panel, you may not need sheathing. I would recommend consulting an expert to find out for sure. Good luck!