It will be ok even for outside.I mounted the vertical u-channels outside, underneath the eves of the house.First I mounted some hardwood (1" X 4") to the wall studs, with 1/4" X 4 1/2" Lags.Then mounted the u-channels on the 1 x 4's.Had some screws that were much longer than the ones provided with the kit. (I have no idea how the provided screws would apply with secure mounting) Way too short!Anyway, I'm ordering another so I can add more space for the garage.Overall, it's a ok kit. Nothing spectacular, but a good price.