Some security cameras are designed for outside use with waterproof cases (e.g. bullet cameras) but if you need lenses of different focal lengths and especially if you need auto-iris lenses (which are best for outside because of varying light conditions) then simply moving a camera outside may not be satisfactory.

We use box cameras that are designed for outdoor use, but they need to be mounted inside a special outside housing. These housings are rainproof and can also contain a heater unit for cold winters and a fan for hot summers. Your indoor CCTV security camerasare designed for inside use only and should not be moved outside.