A building permit is required for all new construction including buildings, fences, sheds, decks, gazebos, pergolas, patios, sidewalks, driveways, irrigation systems, pools, and hot tubs. A building permit also is required for existing structures where the work to be done is regulated by a code. For example, any changes or replacement of water or gas piping, wiring, heating and central air conditioning systems, or water heaters require a permit. Work that affects the structure of any wall, door or window opening, roof element, etc., as well as replacement of windows, doors and permanent exterior coverings such as roofing and siding requires a permit. If you have any questions about whether a permit is required, please call the Building Division at 630-262-0280.