Chimney inspections should be performed annually per NFPA 211. Chimney Inspections are required due to the nature of a burning fire. The byproducts of a fire are acidic and come in direct contact with the chimney. The contact between the masonry and acidic byproducts can damage the masonry of the chimney. This can also leave residue in the chimney which is flammable, increasing the risk of a chimney fire. Too much buildup of the byproducts of combustion can also leak into the home and cause respiratory issues.