Chimney Caps

An often overlooked maintenance item on many homes are metal chimney caps.  Homes with framed chimneys have flat, galvanized metal, chimney caps that serve as a roof for the chimney, and a means of flashing the flue pipe where it protrudes through the cap.   Without proper maintenance chimney caps may rust or the various seams and joints present on all chimney caps may leak, causing damage to the siding and trim on the chimney as well as possible damage to the chimney framing.

Improperly maintained chimney caps may result in decay of the siding and trim as well as severe rust stains leaching onto the underlying siding

All seams and nail heads on chimney caps as well as all joints where the flue is flashed to the cap should be inspected periodically to ensure that none of the sealants used in these areas have failed.  Any deteriorating sealant should be removed and the areas cleaned prior to re-sealing with a good quality roof sealant rated for exposure to direct sunlight.

Although  galvanized metal is rust resistant, the natural acidity of rain eventually causes all chimney caps to rust.  If no maintenance is performed on a chimney cap it may eventually rust through, causing leaks that could result in structural or mechanical damage to the home.

Rusted chimney caps not only look unsightly but the rust stains leech onto the underlying siding

Long before chimney caps rust enough to leak they have a detrimental effect on the appearance of a home.  Not only is the rusted metal of the chimney cap visible, the rust often leaches onto the underlying siding causing unsightly rust stains and giving the impression of neglected home maintenance.  Painting the siding, without addressing the rust problem on the chimney cap, does little good as the rust stains will quickly reappear.  However, with proper maintenance chimney caps can last indefinitely; while both protecting your chimney and remaining largely rust free.

Properly sealed and painted chimney caps protect the chimney and look great

If a chimney cap is rust free, maintenance is not critical, but proper care can prevent it from rusting in the future.  If it is already rusted then the rust should be stabilized before painting.  Be aware that the procedure for painting non-rusted  galvanized metal is quiet different from painting rusted metal whether or not it is galvanized.