Leaks at chimney flashing let water enter the chimney structure.Leaks at the chimney sides let wind-blown rain enter the chimney structure.Damaged chimney crown lets water enter the chimney structure.Missing chimney cap lets wind blown rain and snow enter the flue.Moisture enters a chimney structure from several locations: Joints, corrosion holes along the bottom of horizontal connectors and corrodedĬhimney cleanout doors at the base of the flue. Metal components of a vent system can have rust and white acid stains at Salt stains, spalled bricks, eroded mortar joints, flaked cracks in the ceramic flue Masonry chimneys subjected to moisture damage can have efflorescent
Internal moisture (condensation) collects in cracked or separated flue tiles, Masonry, poor mortar joints and improperly designed and installed roof flashings. The flue gases are acidic in nature and ifĪllowed to condense and saturate the masonry or joints in metal flues theĭestructive results will soon be apparent.Ĭonstruction or settlement after construction and over firing or flue fires will alsoĮxternal moisture enters the chimney through cracked caps, porous Moisture is the major cause of chimney corrosion and disintegration inīoth masonry and metal chimneys. Lots of roof spillage or surface runoff was entering the base of this chimney. Our photograph at left shows a stunning waterfall flowing out of a "sealed" chimney cleanout in a basement. Chimney inspection methods and chimney repair methods are also discussed.
These articles on chimneys and chimney safety provide detailed suggestions describing how to perform a thorough visual inspection of chimneys for safety and other defects. Readers of this article should also see CHIMNEY COLLAPSE RISKS, REPAIRS. Our photo (page top) shows water pouring into a basement, coming out of the chimney cleanout during a heavy rainstorm.
We also provide an ARTICLE INDEX for this topic, or you can try the page top or bottom SEARCH BOX as a quick way to find information you need. We list the common sources of water and leaks and we include warnings for inspectors who need to examine equipment as well as the chimney itself when water or moisture leaks are detected. This article describes water leaks and moisture that damage masonry and metal chimneys and the heating appliances that are connected to them. We have no relationship with advertisers, products, or services discussed at this website. InspectAPedia tolerates no conflicts of interest.