Experienced home inspectors try to view the exterior of a home from all sides. From one direction everything may seem fine and from the other deficiencies may be noticed. Chimneys are difficult to view from the ground and sometimes it is not possible to access the roof or get close enough to correctly view the chimney even with binoculars. Chimneys could be brick with clay, metal, concrete liner or no liner at all. Metal chimneys are usually insulated. Stone chimneys may have liners. The liner does a few different jobs. Firstly it protects the surrounding masonry or material from premature failure by sealing the flue gasses inside from escaping into the surrounding chimney material. Secondly it provides a pathway for the gasses to be directly vented out of the building. Thirdly ease of cleaning. A smooth surface is much easier to clean than stone or textured surface. Flue liners also need to project out of the chimney by a minimum distance. Flue liners that are too close to each other may cause back drafting. During the home inspection it is not always possible to view the inside of the chimney and check on the condition of the flue liner.
Chimneys have minimum clearances which protect the building from fire and correct flue draft to get the flue gasses out of the building. A chimney may need to be extended further than anticipated to meet the needs of the draft of the flue. Anchoring of the flue stack may be required. Smoke detectors and CO detectors are recommended for all buildings and all floors.
Chimney flashings will be required and should always be installed and with care as this is a potential leak location. Chimney caps are usually masonry or metal. We (at DoubleCheck Inspections) usually suggest an anodized aluminum chimney cap when a masonry cap is found. Masonry caps have a tenancy to overtime crack and covering with an anodized aluminum usually reduces maintenance, leaks and lowers maintenance costs. A cricket is sometimes required when the slope of the roof intersects with a chimney. The cricket protects the chimney from water infiltration by diverting water from the center to the sides of the chimney. Sealant is used to seal between the flashing and roof or chimney edge.
Chimneys should be inspected every 3 to 5 years to ensure sealants and flashings are secure and bricks are clean and not deteriorating. Some notable damage to brick would be efflorescence and spauling. Efflorescence is a white dusty material that forms on the exterior of the bricks. It is one of the first signs of moisture problems. The moisture may be from damaged caulking, cap loose, exterior flashings or flue liner damage. This is why as registered home inspectors we try to find out what is going on so you can make a better overall decision on the property.
The home inspection of this chimney is looking from the upper side of the chimney down. The caulking has split and could let water rundown the side of the chimney and eventually leak into the home.
This chimney problem was only visible during the home inspection with the aid of binoculars. The masonry chimney is tilting and separating from the home. Also the mortar is missing between some bricks and the white chalking material, (efflorescence) is an indication of leaking from separated flue liners. This chimney will need to be rebuilt and properly anchored to the building.