What Technicians Look for During a Chimney Inspection

The National Fire Protection Association (NFPA) and other fire safety experts recommend annual chimney inspections. A yearly inspection is essential for ensuring that your chimney is not only structurally sound, but your fireplace is safe to operate. So, if it’s been more than a year since your last chimney inspection, schedule a service call with a certified chimney technician. We’ve included an overview of some of the important elements that technicians look for during a chimney inspection.

Water Leaks

Water can be very destructive to the structural integrity of a chimney, so looking for signs of a leak is a top priority of chimney technicians. There are numerous sources where a water leak can occur, such as in gaps in the bricks or mortar joints, warped flashing, and cracks in the chimney crown, for example. Signs of a water leak include stains on the ceiling around the fireplace, rusting damper, and water damage to the firebox.

Flue Obstructions

While on the roof inspecting the chimney crown and flashing, the technician will also check the chimney cap and look for flue obstructions. Anything that interferes with the venting of smoke and fumes can be a health hazard. When a chimney cap is damaged or missing, small animals, pests, and debris can clog the flue causing dangerous carbon monoxide gas to flow back into your living space. It can also allow water to enter and damage the interior masonry and rust metal components.

Masonry Damage

During a chimney inspection, the technician will examine the masonry for spalling bricks and gaps in the mortar joints that often occurs during the winter freeze-thaw effect. The masonry is a porous surface, and tiny cracks in the bricks absorb moisture. When it freezes, the water turns to solid ice causing the cracks to widen and fill up with moisture again when it thaws. The repeated cycle can be very damaging to the brickwork. Severe masonry damage can cause the chimney to lean or even collapse.

Excessive Creosote

Chimney technicians will also look for excessive creosote deposits in the flue during a visual inspection. Creosote is a naturally occurring chemical by-product of combustion, and it gets progressively more dangerous as it continues to accumulate in the chimney. When it turns into a thick, tarry, and crusty substance, it is highly flammable. All it takes is a hot ember to ignite a fire, making it the number one cause of chimney fires.

Flue Liner Cracks

In addition to a visual inspection, a video scan of the flue is highly recommended. A damaged flue liner can reduce the heating efficiency of your fireplace and allow the high heat in the chimney to spread to nearby combustible materials. A video scan can spot hairline cracks and other defects in the flue liner that is more difficult to detect with the naked eye. It can also help prolong the life span of the flue liner, saving money from a premature replacement.