Inspection Unit 3D

Types of Inspections

Chimney Inspections

Chimneys are a special concern. Inspection consists of looking at the chimney exterior, then in the flue(s) from the top and the bottom. First, look at the exterior of the chimney and how it is positioned by the house. Keep an eye out for two key problems. First, chimneys pull away from the building creating a gap that bats in particular love to exploit. Second, the slate part of the chimney often slides away from the building creating a gap that squirrels reportedly love to use. Some have even seen gray squirrels chew an opening if the slate is loose.

Next, you will need to investigate the inside of your chimneys. But first, ask your client how many fireplaces he has. Each fireplace and furnace will have its own flue. Don’t confuse chimneys with flues. Broken cap and note the missing cap on the second flue. Photo by Stephen M. Vantassel A chimney can have more than one flue. (Note the top photo: just because one flue is capped doesn’t mean that all the flues are capped, Photo by Stephen Vantassel). (Note the second photo: these are double walled metal flues, Photo by Stephen Vantassel). Sure the inside flue is screened but notice that the exterior tube is not.

Double walled flues. Photo by Stephen M. VantasselMany birds and squirrels do fall in between the two pipes). Note that they look screened. But there is a gap at the base that allows birds etc. to squeeze in and become trapped.  Make sure you ask if there are any fireplaces in the basement. People tend to forget how many fireplaces they have if they don’t use them.

Always inspect a chimney from the top first. If it isn’t a bent flue, it can save you from looking up from the bottom. As you look down the flue take a moment and look for smudge marks which will alert you to previous and/or present raccoon occupation.. When you are inspecting from the top of the chimney, look for spider webs in the flue. The presence of spider webs will tell you that nothing has gone down this chimney in a while. Even though raccoons rarely enter active furnace flues, it has been known to happen. So pay attention. Occasionally, you will even find bits of fur caught in the cracks of rough flue tile. Always inspect a chimney from the top first. You don’t want to be surprised by an animal when you open the damper.

Don’t take the client’s word that the flues have been screened. Screening rusts through or blows off. These homemade screening jobs are usually illegal as they don’t allow enough clearance for exhaust. (See picture. The black cap is the right way. The hardware cloth is the wrong way. Photo by Stephen Vantassel). Make sure your eyeballs do the job. A chimney can have more than one flue and not all flues can be seen from the ground as demonstrated by the first image on the page. How not to protect chimney flues. Photo by Stephen Vantassel

Checking fireplaces on the inside: Since old fireplaces are full of soot etc, don eye and respiratory protection. (You will also need your reflecting mirror so you can look behind the damper. Photo by Stephen Vantassel) If you must open the damper, always open the damper slowly and no more than an inch at first. But first don your HEPA filter respirator and goggles to protect your lungs and eyes from falling debris. Shine your flashlight into the crack and look for any paws and fur. Listen for noises. You don’t want to be surprised and have a soot-covered squirrel run around your customer’s picture perfect white-carpeted living room. I like to prime the flue with a propane torch. This way the draft is going up when I crack the damper. I like using propane because it doesn’t create smoke and the flame can be turned out immediately. You won’t burn the animals if you keep the flame away from the damper. The smell of the propane has the added advantage of spooking animals like raccoons that will often begin climbing the chimney away from the damper. Although during most of your inspections, you will not find animals, here are some rules of thumb regarding noises emanating from a chimney: 1. Scratching, think squirrel 2. Fluttering, think bird 3. Chirping, think raccoon 4. Grinding noise, think chimney swift (especially if the chimney is not lined with tile.) Don’t be surprised if other animals are found in the chimney. I personally have found a duck and an owl. So the list of animals can get pretty strange. Stainless steel multiflue chimeny cap. Photo by Stephen M. Vantassel

Finally, recommend that the customer have the chimney secured with a professional and code compliant chimney cap. But NEVER, NEVER secure the chimney unless you are certain that there are no animals inside. The image at right shows a professionally capped chimney with a cap known as a stainless steel multiflue cap.  (Photo by Stephen Vantassel)


Stephen M. Vantassel, Wildlife Removal Handbook Rev. (Stephen M. Vantassel, 1999).

Stephen M. Vantassel. Wildife Damage Inspection Handbook 3rd. ed. (Lincoln, NE: Wildlife Control Consultant, 2012).

©2005 Stephen M. Vantassel

Unit 4 Lesson A