Chimney flue damage
There are a few things you need to take into consideration when inspecting a chimney flue. A damaged flue can lead to carbon monoxide infiltrating in the house and poisoning the inhabitants. Paying a professional to inspect the flue for you is recommended if you do not think you can handle it.
Inspecting the chimney flue at least at the beginning and ending of the fireplace use season if enough to detect any problems with the flue. Cleaning the creosote buildups and repairing a few cracks is much better and cheaper than rebuilding the whole chimney because of untreated issues.
- Safety glasses and dust mask
- Drop cloth
- Wire brush
- Shop vac
- Extension cord
The chimney must be inspected while it is cool and after cleaning the firebox and ash pit.
Signs of damage
Regardless if your chimney flue is made out of sheet metal, clay tiles or cast-in-place concrete, you can easily detect signs of damage. If the flue is made out of concrete or clay, look for surface cracks that may let toxic gases pass through and enter the house. In the case of metal flues, look for signs of warping or gaps in the joints or liners that smoke may pass through. In each case, the creosote buildups will occur. Creosote is a byproduct resulted when burning fuel in the fireplace. Such buildups can ignite and cause a fire hazard. Avoid that by cleaning the flue and leaving no more than 1/8 inch thick creosote left. Black and smooth creosote is more dangerous than brown flaky creosote.
Angle of inspection
You must inspect the chimney from all angles. Clean the fireplace, put on protective goggles and look up the chimney to check for signs of damage or other issues. Make sure the damper works fine. Then, get a ladder and get on the roof so that you can inspect the chimney from the top also.
Clean what you can
To clean the chimney, use a wire brush and a vacuum. If your chimney has a smoke shelf, it will catch any pieces of dirt that fall down when you brush the chimney. Use the vacuum to clean the smoke shelf.
If by any means you fail to properly inspect the chimney or find any serious signs of damage, you must hire a professional chimney sweeper. He will inspect the chimney and tell you what problems need fixing and will also tell you the cause of these problems that may either be faulty construction or foundation shifting. If this is the case, the chimney will require rebuilding.