1. Bricks cracking and falling off the chimney:
The problem is that your chimney bricks are absorbing water and then during normal freeze/thaw cycles the bricks are breaking apart and falling off. The solution is to apply a waterproofing to the outside of the chimney. Waterproofing will prevent water penetrating your chimney and the cracking and flaking of the bricks. A chimney professional will apply a waterproofing coating to the outside of the chimney that will reduce water penetration into the masonry by 99%, and it is also vapor permeable, which means it won’t trap water vapors when using the chimney. Waterproofing your chimney with a chimney liner gives an added layer of protection to this section of your home.
2. Water stains on the mantel or the face of the fireplace:
One possible problem could be water entering through cracks in the crown. To fix this we would, depending on the damage, either rebuild the entire crown, or seal the crown with a crown coating and sealant.
3. Water inside the firebox:
If you notice the inside of your firebox is wet after a rain storm then the most likely cause will be an uncapped chimney or chimney with an improperly sized chimney cap. The fix should be quite simple, install a properly sized chimney cap to keep water from entering the flue.
4. Water stains on the ceiling:
If stains are developing above your fireplace on the ceiling then the most common place for water to be leaking is the flashing between the roof and your chimney. In most cases the problem can be solved by applying a chimney flashing sealant. A high quality flashing sealant is excellent for use in stopping problem leaks around the base of chimneys, stacks and vents. However, sometimes the issue is too difficult to be properly sealed, and you may have to repair your chimney leak or crack.
A professional chimney sweep is usually your best choice for repairing common chimney issues.