No, we’re not playing checkers. However, just like strategy will help you win in checkers, it’s strategically advantageous to take care of the crown on your masonry chimney. It will make your home a winner!
So….what is the “crown” of your chimney and why is it important to take care of it?
The crown is important to the well-being of your chimney in that it can prevent water damage to your home. This concrete slab or mortar “wash” is positioned on top of the very top course of bricks on the chimney. It stops water from seeping in that flat part where the masonry structure terminates. If it is fashioned like a slab sitting on that top course of brick, it also hangs over the edge of the chimney so that water will drip down onto the roof instead of running down the sides of the chimney into the joints between bricks. A cracked or damaged chimney crown (or crown wash) eventually leads to costly repairs for damage caused by water intrusion.
How Do You Know if You Have a Cracked or Damaged Chimney Crown?
The best way to find out is with a chimney inspection performed by a CSIA Certified chimney sweep. Most cracks and damage won’t be visible from the ground, so most deterioration or damage is spotted when your chimney sweep climbs onto the roof for the inspection. Without this “bird’s eye” view, a stain on your ceiling indicating a chimney leak might be the only notification of a broken crown.
Some signs of a chimney leak from crown issues include:
A rusted damper: Rusting metal components are a sign of moisture entering your chimney. In some instances, the crown may be the culprit.
Pieces of broken flue tiles: Chips or broken pieces of tile in the fireplace or on the smoke shelf are signs of damaged or deteriorating flue lining. Water entering the chimney is one cause of such deterioration. The National Fire Protection Association recommends repairing or replacing a deteriorated flue liner before using the chimney.
Stains on ceilings or walls: Watch for discoloration (stains on ceilings or walls) or cracking or peeling on walls or ceilings. These are signs that water may be entering your chimney and seeping to the interior framing of your home. Address the source of the problem before doing any repairs to avoid fixing the same problem twice.
Crumbling mortar joints and spalling brick: Cracked or crumbling mortar joints and spalling bricks or stones (chipping or popping apart) are sure signs that water is seeping into the masonry. A broken, cracked and porous crown may be the cause. Left unaddressed, (over time) excessive moisture on or in a masonry chimney can weaken the structure (shortening its life). It is much less costly to fix a broken crown than to rebuild a chimney that is falling apart.
How Do We Fix a Broken, Cracked or Porous Crown?
That depends on the extent of the damage or deterioration and the type of crown or crown wash.
Concrete Crown: If your chimney has a concrete crown with only a few hairline cracks, a waterproof sealant may be the right solution. Larger cracks require a high bond patching material. A severely broken concrete chimney crown may need to be entirely rebuilt with the inclusion of waterproofing material.
Crown Wash: If your chimney has a mortar crown wash, it may need to be sealed with a waterproofing sealant. This will usually fill any cracks and minor holes. Advanced deterioration requires replacement of the crown wash. In addition, we include water proofing material in the mix.
Hiring a CSIA-certified chimney sweep for annual inspections is the best way to catch problems with a deteriorating crown. Early detection can prevent expensive water damage repairs.
Let our trained professionals here at Blue Sky Chimney Sweeps | Bless Your Hearth help determine overall condition, need for maintenance, and issues with functionality, and even project solutions for long-term issues. Regular inspections/maintenance can help insure there are no issues related to water intrusion through a faulty crown or crown wash.