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There is more to caring for a chimney than just seasonal cleanings. Many homeowners have the misconception that all they have to do is clean their chimney at the beginning and end of the burning season. Don’t get me wrong that is a great start! However there is more to it than that. To care for a chimney properly you will need to have it inspected annually, clean it regularly, repair it as needed, and prevent damages from occurring.

The Importance of Masonry Chimney Inspections

When you own a home that has a masonry chimney you have to think about maintenance beyond just regular flue cleanings. The structure of the chimney needs to be inspected on an annual basis. This includes all the way from the tippy top of the chimney crown and the way to the very bottom. When you are doing an inspection, be very thorough noting every crack or chipped brick. Inspect the portions that are indoors and in the attic as well. If there is a leaking problem around the base of the roof portion of the chimney you will notice it in the attic first, so cover all areas of the chimney. Ignoring the chimney inspection can result in detrimental damage to the masonry chimney. Costing you more than what the products to protect or repair would have. Treating cracks and other imperfections will help to prevent further damage from occurring, which in turn will help to keep repair costs to a minimum for you. It is always better to be proactive and take precautions than to wind up in a bind during the middle of a heating season.

Repair a Cracked or Chipped Chimney Crown

Today we are going to cover repairing the chimney crown. If during the inspection process you notice that the chimney crown is cracked and chipping away this is not a good thing. It should be repaired before the temperatures drop. If water was to get into the cracks and ice over it will just continue to make the cracks worsen or start to break away from the chimney. To repair the chimney crown it will need to be sealed with a waterproof sealant.

Why Choose CrownSeal

We recommend using CrownSeal by ChimneySaver to seal any imperfections in the chimney crown. CrownSeal is specially formulated to repair and protect the chimney crown from water intrusion. The CrownSeal will form a flexible waterproof membrane that dries to a natural concrete/mortar appearance. This product can be used anywhere that a long-lasting exterior waterproof sealant is needed, including masonry walls, stucco repair, masonry window sills, and more. CrownSeal can be used as a bonding mortar to replace very loose bricks as long as the brick is solid and not crumbling. You can use small amounts of mortar dye to color the CrownSeal as well.

Review of CrownSeal Advantages:

  • A Manufacturer’s 10 Year Limited Warranty
  • Remains Permanently Flexible
  • No bonging agent is required
  • Dries to a Natural Concrete/Mortar look
  • Comes Ready to Use
  • It is Environmentally Friendly

How to Apply CrownSeal

  1. Preparations: The chimney crown surface to be coated must be structurally sound, not loose. It must be clean and dry. Lay down drop cloths or plastic sheets to protect the roof from inadvertent spills. Brush the chimney crown surface with a stiff poly brush to remove loose particles. Any large cracks or voids can be filled with fast setting patching cement or premium grade, siliconized, acrylic latex caulking. CrownSeal may be applied over top of the caulk before it cures as the siliconized, acrylic latex caulk will cure underneath of the CrownSeal.
  2. Begin by using a spray bottle to lightly mist the crown with water. Do not flood. Misting with water will help to cool a warm chimney crown as well as improve both the penetration and adhesion of CrownSeal.
  3. Apply the CrownSeal to the chimney crown with a trowel, putty knife, or 1/4” square notch trowel. Spread to a uniform thickness of no less than 1/8”.
  4. Lightly mist CrownSeal with water and smooth out trowel marks using a 4” nylon paint brush. Make sure the bases of flue tiles are thoroughly coated.
  5. Drying time: Temperature, humidity, thickness of application and how porous the chimney crown surface is will all affect the curing time of the product. In warmer weather, curing time will be approximately 6 to 8 hours. In cooler weather, it may take 24 to 72 hours to cure.
  6. Protect area from rain or other moisture source until cured. A plastic covering may be used for protection if rain fall is expected. If an application is exposed to a heavy rain before curing, remove any product runoff with a stiff brush and rinse with water.
  7. CLEAN UP!!! Remove CrownSeal from tools immediately after each use by scrubbing with a scrub brush and water. Rinse thoroughly.

Tips to Remember:

  • Surface and air temperature should be a minimum of 45°F but not greater than 95°F at the time of application.
  • Do not apply if temperature is expected to drop below 45°F within a 24 hour period.
  • Do not apply to frozen or frost covered surfaces.
  • Do not apply to wet or water saturated surfaces and/or when rainfall is expected within 24 hours unless adequate protection with a polyethylene film or its equivalent is provided.
  • Wear protective gloves and chemical splash goggles when applying or cleaning tools.
  • Coverage Expectations: At 1/8” thickness, CrownSeal will cover 14-18 sq. ft. per gallon. At 1/4” thickness, CrownSeal will cover 7-9 sq. ft. per gallon, depending on texture and porosity of surface.
  • CrownSeal is most effective when applied at a thickness of 1/8”-1/4” (1” max.).
  • On large applications, complete one half of the crown at a time.
  • Keep container closed when not in use.
  • For faster curing in cool weather, do not mist crown with water before application.
  • Thinner films such as 1/8 inch will cure faster; thicker applications will cure more slowly and require longer protection from rain.
  • To clean inadvertent spills from roofs, etc., remove excess and clean remaining CrownSeal with a stiff nylon scrub brush and water.