A common problem to our neighbors to the North as well as here in the South, spalling occurs when water penetrates a masonry surface, including a brick chimney, and causes chipping and breaking of bricks or concrete. Freezing temperatures are what causes the damage to the masonry materials because the trapped water freezes and expands. At Bart Fireside, we know how to prevent spalling from ever happening. We have seen all sorts of mortar deterioration, and we also know that the wrong diagnosis of a masonry problem may lead to the incorrect solution, which can cause even more damage. Our customers have asked us to explain exactly what spalling is, so we would like to share some facts with you about this type of masonry damage and how to best prevent it.
The Chimney Safety Institute of America (CSIA) was not kidding when they named water as the number one enemy of masonry chimneys. Water leaking into the bricks of your chimney can do all sorts of dangerous and expensive damage to the interior and exterior of your home, including spalling, water staining of ceilings and walls, a cracked or deteriorated flue liner, and a tilted or collapsed structure of the entire exterior of your chimney. If you notice loose bricks or mortar on your chimney’s outside, water has leaked into the mortar and its joints, weakening and softening them, causing spalling. The biggest cause of spalling, however, is when that water freezes inside your masonry chimney during the winter and then thaws, causing the mortar and bricks to crack, as the freeze/thaw process makes the water inside expand.
Now that we have explained what spalling is, we would like to tell you the best ways of our preventing water leaks and spalling from occurring in your chimney structure, according to the CSIA:
- Waterproofing – Specifically made to use as waterproofing agents on a masonry chimney, these 100% vapor-permeable formulas allow the bricks and mortar of your chimney to breathe, allowing vapors to escape while still preventing water from entering. With a five to ten-year warranty, masonry waterproofing formulas should always be applied by experienced chimney technicians to ensure the application of the correct formulas, which prevents even more damage to your masonry chimney.
- Repairing a Damaged Chimney Cap or Crown – The protector at the top of your chimney suffers water and other weather exposure damage, along with your masonry chimney. Repairing damaged chimney crowns and caps and installing new ones when they are beyond repair is a crucial step to prevent spalling damage over the winter.
- Customizing the Flashing Around Your Chimney – The metal sheeting around your chimney where it meets the roof, flashing serves to seal out water from your chimney. However, if the flashing is not customized to your chimney, leaks will happen, causing water penetration and damage. Having your flashing inspected and replaced if it is ill-fitted will further prevent spalling and other deterioration.
If you have more questions about spalling or other masonry damage, contact Bart Fireside today. Our experienced staff would be happy to answer them.