What kind of masonry repair do I need?
We realize every fireplace and chimney system is different. That's why we always recommend hiring a qualified professional to evaluate your needs. Below, you will find a basic list just to name a few of the scenarios we run into on a daily basis. But first, in order to go over the possible repairs that you may need for your fireplace and chimney system, we will go into a few details about basic construction of a properly built masonry chimney.
When looking at your chimney from the outside, all of the brick, block, or stone work that you see on the exterior, really is just a casing for the real chimney system on the inside. Underneath all that masonry is a hollow cavity protecting the firebox and chimney flue from the outside elements. If you were to remove that beautiful brick or stone work, you would then see the infrastructure for your firebox, damper housing, smoke chamber, and the chimney flue running vertically all the way to the top.
Now, if the exterior brick or stone masonry work has become damaged or compromised over the years, you might find some interesting things with these other components that may be cause for concern. Moisture from either rain or melting snow may have leaked in alongside the masonry and the framing of your home causing some of the wood to rot or the bricks and mortar to deteriorate. If you have any cracks or gaps in your chimney flue or a damaged smoke chamber, heat, smoke, and the acidic by-products being released when using your fireplace could have literally been eating away your chimney from the inside out.
So, with all of that in mind, let's get down to our list of possible masonry and chimney repairs.
The chimney crown, sometimes referred to as a chimney wash, is the slab of concrete or mortar on the very top of the chimney. This helps keep rain and melting snow away from the masonry structure, but over the years, can become very porous or cracked, allowing excessive moisture to enter into your chimney system. This could allow potential water to damage other portions of your home, and begin to eat away at the mortar joints in between the brick or stone. Eventually, after enough water gets into the masonry, the bricks or stones will become damaged as well. In some cases, if caught early enough, the chimney crown can be repaired with a liberal coating of a wonderful product we like to use called Crown Saver. This is a brushable sealant used to repair small cracks and the general state of porousness found in chimney crowns. It creates a waterproof membrane to keep future water from entering into your masonry chimney.
In more severe cases, a simple coating of crown coat will not be enough to save your chimney crown. If a chimney crown has been damaged long enough and severely enough, we might recommend rebuilding the entire crown. Two options would be available in this case, a new chimney wash or an actual overhanging chimney crown. Both scenarios are better than a cracked and porous chimney crown, the only difference is with an overhanging chimney crown, rain water and melting snow will be able to drip off away from the rest of the brick or stone masonry.
Have you begun to notice missing or crumbling mortar in between your bricks or stone? This again is from water damage that has most likely entered through a cracked or porous chimney crown. Enough water has soaked into your chimney and caused the mortar joints to deteriorate, now the most likely fix is going to be tuck-pointing. This will require the grinding out or removal of the compromised mortar joints to allow for new mortar to be put in its place. Once the new mortar had begun to cure it is typically made smooth with a special jointing tool to make it waterproof once again.
Replacing spalling, flaking, or cracked bricks
The elements of weather are notorious when it comes to masonry. Moisture and masonry never mix well, and over the years bricks and in some cases stones, can become damaged. If your chimney damage is severe enough, you may see your bricks or stones beginning to crack, flake or spall. This is when enough water gets behind the masonry and causes the faces of either the bricks or stones to deteriorate and flake or even pop right off. In some cases, we may be able to cut out and remove the few damaged bricks and replace them with new brick.
If we come to find that none of the above repairs will be able to help your chimney because of the severity of damage, we will most likely recommend a full or partial rebuild of the chimney system. This will entail much more labor and preparation as the chimney would need to be safely demolished and lowered to an acceptable level. Once the demolition is done, we can then begin the rebuilding process.
We sincerely hope this information helps you decide if you need to move forward on an upcoming repair project. So, let's not only protect your investment, let's add value to your home all year long by improving the quality and integrity of your wood burning fireplace and chimney system with experienced and qualified masonry technicians from Element Hearth and Home.