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Repairing Mortar Joints

Over time, exposure to rain and cold weather can degrade bricks and mortar. Any damage to masonry should be addressed right away. Failure to do so can lead to a leaning chimney that collapses.

Knowing what to look for can help homeowners spot problems early and get them repaired quickly. This article covers some of the most common chimney repair issues, from gaps in mortar to spalling. Contact Baltimore Chimney Repair now!

Mortar joints between bricks are one of the most vulnerable parts of a masonry wall or chimney. They can become damaged due to exposure to weather and moisture. Damaged mortar can lead to cracks, gaps, and crumbling of the masonry surface. It can also reduce the structural strength of the building or chimney. The best way to prevent further damage is by repairing damaged mortar joints as soon as possible.

Repairing old, damaged, or crumbling mortar is a process known as tuckpointing. The tuckpointing process involves chiseling out the old mortar and replacing it with fresh new mortar. While tuckpointing can be done by the homeowner, it is often best left to professionals. Professional masons are trained to evaluate and repair masonry structures, and have the proper tools for the job.

The first step in tuckpointing is to assess the mortar damage. Inspect the mortar joints for loose or crumbling bricks and for signs of water penetration or decay. A sledgehammer and cold chisel should be used to chip away the damaged mortar, while taking care not to damage the surrounding bricks. After the old mortar has been removed, a stiff brush should be used to clean the joint. Then, the joint should be lightly misted with water to dampen it. This step is important because dry brick sucks the moisture out of fresh mortar, preventing it from curing properly.

Next, prepare the new mortar mixture. Pour the ready-mix mortar into a bucket and add water gradually to achieve a consistency that is workable. Make sure to mix well and that there are no lumps. When the mortar has reached the right consistency, use a brick trowel to fill the old mortar joints. Start by filling the vertical mortar joints, then move on to the horizontal joints. Fill deep joints in layers, allowing each layer to set before adding more.

After the new mortar has been filled, let it set for about 24 hours. Then, use a flat tip screwdriver to “dress” the mortar joint to give it its final shape and match it to the existing color of the brick. Then, allow the mortar to set again for another 24 hours.

Brick Degradation

Brick walls and chimneys can become damaged by a wide range of factors. In some cases, deterioration can be so severe that the structure needs to be rebuilt. While some deterioration is inevitable, there are some steps that can be taken to limit the damage and extend the life of a brick wall.

Moisture is a leading cause of brick degradation. The material is porous and will absorb water over time, eventually becoming saturated. This saturation leads to damage, dampness, and discoloration. It’s important to inspect brickwork regularly for moisture issues and address them promptly.

Look for signs of water damage such as a white, dusty powder that appears on the surface of bricks. This is called efflorescence, and it’s caused by salt deposited on the brick from evaporated water. While this isn’t harmful, it can be unsightly and indicates a problem with the structure.

Other signs of moisture damage include cracks, buckling, and spalling. Cracks in brick are a sign of structural movement and may require underpinning or piering. Buckling and spalling are both indicative of water damage, and should be addressed immediately.

Keeping your building free of organic growth, including plants, will also help prevent moisture problems. These plants, such as ivy and other climbing vines, can block water flow and lead to leaks and dampness in the wall. If the plant isn’t removed, it can even lead to structural damage affecting the roof and walls.

Poor mortar consistency or coverage is another common reason for brick deterioration. In these cases, the bricks are more prone to damage and disintegration due to their inability to withstand abrasions or weathering. It’s crucial to work with a contractor who has masonry construction experience to ensure the mortar is applied correctly.

When repairing cracked or crumbling brick, mist the area with water before applying the new mortar to improve adhesion. Once the mortar is dry, use a tool to match the shape of the existing mortar joints and then use a technique known as feathering to blend the new and old mortar lines. Mist the repaired area daily for three days to ensure it remains moist and helps the mortar cure.

Leaks

Chimney leaks are often the result of a deteriorating chimney flashing. The flashing is the metal material that bridges the gap between a chimney and its roof, whether it’s made from shingles or another type of roofing. The flashing can deteriorate with age, or it can be damaged by harsh weather conditions like high winds and intense heat. The flashing should be properly layered with the shingle to protect against water penetration, and it should be adequately fastened with masonry screws or nails.

Depending on the severity of the chimney flashing damage, this can be a relatively easy repair for homeowners to make themselves. First, they’ll need to take a look at the problem from the ground to see where the water is coming in through the brick. Using a garden hose to soak a small section of the chimney can help a homeowner discover where the leak is coming from. A water test can also reveal if the leak is caused by a different issue, such as a failing masonry crown or cracked tuckpointing.

When a leak is found, the next step is to climb on the roof and look for the source of the leak. If the leak is from a flashing that’s damaged or not properly layered, this can easily be repaired with new roofing cement and masonry screws. Alternatively, a flashing replacement can be installed for more durable protection.

Some types of flashing deteriorate more quickly than others, so it’s important to check the condition of the flashing regularly. A qualified chimney service can replace the flashing and ensure it’s properly layered to protect against rain penetration.

Whether it’s a cracked tuckpointing or a leaky chimney, these issues can compromise the structural integrity of a fireplace and lead to costly repairs down the line. Homeowners should look for water stains, musty odors, or other signs of a chimney leak, and call a professional to perform repairs promptly to mitigate these problems before they get worse. This way, homeowners can enjoy the warmth and ambience of their chimney again without worrying about the safety or integrity of their home’s masonry.

Rust

When you see rust in your chimney, it’s a sign that it needs some attention. Chimney rust isn’t just unsightly, it can also be dangerous. It can damage the inside of the flue, which could lead to chimney fires. Rust can also cause the chimney to leak. Chimney rust can be repaired in several ways, including by repointing or tuckpointing. Repointing is the process of repairing the mortar joints, while tuckpointing involves filling in and patching the bricks to give them a more polished appearance. Both methods can help to reduce leaking and increase the efficiency of your chimney.

When your chimney is leaking, it can cause serious damage to your home and its structure. It’s important to keep up with your chimney maintenance and hire a professional chimney repair contractor when needed.

Another common chimney problem is carbon monoxide leaks. Carbon monoxide is a poisonous gas that can build up in your house if it isn’t vented properly. Carbon monoxide can also enter your home through damaged chimneys, causing severe health problems for your family.

While masonry chimneys are built to be incredibly durable, they can still suffer from structural problems from time to time. Cracks in the crown or spalling bricks can be a big problem for homeowners, but fortunately, these issues are easy to fix. A professional chimney repair contractor can use a special cement to repair these issues and restore the integrity of your chimney.

Chimneys with cracked or crumbling bricks should be repaired as soon as possible. These issues can lead to expensive repairs, or worse, they can put the safety of your home and family at risk. Chimney bricks can crumble for many reasons, including harsh weather conditions and the type of mortar used during construction.

If you notice cracks in your chimney, it’s important to get them repaired right away. A professional chimney repair technician can seal these cracks using a special cement, which creates a watertight barrier to prevent further damage. Chimneys with larger cracks may need repointing or relining. Relining is a more extensive repair option, but it’s often necessary if the chimney flue is damaged or shows signs of leaks.