The masonry industry provides great career options for talented young people. The trades offer a variety of job skills, from skilled craft instructors and journey workers to bricklayers and masonry contractors. Check out https://masonrycharleston.com/ to find the right mason for you. Many bricklayers need to install masonry support angles correctly. For example, some masons fill the void under a shelf angle with mortar, oblivious that this will crack and fall off following brick expansion.
Cold-formed angle systems are designed to suit the masonry height to be supported, cavity width, and structural fixing position. These systems comprise a folded angle fixed directly back to the support structure. These systems are available in various designs, from simple bracket angle systems to hanger systems designed to suit soldier course details. Systems can also be supplied inverted to accommodate situations where the coursing level/horizontal movement joint is above the support position. Systems can also be designed with welded serrated vertical pads for on-site vertical adjustment.
Vista designs each support angle system to suit the load, masonry height, and cavity width, ensuring the most cost-effective solution is provided for every application. Each plan will have layout drawings showing the masonry angle sections and all required fixing positions for approval before manufacture.
In traditional masonry buildings, brick walls were thick load-bearing structures. Openings in these walls, such as doors and windows, were spanned by steel lintels carefully sized by engineers to minimize masonry cracking.
The brick veneer on multi-story buildings carries the weight of the cladding above it, and this is supported by a series of angle irons known as relief angles or shelf angles. These transfer the gravity load of the bricks to the backup wall or structure and create horizontal expansion joints that allow for differential movement of the masonry and concrete frame.
Generally, these metal angles are installed regularly along the brick veneer wythe and are attached to major structural elements such as floor beams or concrete columns. They can also be used in smaller spaces, such as ribbon windows, or to support masonry cladding around columns and other specialized features.
The bricklayer is responsible for ensuring that the masonry support angle is properly sized and positioned to avoid problems. That is why a mason must be trained to install these masonry supports and properly use gauging tools.
A mason must follow the proper installation procedures to avoid problems with bowed brick. Bowed brick occurs when the brick juts out or caves around a specific wall area. It’s caused by moisture that seeps behind the masonry and either (1) warps the bricks and concrete, forcing them to push out or (2) softens the plaster or wood backing of the bricks, causing them to sink in.
The most common cause of bowed brick is a faulty masonry support. If the masonry support is not positioned correctly, it can cause the bricks to shift laterally, resulting in damage to the mortar joint and potential brick cracking. In addition, faulty masonry support can be a source of water leaks, leading to expensive repair and remediation costs. In some cases, a professional mason can repair these issues by hydraulically raising the sagging portion of the brick wall and then reinforcing it with new masonry supports.
Masonry is much more than just a pretty exterior decoration. Its walls keep the rain out of your house, support your roof, and provide a home with a solid foundation. That’s why knowing the right way to install masonry wall systems is important. Getting it wrong can lead to cracking, bowing, and sagging. Fortunately, some professional contractors can help with these problems and restore your building’s integrity.
Traditionally, masonry buildings had thick load-bearing walls which supported the structure’s weight. Openings in these walls, such as doors and windows, were often small and spanned with steel lintels. However, with the advent of skeleton frame construction, it became possible to reduce the thickness of these walls and have wide openings such as ribbon windows extending across most or even a building facade. It introduced the need for support angles, which transfer the weight of the brick veneer to the building’s structural system while allowing movement in the structure and the cladding to occur.
Shelf angles also form significant thermal bridges in a building’s wall assembly. It is especially problematic for facilities that must meet energy codes, as it can reduce a wall’s R-value by up to 50%. Austenitic stainless steel rather than galvanized steel in shelf angle is recommended as it offers far better thermal performance to minimize this effect.
Another important function of the shelf angle is creating a horizontal movement joint within the masonry veneer. It is particularly critical in masonry-clad buildings with long spans and large wall heights where the structural system experiences longitudinal and transverse movement. The movement joint created by the shelf angle enables water to exit the wall assembly and supports the flash.
In addition, the masonry shelf angle is often an element of a seismic wall system. It means they are installed regularly throughout the building to allow for seismic movement. Therefore, they must be correctly installed to manufacturers’ specifications to ensure their effectiveness. That is why it is important for a mason to attend training in the correct installation of masonry support systems.
The installer first props the angle iron against the foundation wall and fastens it to the concrete using lag screws. Now that the support angle is secure, it’s time to start laying the bricks on top of it. First, lay a course of bricks down the center of the rise and around it. Then, use your trowel to scrape a depression (called furrowing) in the mortar bed, creating a space that future bricks will fill. Continue with this process for the rest of your first course. Be sure to leave about an inch of air space at each brick. It helps to avoid the buildup of moisture in the wall.
It’s a good idea to check the angle iron with a spirit level to ensure it is perfectly vertical. Also, take the opportunity to measure and mark the height of each subsequent course against the existing bricks. Keeping these dimensions will help to ensure that the new bricks fit correctly over the existing ones, which is essential for proper building insulation.
Many problems occur with the installation of shelf angles, especially at corners. The detail below demonstrates an important point: the shelf angles should be extended to the corner. It will provide support for the masonry units and facilitate the formation of flashing at the corner. The extension of the shelf angle can be accomplished by either mitering or coped.
Another key consideration in designing a structure using angled masonry is that it should be able to accommodate movement due to thermal expansion and contraction. It’s, therefore, very important that the structural engineer properly size the shelf angle so that it can be installed to manufacturers’ specifications.
As building designers have moved toward using exterior insulation to achieve high energy standards, it’s increasingly common to see masonry connectors and shelf angles penetrate this external insulation. This practice, known as thermal bridging, can significantly affect a building’s performance. Consequently, all installers must understand how to minimize the risks associated with thermal bridging.
