Masonry Charleston SC combines artistic vision with precise measurements and geometric calculations. Corner poles help masons build a straight, upright wall at the correct height.
Lintels and shelf angles support masonry veneer on concrete and masonry structural systems, respectively, and are typically sized by engineers to resist deflection between points of support. These structural members also form significant thermal bridges in masonry veneer walls.
A masonry wall’s strength depends on the direction of load application. This is why lintels and shelf angles are designed to resist both shear and flexure. The design of these structural elements is based on a series of tests that determine how much force can be applied to a specific location and at what angle. The design is also based on the type of mortar used, moisture control and movement provisions.
Lintels and shelf angles are sized according to their design and can be made from metal, timber or steel. They are installed in the outer wythe of a brick wall and are a critical part of a masonry building’s structure. For this reason, it is important that these supports be built to the engineer’s specifications.
In addition to the flexural and shear strength of these structures, they must be able to withstand the compressive stresses of a wall. This is a challenge because the direction of compression in a brick wall can vary from the plane of the bed joints. This causes a stress state in the masonry that is different from what is required by the design standards. This is called masonry anisotropy.
Masonry shelf angles are located at the abutment of a load bearing brick wall and are anchored to the backup walls using wood ties or masonry anchors. The installation of these supports reduces the amount of stress on the backing walls, which can extend the life of the brick veneer. In addition, these supports can help prevent water penetration and the formation of cracks in the back-up wall.
A masonry shelf angle can be installed on a concrete or a framed backup wall, depending on the code requirements. When installing the shelf angle on a concrete backing, it is recommended that a layer of Armatherm FRR structural thermal break material be placed underneath the masonry to minimize the transfer of heat from the slab to the masonry.
Another benefit of a masonry shelf angle is that it can be pre-fabricated in the shop and delivered to the site for installation. This allows the construction process to proceed at a faster pace, which can save both time and money on the project. It also helps to eliminate the problems associated with weather delays and scheduling issues.
The durability of brick, stone and concrete masonry structures depends on the stability and integrity of the structure and the quality of installation. The use of lintels and shelf angles is an integral part of a masonry system that transfers the load from the masonry veneer to the underlying backing. When used properly, a masonry wall is capable of bearing substantial loads with little or no deflection. Lintels and shelf angles must be sized by an engineer to ensure that they meet the strength requirements of the steel design code, as well as being stiff enough to minimize masonry cracks.
Generally, masonry is attached to the underlying backing through mortar, welded wire or helical nails, and adjustable veneer anchors (see This attachment method limits movement between the masonry and the backing. Despite this, movement of the masonry may occur due to thermal changes and settlement or deflection of the underlying backing. Therefore, movement control systems are required in masonry veneer building construction to mitigate these tendencies. Movement control systems include movement joints, expansion joints and shelf angles.
Shelf angles are steel angle irons that are used above openings such as doors and windows to transfer the masonry load back to the building’s structural system. When they are not properly designed and detailed, shelf angles can cause moisture and thermal problems in the building. They also create significant linear thermal bridges that can reduce a wall’s R value by up to 50%, making it difficult for the structure to comply with energy codes.
When a building requires shelf angles, it is important that they are designed and installed in accordance with the masonry design standards set out in TMS 402/602 Code, as well as This includes ensuring that the load, cavity size and fixing type are correctly specified and that the shelf angle is positioned in the most effective position to reduce thermal bridges and minimize moisture and air infiltration. Additionally, the angle should be sized to accommodate a full cover of Armatherm FRR insulation in order to further reduce thermal transmittance through this connection.
Masonry offers a wide range of aesthetic choices for a project. Its strength and durability against the elements are often the focus, but it also provides excellent opportunities for enhancing the beauty of a building or structure. It can be designed in many styles to match architectural and interior design and is available in colors that complement most other materials. It is resistant to mold, bugs and other pests and can withstand the test of time.
It is important that architects and contractors consider the aesthetics of the masonry structure in addition to its structural performance and code requirements. Aesthetic considerations can be influenced by the color, texture and consistency of the brick/block, the color and texture of mortar and the profile and finishing of metal flashings/drip edges.
Historically, masonry buildings had thick load-bearing walls that provided substantial structural stability for the building. Openings in these walls for doors and windows were framed with steel lintels. Shelf angles were used to support these lintels and transfer loads from the masonry veneer to the main structural wall system. It was also necessary to provide a means of supporting the building’s façade at heights beyond that of the roof. The construction of these supports is complicated and requires a thorough understanding of the structural system. A meeting between the architect, general contractor and the mason can help ensure that all parties understand the requirements.
For aesthetic purposes, the long L angles of masonry supports can be left unfinished or painted for a clean, rugged look. They are also used in the masonry walls of churches, schools and other public buildings to improve the appearance and increase the strength of the walls.
An important feature of the angled masonry system is that it allows insulation to run continuously from foundation to floor line and minimize thermal bridging. This improves a building’s energy efficiency and reduces its carbon footprint. It is important that the designer and contractor work closely with the insulation manufacturer to ensure that they are using a compatible product that meets all the required specifications.
Masonry is an attractive building material that can be shaped into a wide variety of designs to match most architectural styles. It is also very durable and requires little maintenance to keep it looking great. Additionally, masonry is highly insulating and can help reduce the need for expensive cooling and heating services in Arizona.
However, the masonry itself is not impervious to weather and can become damaged by environmental factors. For example, a structure may be exposed to intense sunlight that can lead to cracking and discoloration. A thorough inspection can identify these problems and determine the necessary repairs.
One of the most common issues that can cause damage to masonry structures is the use of improper materials. For example, using brick that is not suitable for the climate in which a building is located can result in moisture damage. In addition, the use of inappropriate mortar can cause damage to the masonry walls.
To ensure that masonry is installed correctly, it is essential to work with a knowledgeable and experienced contractor. Using an inexperienced contractor can result in damage that can be costly to the owner of the property.
Another common issue with masonry is the use of inappropriate supplemental anchorage. For example, using helical or expansion anchors in place of stainless steel fasteners should be avoided. These types of anchors are not designed to support out-of-plane loads in masonry veneer applications.
An additional issue with masonry is the use of unsuitable materials in masonry supports and lintels. For instance, if a masonry wall is constructed with a lintel angle and is subject to lateral loading, the lintel should be made of steel. An alternative is a folded angle system that is designed and manufactured to engineers’ specifications to suit the specific project.
A structural engineer should be consulted to evaluate the condition of existing masonry structures. An inspection should include a close-up examination of the masonry surfaces, sounding with various tools (e.g., rubber mallet, metal hammer) to look for hidden defects and delaminations, and testing to measure water infiltration and vapor transmission.