How to design masonry support corners

What defines a corner?

Corners in Masonry Support are defined as a place where two sides meet, forming an angle which can be either internal (inside the building) or external (outside the building). Getting the design right for corners is vital as these carry more load due to their positioning and the way forces are distributed.

Internal corner:

The point at which two walls form an internal angle (generally less than 90 degrees), like the corner of a room. In these cases, the masonry line runs into the structure and turns inward.

Internal corners are generally easier to design as there is no additional loading on any individual Bracket. This means that additional corner consideration is not required.

External corner:

External Corners are the point at which two walls form an external angle (generally greater than 90 degrees).

However, unlike internal corners, external corners are more challenging to design because the masonry line extends outward, creating a cantilever effect. This cantilevering means the masonry must be supported away from the backing structure, which means careful consideration of the support brackets and fixings used is necessary

Common challenges in Corner design

Designing corners in masonry support presents several challenges, particularly with external corners. The main issues include managing the cantilever effect, ensuring adequate fixing in areas with limited concrete coverage, and working with irregular angles that deviate from the typical 90 degrees.

• Cantilever Loads -External corners often require additional brackets or PFCs to manage the cantilevered load effectively. The placement of these supports must be carefully calculated to prevent failure.
• Concrete Coverage - The location of fixings relative to the concrete slab is critical. Insufficient concrete coverage can lead to fixings failing under load, especially in areas with high shear forces.
• Irregular Angles - Not all buildings conform to 90-degree angles. When dealing with irregular angles, engineers must adjust their designs to account for the non-uniform distribution of loads.

Key considerations when designing corners

When designing masonry corners several factors must be considered. The primary challenge is managing the cantilevered masonry, particularly in external corners, which requires a robust support system to prevent failure.

Here are our tips for designing corners:

• Consider placing one additional bracket with reduced spacing.
• Is there a column to fix to? The presence of columns can significantly simplify the design as these provide additional support which reduces the loads on brackets. Try uncracked concrete and place another bracket with reduced spacing.
• When standard brackets are insufficient, especially in large cavities, consider designing with a PFC (Parallel Flange Channel). These add additional fixing points and reduce the stress on individual Brackets, however bear in mind these are often expensive.

Designing corners in masonry support is a complex but crucial step. By understanding the different types of corners and the unique challenges they present, you can create robust designs that ensure the stability and longevity of the structure. Using our checklist provided will help you to systematically approach corner design, minimising risk and optimising your designs for both safety and cost-efficiency.