Concrete Lintels

What Are Concrete Lintels?

Concrete lintels are crucial structural components used to span openings in walls, such as those for doors and windows, by supporting and transferring the weight of the structure above them to the adjacent walls or supports. 

Typically composed of reinforced concrete, these lintels integrate steel reinforcement bars (rebar) within the concrete matrix to enhance tensile strength and resist bending forces. They are engineered to bear significant loads and distribute them evenly, preventing potential sagging or structural failure. 

What Are Prestressed Concrete Lintels? 

Prestressed concrete lintels offer significant advantages over conventional reinforced concrete lintels, including the ability to span greater distances and support heavier loads. This enhanced performance is due to a specialised pre-compression process that helps them better handle tensile stresses, resulting in increased efficiency and durability.

During the manufacturing process, high-strength steel cables or rods, known as tendons, are stretched and anchored within the concrete before it sets. Once the concrete has cured, the tension in these tendons is released, creating a compressive force within the concrete. This pre-compression counteracts the tensile stresses the lintel will face in service, improving its resistance to bending and cracking.

In addition to their superior strength and rigidity, prestressed concrete lintels offer excellent fire resistance and versatility in surface finishes. Unlike steel lintels, which can be less aesthetically flexible, concrete lintels are often used in visible areas and can be easily painted or finished to blend with the surrounding architecture.

Where Are Concrete Lintels Used?

Concrete lintels are most commonly applied in masonry or brick structures. Most typically they are applied above doors and windows; structures which cannot withstand large loads on their own. Concrete lintels are employed in various building scenarios, including:

• Door and Window Openings: Placed above to support the structure’s weight.
• External Doors: Provide load-bearing support for entryways.
• Internal Partitions: Used to reinforce internal wall structures.
• Load-Bearing Walls: Essential in maintaining stability.

Concrete Lintel Benefits

• Durable and Hard-Wearing: Long-lasting and resistant to wear.
• Cost-Effective: Provides a budget-friendly solution for structural support.
• Fire-Resistant: Offers excellent protection against fire.
• Insulation Properties: Helps to reduce thermal bridging and improves energy efficiency.
• Prestressing: Enhances performance under load by placing a high compression load on the beams.
• Decorative Finishes: Available in various finishes for aesthetic purposes.

Concrete Lintel Installation Considerations

When installing concrete lintels, it is important to use the proper type of anchors, such as mechanical anchors, and to make sure that the lintel is properly supported. 

Following current building regulations, a flexible damp-proof course or cavity tray must be installed in external walls whenever necessary.

Furthermore, the lintel should be levelled on mortar, used in the correct orientation and securely anchored to the wall. To ensure that you correctly install your lintels, please refer to the manufacturer's installation instructions and contact a technical department, if necessary.