A steel lintel requires a minimum end bearing of 150mm on each side of the opening. It should be fully bedded on mortar and levelled perfectly across its length and width to ensure the load is safely distributed down the surrounding masonry.
Structural Support and Installation Guide for Steel Lintels
Steel lintels provide essential structural support across window and door openings, transferring the vertical load safely to the surrounding walls. They sit horizontally over an aperture, directly bearing the weight of the overhead masonry, such as bricks and concrete blocks, to prevent the structure from sagging or collapsing under heavy pressure.
These supports are manufactured using galvanised steel to offer excellent load-bearing capabilities and long-term resistance to corrosion. During installation, they require a minimum 150mm end bearing on both sides, firmly bedded into place using a mortar mix made with standard building cement to ensure a level and secure fit. To manage moisture and protect the building envelope, a damp proof course is routinely installed across the top of the lintel, directing any internal water outwards and preventing damp from penetrating the inner walls.
The straightforward profile of these supports allows for easy handling and accurate placement, ensuring compliance with general building regulations. Their versatility makes them suitable for cavity, solid, and timber frame constructions, adapting readily to different architectural layouts. As the masonry continues upwards from the lintel, the surrounding structure can be further stabilised using wall ties embedded within the mortar joints, tying the inner and outer leaves together for a robust and cohesive wall setup.
Steel Lintels FAQ's
A steel lintel should never be cut, drilled, or modified to fit a specific space. Altering the structural integrity of the steel will compromise its load-bearing capacity and void any manufacturer warranties. It is essential to measure the opening carefully and purchase the correct size.
Yes, temporary propping is generally required during installation to prevent the lintel from rotating or tilting before the mortar has fully cured. A horizontal timber board is typically placed beneath the lintel, supported by acrow props at regular intervals until the masonry above is completely stable.
To prevent moisture ingress, a damp proof membrane must be installed directly over the lintel within external cavity walls. The membrane should be turned up at the edges and sloped slightly to direct any trapped water outwards, keeping the interior structure completely dry.
The correct choice depends on the width of your wall cavity and the load it needs to carry. You will need to measure the outer leaf, the cavity width, and the inner leaf to find a matching profile. Always check the safe working load tables provided by the manufacturer to ensure the lintel can safely support the masonry, floor joists, and any roof loads above the opening.