Steel Lintel Calculator

Lintel size depends on the opening width, wall type, and load above. For standard cavity walls: up to 1200mm openings use standard duty lintels, 1200-2400mm use medium duty, and over 2400mm require heavy duty or structural calculations. The lintel length equals the opening width plus bearing at each end (typically 150mm each side).

For openings up to 900mm, minimum bearing is 75mm each end. For openings over 900mm, minimum bearing is 150mm each end. For heavy-duty applications or openings over 3000mm, 200mm or more may be required. Always follow the lintel manufacturer's installation guide and Building Regulations.

Yes, if you are creating or enlarging an opening in a load-bearing wall. Building Regulations approval covers the structural adequacy of the lintel, the bearing arrangement, and the overall stability of the wall. For internal non-load-bearing walls, Building Regs may not be needed but check with your local authority.

A lintel spans an opening in a wall (window, door) and supports the wall above. A beam supports structural loads such as floors and roofs, often spanning across a room. Beams are typically larger and carry greater loads. For openings over about 3 metres, a structural steel beam (RSJ/UB) may be needed instead of a standard lintel.

Yes, but steel lintels have advantages for cavity walls: they incorporate insulation to reduce cold bridging, they are lighter and easier to install, and they come in profiles that support both leaves of a cavity wall. Concrete lintels are cheaper for simple solid wall openings and internal walls.

Key steps: 1) Support the wall above the opening with props and needles, 2) Remove brickwork/masonry to create the opening, 3) Ensure bearing surfaces are level and solid, 4) Place lintel on bed of mortar on bearing surfaces, 5) Check level, 6) Build brickwork above, 7) Remove temporary supports after mortar has cured. Always follow manufacturer's instructions.