Fixing and buying guide
KEYSTONE S/K-110 - 3600mm Standard Load Cavity Lintel
Who this lintel is for
This product is intended for builders, bricklayers, and experienced DIY customers installing cavity wall construction. It is suitable for standard residential properties and light commercial buildings where load requirements do not exceed 16 kN. If your project involves heavy loads, wide spans, or specialist applications, consult structural engineers or the manufacturer for alternative products.
- Domestic new build and renovation projects
- Light commercial buildings
- Standard cavity wall openings for doors and windows
- Projects where structural calculations confirm loads under 16 kN UDL
Sizing and compatibility
This lintel is 3600mm long, making it suitable for openings up to approximately 3500mm clear span, depending on bearing requirements and structural design. The 100mm height is standard for cavity walls and sits within the bed joint of masonry courses. The outer leaf dimension of 102mm and inner leaf dimension of 100mm are designed to align with standard brick and block thicknesses in cavity construction. Always verify your opening dimensions and load calculations before ordering, and confirm that this length is appropriate for your specific application.
- Length: 3600mm
- Height: 100mm
- Outer leaf bearing: 102mm
- Inner leaf bearing: 100mm
- Total load capacity: 16 kN UDL
Pre-installation checks
Before fixing, inspect the lintel for any damage or defects. Ensure the supporting masonry is plumb, level, and capable of bearing the lintel safely. Check that adequate bearing length is provided at each end—typically a minimum of 150mm on each side is recommended, though structural design may specify otherwise. Verify that the cavity width matches the lintel design and that both inner and outer leaves are ready to receive the lintel at the correct height. Clear any debris or mortar droppings from the cavity that could prevent proper seating.
- Inspect for damage before installation
- Confirm supporting walls are plumb and level
- Verify minimum bearing length at each end
- Check cavity width is compatible with lintel dimensions
- Clear cavity of debris to ensure full bearing
Installation and fixing
Bed the lintel on a full mortar bed on both the inner and outer leaves, ensuring it sits level and is fully supported across its entire length. Do not allow the lintel to bridge the cavity unsupported. Build up the masonry above the lintel in the normal way, maintaining proper mortar joints and cavity width. Allow adequate time for mortar to cure before applying significant loads. Once installed, the lintel becomes a structural element and must not be removed or altered without structural approval.
- Bed on full mortar on both inner and outer leaves
- Ensure level installation and full bearing length
- Do not allow unsupported bridging across the cavity
- Maintain cavity width and mortar joint consistency
- Allow mortar to cure before loading