This guide provides essential information for builders and contractors using the Catnic CN71A Steel Lintel, a robust solution for external solid wall applications. Its primary benefit is immediate support for wet masonry loads, significantly streamlining construction. However, precise load calculations and adherence to installation guidelines are crucial for maximizing its structural integrity and long-term performance.
Duplex Corrosion Protection: Manufactured from galvanized steel and then powder-coated, offering superior resistance to rust and environmental elements.
Immediate Load Bearing: Engineered to carry a full load of wet masonry as soon as it is installed, speeding up construction timelines.
Anti-Twist Box Profile: Its unique box profile design prevents twisting, warping, or distortion under heavy loads, ensuring structural stability.
Built-in DPC (Damp Proof Course): Integrates a DPC to prevent moisture penetration, contributing to the building's durability and reducing the need for separate DPC installation.
Integral Insulation: Features built-in insulation (Cougar open back profile), which helps improve thermal performance and energy efficiency.
Reduced Material Use: Designed to save on brickwork and insulation, offering a more efficient construction method.
Easy to Use: The design simplifies handling and installation for qualified professionals.
Standardized Lengths: Available in increments of 150mm up to 3000mm, and 300mm for lengths 3000mm-3600mm, facilitating specification.
Supports wet masonry immediately, accelerating construction.
Excellent corrosion resistance with galvanized and powder-coated finish.
Box profile prevents twisting and distortion under load.
Integrated DPC and insulation simplify installation and improve performance.
Designed for high-performing answers in difficult openings.
Suitable for solid wall construction or narrow cavity walls (from 70mm).
Load limits decrease as the structural opening increases, requiring careful calculation.
Requires a minimum 150mm bearing at each end, which must be accounted for in design.
Specifically designed for external solid walls, limiting its application to other wall types.
Heavier than some alternative materials due to steel construction.
Installation requires precision for optimal performance and safety.
Supports wet masonry immediately, accelerating construction.
Excellent corrosion resistance with galvanized and powder-coated finish.
Box profile prevents twisting and distortion under load.
Integrated DPC and insulation simplify installation and improve performance.
Designed for high-performing answers in difficult openings.
Suitable for solid wall construction or narrow cavity walls (from 70mm).
Load limits decrease as the structural opening increases, requiring careful calculation.
Requires a minimum 150mm bearing at each end, which must be accounted for in design.
Specifically designed for external solid walls, limiting its application to other wall types.
Heavier than some alternative materials due to steel construction.
Installation requires precision for optimal performance and safety.
The Catnic CN71A Steel Lintel is a high-performance solution specifically engineered for demanding external solid wall applications. Its key advantage is the ability to immediately support the full load of wet masonry, which drastically reduces curing times and speeds up the construction process. The unique box profile is crucial for its anti-twist performance, ensuring the lintel remains stable and true even under the substantial weight of fresh brickwork or blockwork. This makes it ideal for creating openings in solid walls or narrow cavity walls (down to 70mm), where structural integrity is paramount. For example, during the installation of a new window or door opening in a traditional solid brick house, the CN71A allows bricklayers to continue working above the opening without extended pauses for the lintel to cure. The duplex corrosion protection, combining galvanization with a black powder-coat finish, ensures long-term durability in external environments, making it suitable for all weather conditions. Its built-in DPC and integral insulation further contribute to the overall building envelope performance, reducing the need for separate components and ensuring a continuous thermal and moisture barrier. Users will find it particularly effective in scenarios where speed and structural reliability are critical.
Prepare the Opening: Ensure the structural opening is clean, level, and accurately sized to accommodate the lintel with sufficient bearing.
Ensure Adequate Bearing: The lintel must have a minimum of 150mm bearing at each end on sound masonry. This bearing is critical for the lintel's Safe Working Load (SWL).
Positioning: Place the lintel centrally over the opening, ensuring the DPC (damp proof course) is correctly oriented to prevent moisture ingress. The 'Cougar open back profile' (integral insulation) should face upwards or inwards depending on the specific wall construction details and insulation strategy.
Masonry Placement: Begin laying masonry on the lintel's top flange immediately. The design allows for a full load of wet masonry upon installation, but ensure even distribution.
Propping (Optional): While designed for immediate wet masonry loads, for very wide spans or specific site conditions, temporary propping may be used for additional stability during the initial stages of masonry curing. Always refer to specific project engineering advice.
Wall Types: Primarily designed for external solid wall construction or narrow cavity walls with a minimum 70mm width. Not suitable for standard wider cavity walls without specific engineering assessment.
Masonry: Compatible with standard brick, block, and stone masonry.
Load: Suitable for Uniformly Distributed Loads (UDL). Always consult Catnic load tables for the specific SWL based on your required span and wall type.
Inspection: Regularly inspect installed lintels for any signs of damage, corrosion, or deflection, especially during routine building maintenance.
Cleaning: The powder-coated finish provides excellent protection. Clean with mild soap and water if needed. Avoid abrasive cleaners or tools that could damage the coating.
Damage: If the powder coating is scratched or damaged during installation, repair with a suitable exterior-grade paint to maintain corrosion protection. For significant damage or signs of structural compromise, consult a qualified structural engineer.