Box Frame VS One Beam
Advantages of BOX FRAMES Over Single Beams in Large Openings
In the process of designing extensive openings or removing the main house wall (formerly the external wall into the extension area), there’s a recurrent query from builders: “Is it necessary to employ a BOX FRAME, or can a single beam suffice?”. This inquiry, posed on approximately 35% of our projects, can be somewhat vexing. The seasoned builders, accustomed to implementing BOX FRAMES for over a decade, typically proceed without questioning the design. This article aims to provide a concise overview of why BOX FRAMES are indispensable for sizeable openings or transitions into newly extended areas—an increasingly prevalent feature in contemporary extension designs.
"Why opt for a BOX FRAME when a single beam could suffice?". This question arises frequently, especially on around 35% of our projects.
Engineer’s Insight: The Necessity of BOX FRAME Designs
It’s crucial to understand the significance of BOX FRAME designs, especially when dealing with the removal of solid masonry walls. Here are key reasons:
Enhancing Lateral Stability:
Removing a solid wall impacts the building’s lateral stability system. A steel Box Frame or additional solid wall is vital to compensate for this loss and resist lateral wind loads.
Comprehensive Load Resistance:
A BOX FRAME is designed not just for vertical loads but also to withstand lateral wind and vertical loading pressures. Simple beam and pier solutions may fall short in resisting such pressures adequately.
Load Distribution:
A single beam cannot efficiently distribute loads from above, such as first-floor walls, floor/ceiling joists, roof, or loft conversions. A BOX FRAME ensures proper distribution and support, addressing potential foundation inadequacies.
It’s concerning when unqualified builders suggest a single beam, disregarding the engineer’s design. Such practices are not just negligent but deliberate cowboyism, jeopardizing structural integrity and safety. Following the correct design is paramount for a secure and compliant construction process.
Builders' Perspectives on BOX FRAME Alternatives
Certain builders tend to propose alternatives to BOX FRAME designs for a variety of reasons, often stemming from their own challenges or preferences. Here are three common rationales:
Quoting Before Design Confirmation:
Some builders quote clients before reviewing final engineering designs. When the actual steelwork requirements emerge, unforeseen costs may lead builders to seek a ONE BEAM alternative. Going back to homeowners for additional funds becomes challenging, as fixed prices are already in place, potentially compromising professionalism.
Limited Experience or Resources:
Builders lacking experience or adequate personnel for intricate installations may steer away from complex methods involving large beams and columns. The challenge of installing substantial elements requires skilled expertise and careful temporary propping methods.
Preference for Expediency:
Pure laziness can drive builders to opt for quicker solutions. Installing a BOX FRAME may be time-consuming compared to the speed of a single beam installation, leading to a preference for expediency.
In reality, a BOX FRAME is the necessary and prescribed option, supported by a qualified engineer’s design and calculations. The engineer assumes responsibility, providing detailed fabrication instructions and structural calculations for building control approval. The builder’s lack of qualification in engineering design makes their input in this area invalid, emphasising the importance of adhering to the engineered design.
Services
