Standardised Specification vs Bespoke Design: The Truth About GRP Flexibility
Introduction
One of the most significant advantages of Glass Reinforced Plastic (GRP) is its adaptability. Yet some engineers and specifiers still believe they must choose between standardised, off-the-shelf components and costly bespoke fabrication. In reality, modern GRP offers the best of both worlds. It can be supplied in standard sizes for quick delivery or tailored to highly specific requirements without the prohibitive lead times and costs often associated with custom manufacturing.
Understanding when to specify standard profiles and when to opt for bespoke solutions can reduce project risk, improve efficiency, and maximise performance. This article explores how GRP’s manufacturing processes, standards compliance, and design flexibility allow it to meet both routine and unique engineering challenges.
The Value of Standardised GRP Products
Standard GRP components — such as pultruded profiles, open mesh gratings, and handrail systems — are manufactured in a range of sizes and formats to comply with industry norms and project specifications. These products are typically produced to BS EN 13706 (structural profiles) or BS EN 4592 (industrial flooring), ensuring consistent performance data and load ratings.
Using standard dimensions can significantly reduce lead times. For example, Engineered Composites maintains stock of GRP gratings in common panel sizes and thicknesses, ready for next-day delivery. These standard items still offer high mechanical performance, with tensile strengths up to 240 MPa and Class 2 fire ratings under BS 476 Part 7, making them suitable for most industrial and infrastructure applications.
The refurbishment of Poole’s Wharf pedestrian and cycle bridge in Bristol is a good example of standard GRP in action. By using Deck 500 panels in stocked dimensions, the project team restored the surface quickly, minimising disruption while still delivering a tailored anti-slip finish.
Bespoke GRP Solutions for Complex Challenges
There are situations where standard components cannot address all project requirements. Site geometry, unusual loading patterns, or environmental constraints may require made-to-measure profiles or entirely new mould designs. GRP’s manufacturing flexibility makes these bespoke solutions not only possible but practical.
Pultrusion allows profiles to be produced in specific sizes, wall thicknesses, and resin formulations to meet unique structural or chemical resistance requirements. Moulded gratings can be manufactured with customised mesh patterns, colours, and surface finishes. Handrail systems can be fabricated to fit curved or multi-level layouts without compromising strength or safety compliance.
A notable example of bespoke GRP use is the Alyth Substation project in Scotland. Engineered Composites supplied palisade fencing designed to fit a complex perimeter layout while meeting stringent safety and electrical isolation standards. Custom profile dimensions and fixing details allowed seamless integration with existing infrastructure.
Balancing Standard and Bespoke for Best Value
Choosing between standard and bespoke GRP does not have to be an all-or-nothing decision. Many projects use a hybrid approach — standard stock profiles for the majority of the work, with bespoke elements manufactured for interfaces or specialist functions. This strategy can shorten installation time and control costs while still achieving a perfect fit.
For example, a rail access platform might use stocked open mesh grating for the main decking areas, while bespoke stair treads and kick plates are fabricated to match existing alignment and safety standards. By combining the two approaches, the project benefits from rapid material availability and a tailored final installation.
Standards Compliance for Confidence in Both Approaches
Whether standard or bespoke, all structural GRP should be manufactured to recognised standards. For structural profiles, BS EN 13706 specifies minimum mechanical properties, dimensional tolerances, and quality control requirements. Fire performance to BS 476 Part 7 and slip resistance to BS 7976 should also be verified through testing.
Engineered Composites provides full technical support for both standard and bespoke products, including CAD drawings, load calculations, and material certification. This documentation enables specifiers to make confident design decisions and ensures that GRP installations meet regulatory requirements.
Conclusion
GRP’s flexibility is one of its most important attributes for modern construction and infrastructure projects. Standardised components offer speed, proven performance, and cost efficiency, while bespoke manufacturing enables precise solutions to complex challenges. By understanding when to use each approach — and how to combine them — specifiers can take full advantage of GRP’s capabilities.
Working with an experienced supplier such as Engineered Composites ensures access to both ready-to-go products and fully customised solutions, each backed by technical data, compliance certification, and practical installation support.
