Introduction
Orangeries, traditionally used for cultivating citrus plants and as extensions to residential properties, require durable roofing solutions that withstand environmental exposure while maintaining aesthetic appeal. This application note describes the implementation of a grey flat roof using the Strandek GRP (glass-reinforced polyester) flat roofing system on an orangery located in Bassaleg, Wales. The system was selected for its seamless integration, weather resistance, and long-term reliability. Strandek Flat Roofing, established in 1976 and specialising in fibreglass and single-ply systems, provided the construction services, ensuring compliance with industry standards for waterproofing and structural integrity.
The GRP system offers a lightweight, joint-free surface that eliminates common failure points associated with traditional flat roofing materials, such as felt or asphalt. This case highlights the system’s suitability for orangeries, where thermal efficiency, UV resistance, and minimal maintenance are critical.
Materials and System Description
The roofing system employed was Strandek’s GRP flat roofing, comprising:
- Base Layer: High-quality polyester resin reinforced with 600 gram chopped strand mat glass fibre for structural strength.
- Topcoat: A grey pigmented, fire-retardant topcoat resin providing UV protection and color stability. The grey finish was chosen to complement the orangery’s architectural design while reducing heat absorption.
- Substrate Preparation: OSB3 (oriented strand board) decking overlaid on the orangery’s timber frame, ensuring a stable base.
- Ancillary Components: Trims, flashings, and drip edges fabricated from GRP for seamless integration.
This system is designed for flat or low-pitch applications, with an expected service life exceeding 30 years under normal conditions, based on material durability and historical performance data. GRP roofing is impervious to water, resistant to biological growth, and capable of withstanding temperature fluctuations common in the UK climate.
Installation Procedure
The installation was conducted by certified Strandek technicians following a standardized protocol to ensure quality and safety.
- Site Preparation: The existing orangery structure in Bassaleg was inspected for structural soundness. Any debris or irregularities on the timber frame were addressed, and OSB3 boards were fixed securely to provide a flat substrate.
- Lamination Process: A primer coat of resin was applied to the decking. Layers of glass fibre matting were embedded in catalyzed resin, rolled to eliminate air voids, and allowed to cure for optimal bonding.
- Topcoat Application: The grey topcoat was applied in two layers, with the final coat providing a non-slip texture if required for maintenance access. Curing time was approximately 24 hours, depending on ambient conditions.
- Finishing and Quality Control: Edges were sealed with GRP trims, and the entire surface was inspected for defects. Waterproofing tests, including ponding simulations, confirmed integrity.
The process was completed within a typical timeframe for such projects, minimizing disruption to the property.
Performance and Benefits
Post-installation, the grey flat roof demonstrated excellent performance in initial weathering tests, including resistance to heavy rainfall and wind uplift. Key benefits include:
- Durability: The GRP system’s monolithic construction prevents leaks, with an expected lifetime of 30+ years, surpassing many alternative materials.
- Aesthetics and Functionality: The grey color provides a modern, low-maintenance finish suitable for the orangery’s glass-walled structure, enhancing natural light diffusion.
- Environmental Resistance: Impervious to algae, moss, and UV degradation, reducing long-term maintenance costs.
Guarantees provided include a 10-year insurance-backed guarantee covering materials and workmanship, underwritten by an FCA-regulated provider, and a 20-year Strandek workmanship guarantee for free rectification of any defects arising from installation. These assurances underscore the system’s reliability for residential extensions like orangeries.
Conclusion
The Strandek GRP flat roofing system, as applied to the orangery in Bassaleg, exemplifies a robust solution for modern conservatory roofing. Its combination of longevity, guarantees, and ease of installation makes it an ideal choice for similar applications. For further details on customizing GRP systems or site-specific consultations, contact Strandek Flat Roofing.