21.5mm Pond Viewing Window – Toughened Laminated Glass UK
A 21.5mm pond viewing window is a cost-effective and reliable solution for shallow ponds and smaller viewing panels. It is commonly used in garden ponds, sleeper ponds, and decorative water features where water pressure is relatively low.
At Fusion Glass Ltd, we supply 21.5mm toughened laminated pond glass cut to size, with polished edges and UK-wide delivery.
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What Is a 21.5mm Pond Viewing Window?
21.5mm pond glass is manufactured from two layers of toughened safety glass laminated together with a structural interlayer.
This construction provides impact resistance from the toughened glass while the laminated interlayer adds an additional layer of safety.
In the unlikely event of breakage, the interlayer helps hold the glass together, making it suitable for permanent pond installations when correctly specified and installed.
Buy pond glass today!
We stock a range of common sizes in our store, but can supply any size of pond glass that you need. For bespoke orders, custom glass specifications, please get in touch via phone, email or the contact form.
Pond Viewing Window Thickness Comparison
Typical maximum recommendations. All figures assume correct installation into a suitable structural rebate with full edge support.
21.5mm
Max panel depth: Up to 400mm (16 inches)
Max panel width: Up to 1600mm (63 inches)
Best suited for: Shallow garden ponds, sleeper ponds, decorative or wildlife ponds
25.5mm
Max panel depth: Up to 600mm (24 inches)
Max panel width: Up to 2000mm (79 inches)
Best suited for: Medium-depth ponds, koi ponds, raised sleeper ponds
33mm
Max panel depth: Up to 1000mm (39 inches)
Max panel width: Up to 2000mm (79 inches)
Best suited for: Deep koi ponds, large raised ponds and projects requiring increased strength
39mm
Max panel depth: Up to 1000mm (39 inches)
Max panel width: Up to 3000mm (118 inches)
Best suited for: Very wide viewing panels, deep ponds and high-end or showcase installations
44.5mm
Max panel depth: Up to 1200mm (47 inches)
Max panel width: Up to 3500mm (138 inches)
Best suited for: Large, deep water features and specialist or commercial pond installations
Important notes:
Sizes shown are indicative and depend on panel proportions and installation method.
All pond viewing windows should be toughened, laminated and heat soaked.
Final thickness selection should always be confirmed before manufacture.
A 21.5mm pond viewing window is best suited to shallow garden ponds, decorative or wildlife ponds, and sleeper ponds with limited water depth.
It is commonly selected for smaller viewing panels where water pressure is relatively low and structural demands are modest.
For deeper ponds or wider viewing panels, thicker options such as 25.5mm or 33mm pond viewing windows may be more suitable.
Recommended Panel Sizes & Water Depths
The suitability of 21.5mm pond glass depends on both water depth and panel width.
Typical recommendations for 21.5mm pond viewing windows are a maximum water depth of up to 400mm (16 inches) and a maximum panel width of up to 1600mm (63 inches).
These recommendations assume correct installation into a suitable structural rebate with adequate support on all edges.
21.5mm Compared With Other Pond Glass Thicknesses
Compared with 25.5mm pond viewing window, 21.5mm is more cost-effective and suitable for shallower ponds, but less appropriate for wider panels or increased water depth.
Compared with 33mm pond glass, 21.5mm is designed for significantly lower water pressure and is not suitable for deeper koi pond installations.
Choosing the correct thickness is essential for safety, performance, and long-term reliability.
All 21.5mm pond viewing windows supplied by Fusion Glass Ltd are toughened, laminated, and heat soaked as standard.
Polished edges are included to improve safety and appearance, with dubbed corners supplied as standard to reduce stress points.
This specification ensures the glass is suitable for permanent pond use when installed correctly.
Pond Glass Delivery & Lead Times
Fusion Glass Ltd supplies 21.5mm pond viewing windows across the UK, providing reliable nationwide delivery for domestic and trade customers.
Typical lead times are approximately 10–15 working days from order confirmation. During busy periods, lead times may extend, so we recommend ordering well in advance to suit your project timeline.
Once your glass is ready, we will contact you to confirm delivery scheduling.
Delivery Times, Access & Offloading
Deliveries are made Monday to Friday between 07:30 and 17:30. Please ensure someone is available on the delivery day, and ideally the following day, to receive the glass.
All pond glass is delivered kerbside only. Suitable access must be available for the delivery vehicle.
Due to the weight of glass panels, at least two people are required for every 85kg of glass to safely offload. Glass is delivered unwrapped, and customers are responsible for safe handling once offloaded.
Delivery Areas & Additional Charges
We offer nationwide delivery across the UK. Additional delivery charges may apply for the following postcode areas:
AB, BT, CT, DD, DG, EH, FK, G, IV, KA, KW, KY, ML, PA, PH, PL, TD, TN23–TN30, TR
If your delivery address falls within one of these postcode areas, please contact us before ordering so delivery costs can be confirmed.
Inspection on Delivery
All pond glass must be checked immediately upon delivery before signing. Any damaged or defective glass must be reported and rejected at the time of delivery.
Order Accuracy & Amendments
Please ensure all sizes, thicknesses, and specifications are correct before confirming your order.
Cancellations or changes can be made within 48 hours of placing your order. After this period, the glass will be cut to size and no changes or refunds can be accepted.
Frequently Asked Questions – 21.5mm Pond Glass
Is 21.5mm pond glass safe?
Yes, when used within recommended size and depth limits and installed correctly.
Can 21.5mm glass be used in sleeper ponds?
Yes, it is commonly used in sleeper ponds with shallow water depth.
Do you supply custom sizes?
Yes, all 21.5mm pond viewing windows are supplied cut to your required dimensions.
Do you offer installation?
No – we are supply only, but we can advise on correct installation methods.
Fusion Glass Ltd is a UK specialist supplier of pond viewing windows, supplying glass cut to size for bespoke pond projects.
We provide honest technical advice before ordering to ensure the correct thickness is selected for your pond.
Nationwide delivery is available on all pond glass products.