Two-layer pond glass windows stop being appropriate above 700mm of depth. The 33mm is where three-layer construction starts, and stepping from two layers to three is not a proportional change. An additional glass layer and a second EVA interlayer together alter how the pond glass window distributes lateral load in a way that a thicker two-layer construction cannot replicate. Three layers of 10mm toughened glass, two 1.5mm EVA interlayers, heat-soaked throughout.
The EVA bonding between each layer is load-bearing in a specific way: if the outer glass face breaks, the EVA holds the fragments in place and the inner layers continue doing their job. With three layers and two EVA bonds, both bonds need to fail before the pond glass window fails. That is not a feature of two-layer glass. For more on what type of glass is used for pond windows and how lamination changes structural performance, see our full guide.
A pond at 800mm deep needs this specification. Not the 25.5mm because it is cheaper, and not the reassurance that it will probably hold at that depth. Structural glass under continuous water pressure does not signal when it is approaching its limits. The 33mm handles 700 to 900mm of depth and up to 2,000mm of width. Outside those numbers, the 39mm is the next step.
Key Features
- Three layers of 10mm clear toughened glass with 2 x 1.5mm EVA interlayers
- Heat-soaked for additional strength and reduced breakage risk
- All edges polished to a professional finish
- Made to your exact dimensions
- Production tolerance ±3mm
- Average lead time 12 to 14 working days
- Free mainland UK delivery (exclusions apply)
Pond Glass Window Thickness Guide
For context, the 33mm sits at the midpoint of a five-product range. The two lighter specifications are the 21.5mm (two layers of 10mm, up to 400mm deep and 1,400mm wide) and the 25.5mm (two layers of 12mm, up to 550mm deep and 1,600mm wide). Heavier than this are the 39mm, which uses three layers of 12mm glass for ponds pushing 1,000mm deep and up to 3,000mm wide, and the 44.5mm at the top, a four-layer construction with three EVA interlayers for the largest builds up to 1,200mm deep and 3,500mm wide. Our pond glass thickness guide explains the full selection process if you are still deciding between specifications.
Ordering
Made to order. Supply your exact dimensions at the point of purchase. The 24-hour period after ordering is your window to amend or cancel without cost. After that, the glass is in production and changes carry a charge. See our pond glass window cost guide for detail on how thickness and size affect the final price.
Delivery and Handling
Curbside only, by pallet or specialist van. The driver does not carry the glass into the property. Plan for two people on receipt. Our pond glass installation guide covers safe handling and fitting from the point of delivery. Free mainland UK delivery applies to most postcodes. Not covered: AB, BT, CT, DD, DG, EH, FK, G, IV, KA, KW, KY, ML, PA, PH, PL, TD, TN23-30, TR.
Specifications
Specifications
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Custom built, made-to-measure glass of the highest quality.
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