25.5mm Pond Glass Window

The difference between the 21.5mm and the 25.5mm pond glass window is 2mm of glass per layer. At 550mm of water depth that difference is structural, not marginal. The lateral pressure a pond generates at that depth is meaningfully higher than what a 400mm pond generates, and a 10mm layer responds differently to that pressure than a 12mm layer does over time. Two layers of 12mm toughened glass, 1.5mm EVA interlayer, heat-soaked throughout.

Dedicated residential pond builds with any real ambition tend to land in the 400 to 550mm range. The 25.5mm pond glass window is what most of them need. Polished edges as standard. If you are planning a raised build from scratch, our raised koi pond guide covers everything from wall construction through to glass specification.

Width is not secondary at this specification. A pond 1,600mm across at 540mm deep puts a different load across the face of the glass than the same pond at 900mm wide, because the unsupported span is larger. If your pond runs wider than 1,600mm or deeper than 550mm, go to the 33mm. Three-layer construction, a second EVA interlayer, a fundamentally different structural response to what wider and deeper ponds generate.

Key Features

• Two layers of 12mm clear toughened glass with 1.5mm EVA interlayer
• 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

The 25.5mm sits second in the range. Below it is the 21.5mm (two layers of 10mm, suitable for ponds up to 400mm deep and 1,400mm wide). Above it are three heavier specifications: the 33mm, which moves to three glass layers and two EVA interlayers for ponds up to 900mm deep and 2,000mm wide; the 39mm for up to 1,000mm deep and 3,000mm wide using three layers of 12mm glass; and the 44.5mm at the top of the range (four layers of 10mm, three EVA interlayers, up to 1,200mm deep and 3,500mm wide). For the full depth-and-width breakdown, see our pond glass thickness guide.

Ordering

This pond glass window is made to your dimensions. Get your measurements confirmed before ordering, because once 24 hours has passed from the point of purchase, amendments and cancellations may attract additional charges. If you want to understand how specification affects price before you order, our pond glass window cost guide covers the key variables.

Delivery and Handling

Delivery is curbside by pallet or glass-carrying van. The driver brings it to the kerbside. You handle it from there, so plan for that on the day. Once installed, see our guide on how to maintain your pond glass window to keep it clear long-term. Free to most mainland UK postcodes. Excluded: AB, BT, CT, DD, DG, EH, FK, G, IV, KA, KW, KY, ML, PA, PH, PL, TD, TN23-30, TR.