FENSA-registered glazing experts. Made-to-measure sealed units, shipped UK-wide, backed by a 10-year warranty.
Shaped triple glazing — bespoke arched, raked, and circular TG to any spec
Triple-glazed sealed units made to any shape — arched, raked, gable-end, circular, oval, or fully bespoke. Send us a paper template, a cardboard cut-out, or a CAD spec — we'll cut, coat, and seal a triple-glazed unit to match. Pane Relief supplies shaped TG for new-build gable lights, period-property arched primaries (church-conversion, oast-house, granary refurb), bay-window curved sections, and any non-rectangular opening where the brief calls for triple-glazed thermal performance. The shaped TG line uses the same low-E coatings, argon fill, and BS EN 1279 sealing as our rectangular range — the only differences are the lead time (10-14 working days versus 7-10 for rectangular) and the per-shape engineering check we do on every order to make sure the geometry seals correctly.
Period property or self-build with non-standard lights
Listed-building consent for double glazing has been extended to triple glazing in many local authority areas where the original sashes are oversize, arched, or fan-light. We've supplied shaped TG for granary conversions, oast houses, church-to-residential refurbs, and Edwardian conservatory gables — send us a template and we'll quote it. Free measurement review on the helpline before you commit.
Email a templateArchitect, conservation officer, glazier
UKCA-marked and BS EN 1279 compliant. CAD specs accepted (DWG, DXF, PDF with dimensions). We supply a stamped engineering check per shape — useful for SAP submissions and conservation officer sign-off. Trade-tier pricing on multi-shape orders. Delivery palletised with two-person handling for any unit over 1500mm in any dimension.
Trade pricing & bulk ordersShape types we routinely produce
If your shape isn't listed, send a template — we've yet to encounter a geometry we can't seal. Lead time and price scale with complexity.
Arched (full and segmental)
Full semicircular arches, segmental arches, gothic-point arches. Common in granary, church, and Edwardian gables.
Raked / gable
Single-pitch raked tops following the gable line. Common in barn conversions and modern gable-end glazing.
Circular / oval
Porthole, bull's-eye, and decorative circular lights. Common in nautical, ecclesiastical, and arts-and-crafts work.
Trapezoid / parallelogram
Non-rectangular orthogonal shapes. Common in modern architectural glazing and underside-of-stair lights.
Pentagonal / hexagonal
Pentagon, hexagon, and other multi-sided shapes. Bespoke ecclesiastical and decorative residential.
Fully bespoke
Send a template, photo, or CAD spec. We've yet to refuse a shape on engineering grounds.
Template-or-CAD: how to spec a shaped TG order
For shaped units we need either a physical template, a photo with reference measurements, or a CAD file. Three accepted spec routes:
3 ways to spec a shape
- Physical template. Cut a 6mm hardboard or stiff cardboard template to the exact sealed-unit outline (not the daylight outline — add the 3mm-each-side rebate overlap). Mark the inside face, post or courier to us. We scan and CNC-cut from your template — most accurate route.
- Photo with scale. Photograph the existing light or opening with a steel ruler in shot for scale. Email with dimensions (rough width, height, key radii or angles). We sketch back a CAD outline for your sign-off before cutting.
- CAD file (DWG, DXF, PDF with dimensions). Architect or self-builder spec. Send the file to trade@panerelief.co.uk — we add the 3mm rebate offset and cut to spec.
Lead time and pricing
Shaped TG: 10-14 working days standard, 12-16 days with safety-glass variants (toughened or laminated). Price varies with shape complexity — a simple semicircular arch is around 40-50% more per unit than the equivalent-area rectangular TG; complex multi-sided shapes are quoted bespoke. Free template scan and CAD outline confirmation before cutting.
Shaped triple glazing — common questions answered
Q: Which shapes are feasible? Is there a complexity limit?
In principle, any closed curve or polygon can be sealed — we've supplied semicircles, segmental arches, gothic points, ogees, raked tops, parallelograms, trapezoids, pentagons, hexagons, circles, ovals, and one-off bespoke shapes from listed-property templates. The practical limits are (a) minimum radius — internal curves below 100mm radius are difficult to seal reliably; (b) sharp angles — interior angles below 30 degrees stress the edge seal at the corner and may need a chamfer; (c) maximum dimension — anything over 2400mm in any axis needs a structural review for self-weight. If your shape pushes any of these limits, the engineering team will flag it before cutting.
Q: What's the lead time for shaped TG?
Standard shaped TG: 10-14 working days. With toughened or laminated safety variants: 12-16 working days. Oversized (any dimension over 1500mm): add 2-3 days for the structural review and palletised dispatch. The first 1-2 days of the lead time is the template scan and CAD outline confirmation cycle — once you sign off the outline, the production clock starts. We can fast-track urgent shaped orders for trade clients on Net 30 accounts; call the helpline to ask.
Q: Listed-building consent — does shaped TG get approved?
Increasingly yes. Conservation officers in many local authority areas have moved from "no double glazing" to "DG-permitted in like-for-like sashes" and in some cases to "TG-permitted where the original light was already non-standard" (oversized gable, arched fanlight, etc — where the original glazing was hand-blown and the thermal performance was effectively single-pane regardless). Always confirm the spec with your conservation officer in writing before ordering. We supply a free spec-sheet for officer sign-off including the build profile, low-E coating signature, and UKCA documentation.
Q: What's the U-value on shaped TG?
Same as our rectangular TG, dependent on the build spec. 32mm shaped TG (4-10-4-10-4 argon + 2x low-E): 0.9-1.0 W/m²K. 28mm shaped TG: 1.0-1.1 W/m²K. 36mm or 44mm shaped TG for new-build frames: 0.7-0.9 W/m²K. The shaping doesn't degrade the thermal performance — the coatings, fills, and pane thicknesses are identical to the rectangular range.
Q: Can shaped TG be made in safety glass?
Yes — toughened (BS EN 12150) and laminated (BS EN 14449) are both available on shaped builds. Important constraint: toughening is shape-dependent — very acute angles, very small radii, and very narrow strips may fail the toughening process (the glass shatters in the furnace) and need laminated instead. The engineering review at the template-confirmation stage will flag if your shape pushes toughening limits and recommend laminated for the inner pane instead.
Q: How is shaped TG delivered? What about handling damage?
Shaped units ship palletised with custom timber crating and two-person handling on every order. Couriers use side-loading vehicles for any unit over 1200mm in any axis. Delivery is to the kerbside — we don't fit, and we don't carry units into property (insurance constraint). Handling damage on arrival is rare (under 0.5% of orders) but covered by our delivery insurance — photograph any damage at the point of delivery, refuse the consignment, and we'll remake within 7 working days at no charge.
Q: Do you make matching rectangular and shaped TG for the same project?
Yes — and we recommend specifying the rectangular and shaped TG together on the same order so the production batch uses the same coating run. Low-E coating signatures can vary 2-3% between production batches; ordering matched together eliminates the risk of a visible colour-cast mismatch between the arched gable and the rectangular casements either side. Multi-piece project orders qualify for trade-tier pricing even on retail accounts.
Q: What documentation comes with shaped TG?
Every shaped TG unit ships with the same documentation as rectangular: UKCA mark, BS EN 1279 compliance statement, 10-year edge-seal warranty, 5-year coating warranty. Available on request: Declaration of Performance (BS EN 1279-5), stamped engineering review of the shape geometry, BFRC equivalent rating worksheet (the shape itself doesn't have a BFRC rating; the equivalent rectangular U-value applies), and conservation-officer spec sheet with all relevant test references.
Related guides and specifications
Send a template — we cut, coat, and seal to your shape.
Email trade@panerelief.co.uk with a paper template or CAD file. Or call 0117 330 3057 (08:00-18:00 Mon-Fri) for spec advice.