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Glazed Roof Systems

Roof Lantern & Roof Light Sizes

How big a roof lantern or flat roof light can go, the roof pitch it sits at, and the glazing and colour choices — across our Korniche and Infinity ranges.

Up to 6m × 4m (Korniche)28mm Argon-Filled GlazingPAS24 Security
Conservatory roof line icon

We supply two glazed roof ranges — Korniche and Infinity — each offering both a pitched lantern roof and a flush flat roof light. Here's what each can actually do, size- and spec-wise, based on the manufacturers' own published figures.

Korniche: size range & specification

FeatureKorniche Lantern Roof
Minimum size850mm × 850mm (square), 850mm × 732mm (rectangular)
Maximum sizeUp to 6m × 4m (rectangular), up to 4m × 4m (square/pyramid, 4 glass units)
Roof pitchFixed 25°
Glazing28mm double-glazed units, argon-filled, warm-edge spacer bar; self-cleaning glass available
SecurityPAS24 as standard
Stock coloursGloss White (RAL 9910), Matt Grey (RAL 7016), Matt Black (RAL 9005) — bespoke RAL/BS and dual-colour also available
Warranty10 years

Figures as published by Korniche for their roof lantern system — always confirm your exact opening size and spec with the trade counter before ordering.

Infinity: specification

Infinity's aluminium roof lanterns and flat roof lights are supplied made-to-measure, with slim sightlines designed to maximise glass area. Published specification:

FeatureInfinity Roof Lantern / Roof Light
Glazing28mm glazed units, 1.2 W/m²K centre-pane U-value
ColourDual colour as standard — e.g. Black (RAL 9005) or Grey (RAL 7016) outside with White (RAL 9010) inside
Warranty10 years

Figures as published by Infinity. Exact minimum/maximum order sizes for your chosen style — ask the trade counter for the full made-to-measure range before specifying.

Lantern roof vs flat roof light

Both ranges offer two distinct glazed roof styles:

  • Lantern roof — a pitched, multi-panel glazed roof that sits up from the ceiling line, giving extra headroom and a traditional conservatory-roof silhouette.
  • Flat roof light — sits flush with a flat roof for a minimal, almost frameless look from inside, with no visible pitch.

If you'd rather replace an existing conservatory roof entirely with a solid, fully insulated tiled roof instead of more glazing, see our SupaLite tiled roofs page.

Choosing a size & configuration

  • Measure your roof opening (or planned opening) width and projection before contacting us — both ranges are made-to-measure within the size limits above.
  • For very wide openings, a lantern built from multiple glass units (as on Korniche's larger pyramid and rectangular options) spreads the span rather than using one oversized unit.
  • Choose a stock colour (white, grey or black) for the fastest lead time, or a bespoke RAL/BS or dual-colour finish if it needs to match existing frames.
  • Confirm current pricing, stock and lead times with the trade counter before ordering.

Frequently asked questions

What is the biggest roof lantern size available?

Korniche's roof lantern goes up to 6m × 4m (external) for a rectangular lantern, or 4m × 4m for a square or pyramid lantern made from 4 glass units. Infinity's aluminium roof lanterns are also available made-to-measure — check with our trade counter for the exact size range on your preferred style.

What is the smallest roof lantern size available?

Korniche's minimum order size is 850mm × 850mm for a square lantern, or 850mm × 732mm for a rectangular one.

What roof pitch do roof lanterns sit at?

Korniche's lantern roof uses a fixed 25° pitch. A flat roof light (Infinity Roof Light or Korniche Flat-Glass) sits flush and isn't pitched in the same way — it's designed for flat-roof openings instead.

What's the difference between a roof lantern and a flat roof light?

A roof lantern has a pitched, multi-panel glazed roof that sits up from the ceiling line, giving extra height and a more traditional conservatory-roof look. A flat roof light sits flush with a flat roof for a minimal, frameless-looking result. We supply both as separate systems within the Infinity and Korniche ranges.

Get a size check before you order

Send us your roof opening measurements and we’ll confirm which Korniche or Infinity configuration fits.