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A self-supporting, glazed barrel vault.

Features and benefits:

  • The system has an'cascade' internal water management system.
  • Can be glazed with solid or multi-wall polycarbonate, giving high thermal performance for Part ‘L’ compliance.
  • The ends can be terminated with vertical glazed screens, or can simply abut an adjoining structure.


  • Maximum wind loading to BS 6399:1: 1.5 kPa.
  • Maximum imposed loading to BS 6399:3: 0.75 kPa.
  • Safety: Non-fragile – Rooflights achieve a Class B rating to ACR[M]001:2014.
  • Thermal performance: U-values below 1.3 W/m²K available.

General information
Specification data - Framed rooflights
Product Reference

Xspan Barrel Vault


Low profile

Forms a low-rise arc, spanning between supporting structures.


A simple semi-circle that either tops the supporting structure or can be extended on vertical legs.

Upstand/ kerb finish

Mill finish

Polyester powder coated

Insert colour requirement.

Glazing -

Solid single skin polycarbonate

For glazed canopies and unheated spaces.

Multi-wall structured polycarbonate





Standard product features

Loading class:

To BS EN 1991-1-1: 2002 and BS EN 1991-1-7: 2006+A1: 2004.

Fire performance (to BS 476, Part 7):

Class 1, AA designation (national classification), or Broof (t4) European classification for spread of flame.

Product Options


- Low profile:

Forms a low-rise arc spanning between supporting structures. The normal geometry of the vault is for the radius to be equal to the span, although other geometries are possible. Consult manufacturer for details.

- Semi-circular:

The vault can sit directly on the supporting structure, or can be extended on vertical legs to accommodate windows, vents or louvres.


Large spans can be achieved, although a substructure for additional support would then be required. Consult manufacturer for details.

Upstand/ kerb finish:

Upstands are available in mill finish or polyester powder coated white as standard (other colours available on request): consult manufacturer for colour range and samples.


– Type:

Available with Lumira technology, consult manufacturer for details.

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