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Roofbox K6
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Can be used where an upstand is required around a roof opening, including rooflights, lantern lights and roof hatches, and corresponding Roofbox M roof cabinets.


Insulated kerb upstand to suit roof opening 1500 x 4500 mm, compatible with Roofbox M6 modular roof cabinets.

Features and benefits:

  • Modular kerb upstand system, manufactured off-site for fast installation.
  • Enables upstand installation as soon as the roof opening is formed, assisting the early weathering of openings.
  • Can be supplied either as pre-assembled or individual parts ready to bolt together, to, "bolt together suit the particular handling requirements.
  • Internally insulated system means that upstand thickness is reduced; beneficial when space is at a premium.
  • Pre-insulated aluminium construction and thermal break element provide increased thermal efficiency.
  • No requirement for on-site formwork and other labour involved in producing site-made kerb upstands, offering potential savings compared to over cast concrete kerbs.
  • Available in heights up to 600 mm to suit various roof build-up thicknesses.
  • Bespoke configurations are available (specified separately).

General information








2.0 mm-thick, 5251 grade.

Polyisocyanurate (PIR)





4730 mm


1730 mm


200 mm

375 mm

450 mm

600 mm


Pr_80_77_28_74 Roof penetration boxesPrimary
Pr_30_59_36_11 Carbon steel access hatches
Pr_30_59_36_80 Stainless steel access hatches
Pr_30_59_36_02 Aluminium access hatches
Pr_30_59_72_31 Framed rooflights


J31/130 Inverted roof coating

J41/135 Single-layer reinforced bitumen membrane cold deck roof covering

L10/460 Rooflights

L20/630 Hatches

J31/5 Cold deck roof coating

J31/12 Inverted roof coating

J41/12 Reinforced bitumen membrane cold deck roof covering

J31/110 Cold deck roof coating

J41/130 Built-up reinforced bitumen membrane cold deck roof covering

J41/120 Built-up reinforced bitumen membrane inverted roof covering

J41/125 Single-layer reinforced bitumen membrane inverted roof covering

Q37/120 Simple intensive green roof

Q37/130 Extensive green roof

Q37/110 Intensive green roof

L10/45 Rooflights

Specification data - Roof penetration boxes Enhanced data


2 mm-thick 5251 grade aluminium.

  • Section bolting: A2 stainless steel M10 bolts, nuts and washers.
  • Thermal break: 5 x 25 mm HDPE strip.


Further insulation options are available to provide enhanced U-values and fire ratings. Consult manufacturer for details.

100 mm-thick foil faced polyisocyanurate (PIR).

U-value: 0.022 W/m·K.

Factory finish



Polyester powder-coated.


RAL 7047.


RAL, bespoke.

Insert requirement.

Film thickness (minimum)

Manufacturer's standard.



Roof opening

1500 x 4500 mm.

Integral kerb

200 mm high.

Width: 115 mm.

Fixing flange: 50 mm.

Maximum live load

5.0 kN/m.

Fire performance

Class 1 (BS 476, Part 7); Euroclass F (BS EN 13501-1).


Why use the ROOFBOX system?

Why use the ROOFBOX system?

ROOFBOX Standard and modular roof cabinets

ROOFBOX Standard and modular roof cabinets

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