NBS Source
List your products
Description

Rockwool warm roof systems used to produce a warm roof construction in buildings with pitched roofs in excess of 15°, providing an effective means of insulating the roof space at rafter level and also offers good acoustic performance.

The Overlay and Underlay boards are vapour permeable and should be used in conjunction with a breather membrane on the outer face, thus preventing the need for ventilation of the roof void. They can be installed directly on a timber rafter construction, or the construction may include profiled steel or timber decking.

Overlay boards may be used without Underlay boards, depending on the U-value requirement. However it is preferable not to use Underlay without Overlay, to avoid any potential for condensation on the tops of the rafters.

System consists of high density rigid Rockwool slab overlay and semi-rigid Rockwool slab underlay.

Design:

The Overlay board is very compression resistant; however it is not a structural board suitable for foot traffic, and should not be designed to add to the structural stability of the roof.

Fire performance:

Incombustible to BS 476-4, rated Class 1 surface spread of flame to BS 476-7 and comply with the performance requirements of Class O of the Building Regulations.

Thermal conductivity:

  • Overlay λ: 0.038 W/mK.
  • Underlay λ: 0.034 W/mK.
  • Vapour Resistivity: 7 MNs/g.

General information
Size

Overlay: 1200 x 1000 mm

Underlay: 1000 x 1140 mm

Uniclass 2015
Mineral wool slab insulation (Pr_25_57_06_56)Primary
Specification data - Mineral wool slab insulation
Product Reference

Overlay And Underlay System

Thickness -
Overlay

50 mm

60 mm

70 mm

80 mm

90 mm

100 mm

Underlay

100 mm

125 mm

150 mm

Rebated edges

Not required

Required

Standard product features

Size:

  • Overlay: 1200 x 1000 mm.
  • Underlay: 1000 x 1140 mm.

Similar products from AIM