From £16.60 + VAT per board

Wood fibre insulation sarking board – Beltermo Top

Beltermo Top wood fibre insulation sarking boards are:-

  • a high density, dry-process wood fibre insulation board, brilliant for keeping you warm and dry in winter.
  • great for summer heat shielding, keeping your home cool.
  • ideal for forming a warm roof which is completely vapour permeable.
  • a quick and easy way to form a weather-tight, bat friendly covering without using membranes/felt.

Product overview

Where is it used?

  • On top of your rafters, preventing thermal bridging and keeping noise out, especially for loft conversions.
  • Behind any cladding on walls on timber frames or masonry.
  • Any roofs where bats live. They get tangled in membranes!!

How is it used?

  • The Beltermo Top wood fibre insulation sarking boards should be laid on top of the rafters and fixed in place with counter-battens.
  • For roofing applications the first row should start at eaves level and working in rows, work your way up the roof.
  • To reduce waste the overhang from the first row should be trimmed off and used to start the second row and so on.
  • For use behind cladding the same principles apply. When working on masonry structures, unless the wall is very flat, timber battens should be fixed to the surface first with SteicoFlex flexible wood fibre insulation between the battens. The Beltermo Top can then be fixed to these battens, avoiding any voids behind.
  • Any cut joints or corners can be taped with Ampacoll Fenax tape to ensure weather-tightness.
  • 35mm boards are not suitable for walking directly on unless supported underneath.
  • For installations where the Beltermo Top will be left exposed for more than 4 weeks or where metal roofing is to be used, install Ampatop Protecta breathable membrane over, prior to fixing of the counter-battens.

How much will you need?

  • The 35mm Beltermo Top boards cover an area of 2475 x 575mm (1.423m²).
  • Allow 5-10% wastage depending on the complexity of the roof/facade.

Frequently asked questions

What is their thermal conductivity?

The Beltermo Top boards have a conductivity of 0.044 W/mK, a density of 200 kg/m³ and a compressive strength of 200kPa (kN/m²)

See it in action

Wood fibre sarking boards - Over rafter insulation

Wood fibre sarking boards - Flat roof construction

Pricing & shipping

This product will require three pallet spaces and so shipping is likely to cost between £150 and £300, depending on where you live. Contact Us for a more accurate costing.

Thickness [mm]Weight [kg/sqm]Board dim. [cm], Area [m²]Number of boards per palletPallet covers [sqm]Pallet weight [kg]Pallet dim. [cm] [LxWxH]single board costboard in full pallets
357247.5 x 57.5, 1.4236493.92680120 x 250 x 127£18.44£16.60

Book your free project consultation

We’d like to hear from you. Call us on 01392 861763 or email us at with any questions or comments.

If you can’t seem to find what you need on our website or you have large quantities of materials to purchase please contact us for a chat and we’ll offer you a more bespoke solution.

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