Roof insulation boards are an insulation material designed specifically to be applied to the application of pitched roofs or flat roofs within residential and commercial buildings. The boards are generally made up of a polyisocyanurate (PIR) core with foil or glass tissue facings bonded to each side. Roof insulation boards are 1200mm x 600mm / 2400mm with thicknesses between 25mm and 150mm.

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100mm Recticel GP Insulation Boards (1200x2400mm)

£36.20 ex VAT

Celotex 100mm PIR Insulation Board – GA4100 (2.4m x 1.2m)

£36.20 ex VAT

Kingspan Kooltherm K7 100mm Pitched Roof Board

£296.89 ex VAT

100mm Kingspan Thermaroof TR24 PIR Flat Roof Insulation Board (1200 x 600mm)

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120mm Celotex Insulation Board – XR4120 (2.4m x 1.2m)

£46.50 ex VAT

120mm Kingspan Thermaroof TR24 PIR Flat Roof Insulation Board (1200 x 600mm)

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25mm Recticel GP Insulation Boards (1200x2400mm)

£14.50 ex VAT

50mm Celotex Insulation Board – GA4050 (2.4m x 1.2m)

£20.69 ex VAT

50mm Recticel GP Insulation Boards (1200x2400mm)

£20.69 ex VAT

70mm Recticel GP Insulation Boards (1200x2400mm)

£29.50 ex VAT

75mm Celotex Insulation Board – GA4075 (2.4m x 1.2m)

£30.96 ex VAT

Kingspan K107 50mm Pitched Roof Insulation Board

£311.19 ex VAT

Kingspan Thermapitch TP10 25mm PIR Insulation Board

£20.95 ex VAT

Kingspan Thermapitch TP10 75mm PIR Insulation Board

£40.37 ex VAT

Kingspan Thermaroof TR26 120mm Flat Roof Insulation Board

£159.62 ex VAT

150mm Celotex Insulation Board – XR4150 (2.4m x 1.2m)

£57.25 ex VAT

What are the benefits of roof insulation boards?

  • Roof insulation boards improve the thermal quality of the property. This means a more temperature-controlled environment with cooler summers and warmer winters. Thermal quality means less drafts, less heat escaping the property and a more comfortable living and working space.
  • Heat rises and can escape through the roof of the building if not insulated correctly. The foil facing on the insulation board stops the heat leaving through the roof and reflects the heat back into the building, heating from the top down.
  • Preventing heat and energy escaping through the roof will save you money on your energy bills with less energy needed to heat your property.
  • With less heat escaping, it will have a positive effect on the global warming and climate change, making your property more energy-efficient and sustainable.
  • When installed correctly, roof insulation will have a lifespan for as long as the building itself.
  • Roof insulation materials are usually lightweight and easy to cut, handle, and install.

Flat Roof Installation – Flat roofs are insulated by externally layering insulation materials on top of the roof (providing it is a warm roof). Plywood and vapour check are fixed to the roof and then insulation is applied and tightly butted together and secured using foil tape. Other methods were then follow such as more battens, plywood, vapour check (weatherproof sheet), and drip trims etc. This method means no mess or changes need to be made to your home internally and will be an easier form of application for the property owner.

Pitched roof installation – Insulation boards should be installed internally. Cut to size and installed in between the rafters in the roof. Any joining boards should be tightly butted together, and tape can be applied at the joins. Insulation boards can then be fitted horizontally across the rafters with fixings going through the boards and into the rafters. Plasterboard can then be applied over the insulation boards or insulated plasterboard can be applied for applications when constructing a room-in-the-roof.

Roof insulation boards can be cut by measuring the boards and marking a size guide. A fine-toothed saw can then be used, or the boards can be scored with a sharp knife, snapped over a hard edge, and scored on the other side.

Ensure a building professional is consulted before installing roof insulation. This is to ensure the insulation materials being used are the correct product for the building, this will avoid potential damage.

If there is existing damp or rot within the roof area this should be cleared by a building professional before the insulation is installed. Insulating damp or rotten areas can cause further damage.

Roof Insulation boards are a high-quality board made up of a rigid polyisocyanurate (PIR) core that has a layer of low emissivity foil or glass tissue bonded to each side. It is lightweight and easy to cut, handle, and install. The boards come in a variety and thicknesses and offer thermal conductivities ranging between 0.022W/mK and 0.027W/mK. PIR Insulation Boards are available from brands Recticel, Ballytherm, Kingspan, Mannok, and more.