Where to buy PIR insulation?

You can buy PIR board insulation online from specialist insulation stores such as Insulation Wholesale. As a leading PIR insulation supplier, we stock a full range of panels for walls, floors, roofs, and lofts – from foil-faced wall panels to roof-ready boards and heavy-duty floor insulation. If you are budgeting for a project, our team can provide quick, accurate quotes so you know the current PIR insulation prices before you order.

How to cut PIR insulation?

Mark your cut line. Use a straightedge or long level. If your line is crooked, your cut will be too. Score the foil first. Take a sharp utility knife and lightly score along your line. This does not slice the board – it just breaks the foil, leaving a neat edge. Deepen the cut. Run your knife over the same line three or four times. You will feel it sink deeper each pass. For thinner boards (25–50mm), you can usually cut through the material with the knife alone. Snap the board. For thicker boards (75–150mm), once the knife has cut through the foil and a bit into the foam, tilt the board over an edge or your knee and snap it along the scored part. The core breaks cleanly. Trim the back. After snapping, the face will be clean-cut, and the back partially torn. Score the back foil with your knife and slice off the remaining foam. Optional: use a handsaw. If you prefer one tool start to finish, a fine-tooth handsaw works well. It is slightly messier but great for deep cuts or angled pieces.

How to install PIR insulation?

1.Between Studs, Joists, or Rafters This is the classic “cut to fit and friction-fix” method. Cut each board 3–5 mm wider than the gap. Fit it into the space so it grips the sides. That slight pressure keeps it snug. Make sure the face of the board sits flush with the timber so your plasterboard or internal lining lands cleanly. Tape the foil joints to get a tighter vapour barrier. PIR is rigid enough to bridge the gap, and the foil face helps stop air movement. Always follow system-specific guidance for vapour control and ventilation requirements. 2.Over Joists, Rafters, or Stud Walls (Continuous Layer) This provides the best thermal performance by eliminating cold spots. Fix the boards directly over the timber using insulation fixings or long screws with washers. Stagger the joints so no straight lines run through the insulation. Tape all joints with foil tape to seal the layer. Fit your plasterboard or deck on top using long screws that reach the timber below. The full sheet covers every timber, giving a more even thermal layer. 3.Solid Masonry Walls (Internal Facing) This is the "insulated lining board" approach. Dot-and-dab adhesive or mechanical fixings can be used, depending on the spec. Boards must sit flat with no steps between them. Tape joints, then add plasterboard over the top, or use insulated plasterboard that includes PIR. It creates a warm internal surface and stops heat from bleeding into the cold wall. 4.Floors Most PIR in floors is installed under the screed or under a chipboard deck. Lay a DPM if needed. Put PIR boards tightly together with staggered joints. Tape where required, then add your screed or deck on top. The rigid foam handles the load once it is supported by the layers above. 5.Flat Roofs Both warm-roof and inverted-roof setups commonly use PIR. Lay the boards over the roof deck. Stagger joints. Mechanically fix or bond, depending on the roof system. Add the waterproofing membrane over the top.

Can PIR insulation get wet?

PIR itself does not soak up water easily. So if the board gets a light splash or short-term exposure, it will not suddenly fall apart or lose its thermal performance. But it is not designed to stay wet because this can affect long-term stability. Long-term immersion or condensation behind the board can degrade facers or structure.

Can you use PIR insulation in loft?

Yes, PIR insulation works very well in a loft. Between Rafters Fit PIR panels snugly between the rafters, leaving the required ventilation gap above – usually 25–50mm, depending on the roof. Seal small gaps with foam or tape to prevent cold bridges. Under Rafters (to boost U-value) A continuous layer of foil-faced PIR is fixed across the underside of the rafters. This adds thermal performance, covers up imperfect cuts between rafters, and the foil layer acts as a vapour-control layer once joints are taped. Over Rafters (warm roof method) If you are re-roofing, PIR slabs can be laid on top of the rafters before the breather membrane and tiles go on. This gives you a full warm roof with minimal thermal bridging – the most efficient loft system, but only practical during roof replacement.

PIR Polyisocyanurate Insulation At Low Wholesale Prices

25mm Recticel Eurothane GP PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

25mm Recticel Eurothane GP is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Recticel is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£11.76£14.11 Ex VATInc VAT
£4.08£4.90 Per M2 Add to cart

25mm Recticel Powerdeck F Flat Roof Insulation Board 1200mm x 600mm Pack of 20 (14.40m2)

Recticel-Powerdeck-F-Insulation-Board-Zoomed

Recticel-Powerdeck-F-Insulation-Board-Application-Cutting

Recticel-Powerdeck-F-Insulation-Board-Application

25mm Recticel Powerdeck F Flat Roof Insulation Board 1200mm x 600mm Pack of 20 (14.40m2)

25mm Powerdeck F flat roof insulation board is compatible with multiple waterproofing systems, benefiting from high compressive strength and excellent dimensional stability. Both sides of Powerdeck F are faced with a mineral coated glass fleece.

£120.00£144.00 Ex VATInc VAT
£8.33£10.00 Per M2 Add to cart

30mm Celotex TB4030 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

Celotex-PIR-Insulation-Board-Floor2-Application

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30mm Celotex TB4030 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

30mm Celotex TB4030 is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Celotex is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£15.21£18.25 Ex VATInc VAT
£5.28£6.34 Per M2 Add to cart

30mm Ecotherm Eco-Versal PIR Insulation Board 2400mm x 1200mm (8' x 4') 2.88m2

Ecotherm-Eco-Versal-Insulation-Board-Pitched-Roof-Application

Ecotherm-Eco-Versal-Insulation-Board-Floor-Application

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30mm Ecotherm Eco-Versal PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

30mm Ecotherm Eco-Versal is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Ecotherm Eco-Versal is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£14.13£16.96 Ex VATInc VAT
£4.91£5.89 Per M2 Add to cart

30mm Kingspan Therma TP10 / TF70 / TW55 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) Pack of 10 (28.8m2)

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30mm Kingspan Therma TP10 / TF70 / TW55 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) Pack of 10 (28.8m2)

All three models 30mm Kingspan Therma PIR Insulation Board:

30mm Thermapitch TP10
30mm Thermafloor TF70
30mm Thermawall TW55

share the same high-performance PIR core and low-emissivity foil facings, offering excellent thermal efficiency and easy installation. Although labeled differently, these boards share identical technical specifications.

£214.32£257.18 Ex VATInc VAT
£7.44£8.93 Per M2 Add to cart

30mm Recticel Eurothane GP PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

30mm Recticel Eurothane GP is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Recticel is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£14.20£17.04 Ex VATInc VAT
£4.93£5.92 Per M2 Add to cart

40mm Celotex PIR Insulated Plasterboard 1200mm x 2400mm + 12.5mm P/B 2.88m2

Celotex-Insulated-Plasterboard-PL-Wall-Application

40mm Celotex PIR Insulated Plasterboard 1200mm x 2400mm + 12.5mm P/B 2.88m2

40mm Celotex PL4040 PIR Insulated Plasterboard is it is suitable for use in roof and internal wall lining applications. Celotex Insulated Plasterboard is a high performance, easy to install PIR insulation board with a paper facing, laminated to a piece of 12.5mm tapered edge plasterboard.

£37.68£45.22 Ex VATInc VAT
£13.08£15.70 Per M2 Add to cart

40mm Celotex TB4040 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

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40mm Celotex TB4040 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

40mm Celotex TB4040 is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Celotex is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£18.48£22.18 Ex VATInc VAT
£6.42£7.70 Per M2 Add to cart

40mm Ecotherm Eco-Versal PIR Insulation Board 2400mm x 1200mm (8' x 4') 2.88m2

40mm Ecotherm Eco-Versal PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

40mm Ecotherm Eco-Versal is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Ecotherm Eco-Versal is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£16.23£19.48 Ex VATInc VAT
£5.64£6.77 Per M2 Add to cart

40mm Kingspan Therma TP10 / TF70 / TW55 PIR Insulation Board 2400mm x 1200mm (8' x 4') Pack of 8 (23.04m2)

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40mm Kingspan Therma TP10 / TF70 / TW55 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) Pack of 8 (23.04m2)

All three models 40mm Kingspan Therma PIR Insulation Board:

40mm Thermapitch TP10
40mm Thermafloor TF70
40mm Thermawall TW55

share the same high-performance PIR core and low-emissivity foil facings, offering excellent thermal efficiency and easy installation. Although labeled differently, these boards share identical technical specifications.

Non-refundable.

£195.45£234.54 Ex VATInc VAT
£8.48£10.18 Per M2 Add to cart

40mm Kingspan Thermawall TW50 PIR Insulation Board 1200mm x 450mm Pack of 12 (6.48m2)

Kingspan-Thermawall-TW50-Cavity-Wall-PIR-Insulation-Board-Application2

Kingspan-Thermawall-TW50-Cavity-Wall-PIR-Insulation-Board-Application

40mm Kingspan Thermawall TW50 PIR Insulation Board 1200mm x 450mm Pack of 12 (6.48m2)

40mm Kingspan Thermawall TW50 is a high performance insulation with thermal conductivity of 0.022 W/mK. Therma is a range of PIR insulation available in a range of thicknesses.

£65.72£78.86 Ex VATInc VAT
£10.14£12.17 Per M2 Add to cart

40mm Recticel Eurothane GP PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

40mm Recticel Eurothane GP is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Recticel is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£16.61£19.93 Ex VATInc VAT
£5.77£6.92 Per M2 Add to cart

50mm Celotex CW4050 Cavity Wall Insulation Board 1200mm x 450mm 5.94m2 Pack of 11 (5.94m2)

Celotex-Partial-Fill-Caivty-Board-Pack-of-10

50mm Celotex CW4050 Cavity Wall Insulation Board 1200mm x 450mm 5.94m2 Pack of 11 (5.94m2)

50mm Celotex CW4050 Cavity Wall Insulation Board is an easy to install polyisocyanurate (PIR) insulation board with excellent thermal performance, featuring a low emissivity foil facing.

£51.61£61.93 Ex VATInc VAT
£8.69£10.43 Per M2 Add to cart

50mm Celotex GA4050 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

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50mm Celotex GA4050 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

50mm Celotex GA4050 is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Celotex is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£19.37£23.24 Ex VATInc VAT
£6.73£8.08 Per M2 Add to cart

50mm Celotex PIR Insulated Plasterboard 1200mm x 2400mm + 12.5mm P/B 2.88m2

50mm Celotex PIR Insulated Plasterboard 1200mm x 2400mm + 12.5mm P/B 2.88m2

50mm + 12.5mm Celotex PL4050 PIR Insulated Plasterboard is it is suitable for use in roof and internal wall lining applications. Celotex Insulated Plasterboard is a high performance, easy to install PIR insulation board with a paper facing, laminated to a piece of 12.5mm tapered edge plasterboard.

£40.37£48.44 Ex VATInc VAT
£14.02£16.82 Per M2 Add to cart

50mm Ecotherm Eco-Versal PIR Insulation Board 2400mm x 1200mm (8' x 4') 2.88m2

50mm Ecotherm Eco-Versal PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

50mm Ecotherm Eco-Versal is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Ecotherm Eco-Versal is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£17.50£21.00 Ex VATInc VAT
£6.08£7.30 Per M2 Add to cart

50mm Kingspan Therma TP10 / TF70 / TW55 PIR Insulation Board 154.836m (8' x 4') Pack of 6 (17.28m2)

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50mm Kingspan Therma TP10 / TF70 / TW55 PIR Insulation Board 154.836m (8′ x 4′) Pack of 6 (17.28m2)

All three models 50mm Kingspan Therma PIR Insulation Board:

50mm Thermapitch TP10
50mm Thermafloor TF70
50mm Thermawall TW55

share the same high-performance PIR core and low-emissivity foil facings, offering excellent thermal efficiency and easy installation. Although labeled differently, these boards share identical technical specifications.

£162.95£195.54 Ex VATInc VAT
£9.43£11.32 Per M2 Add to cart

50mm Kingspan Thermaroof TR24 Flat Roof PIR Insulation Board 1200mm x 600mm Pack of 6 (4.32m2)

Thermaroof TR24-Flat-Roof-PIR-Insulation-Board-Zoom-Out

Thermaroof TR24-Flat-Roof-PIR-Insulation-Board-Application-2

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50mm Kingspan Thermaroof TR24 Flat Roof PIR Insulation Board 1200mm x 600mm Pack of 6 (4.32m2)

50mm Kingspan Thermaroof TR24 is a high performance insulation with a fibre-free rigid thermoset polyisocyanurate (PIR) core. Kingspan Thermaroof is suitable for flat roofs waterproofed with partially bonded torch applied multi-layer bituminous waterproofing.

£64.73£77.68 Ex VATInc VAT
£14.98£17.98 Per M2 Add to cart

50mm Kingspan Thermaroof TR26 PIR Insulation Board 2400mm x 1200mm (8' x 4') Pack of 6 (17.28m2)

Kingspan-Thermaroof-TR26-Insulation-Board

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50mm Kingspan Thermaroof TR26 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) Pack of 6 (17.28m2)

50mm Kingspan TR26 Thermaroof is high-performance insulation that has a fiber-free rigid thermoset polyisocyanurate (PIR) core. Suitable for flat roof application waterproofed with mechanically fixed single-ply waterproofing.

£222.89£267.47 Ex VATInc VAT
£12.90£15.48 Per M2 Add to cart

50mm Kingspan Thermaroof TR27 PIR Insulation Board 1200mm x 1200mm Pack of 6 (8.64m2)

Kingspan-Thermaroof-TR27-Insulation-Board

Kingspan-Thermaroof-TR27-Insulation-Board-Application

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50mm Kingspan Thermaroof TR27 PIR Insulation Board 1200mm x 1200mm Pack of 6 (8.64m2)

50mm Kingspan Thermaroof TR27 is a high performance insulation with a fibre-free rigid thermoset polyisocyanurate (PIR) core. It is used to insulate flat roofs waterproofed with fully adhered single-ply, partially bonded built-up felt, mastic asphalt and cold liquid applied waterproofing.

Non-refundable.

£119.66£143.59 Ex VATInc VAT
£13.85£16.62 Per M2 Add to cart

50mm Kingspan Thermawall TW50 PIR Insulation Board 1200mm x 450mm Pack of 10 (5.40m2)

50mm Kingspan Thermawall TW50 PIR Insulation Board 1200mm x 450mm Pack of 10 (5.40m2)

50mm Kingspan Thermawall TW50 is a high performance insulation with thermal conductivity of 0.022 W/mK. Therma is a range of PIR insulation available in a range of thicknesses.

Non-refundable.

£56.93£68.32 Ex VATInc VAT
£10.54£12.65 Per M2 Add to cart

50mm Recticel Eurothane GP PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

50mm Recticel Eurothane GP is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Recticel is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£18.13£21.76 Ex VATInc VAT
£6.30£7.56 Per M2 Add to cart

50mm Recticel Eurowall Partial Cavity Wall Insulation Board 1200mm x 450mm Pack of 20 (10.80m2)

Recticel-Partial-Cavity-Fill-Square-Edge

50mm Recticel Eurowall Partial Cavity Wall Insulation Board 1200mm x 450mm Pack of 20 (10.80m2)

50mm Recticel Eurowall Partial Cavity is an advanced thermal insulation panel tailored for use in cavity wall systems, delivering exceptional energy efficiency and robust performance.

£107.34£128.81 Ex VATInc VAT
£9.94£11.93 Per M2 Add to cart

50mm Recticel Powerdeck F Flat Roof Insulation Board 1200mm x 600mm Pack of 10 (7.20m2)

50mm Recticel Powerdeck F Flat Roof Insulation Board 1200mm x 600mm Pack of 10 (7.20m2)

50mm Powerdeck F flat roof insulation board is compatible with multiple waterproofing systems, benefiting from high compressive strength and excellent dimensional stability. Both sides of Powerdeck F are faced with a mineral coated glass fleece.

£84.21£101.05 Ex VATInc VAT
£11.70£14.04 Per M2 Add to cart

50mm Recticel Powerdeck U Flat Roof Insulation Board 1200mm x 600mm Pack of 10 (7.20m2)

Recticel-Powerdeck-U-Flat-Roof-Insulation-Board

Recticel-Powerdeck-U-Flat-Roof-Insulation-Board-Application

50mm Recticel Powerdeck U Flat Roof Insulation Board 1200mm x 600mm Pack of 10 (7.20m2)

50mm Powerdeck U flat roof insulation board is a high performance rigid PIR insulation board for use in warm flat roofs with bituminous torch-on felt waterproofing systems. Both sides of Powerdeck U are faced with a bituminous coated glass fleece.

£89.47£107.36 Ex VATInc VAT
£12.43£14.92 Per M2 Add to cart

60mm Celotex CW4060 Cavity Wall Insulation Board 1200mm x 450mm 5.4m2 Pack of 10

60mm Celotex CW4060 Cavity Wall Insulation Board 1200mm x 450mm 5.4m2 Pack of 10

60mm Celotex CW4060 Cavity Wall Insulation Board is an easy to install polyisocyanurate (PIR) insulation board with excellent thermal performance, featuring a low emissivity foil facing.

£54.22£65.06 Ex VATInc VAT
£10.04£12.05 Per M2 Add to cart

60mm Celotex GA4060 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

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60mm Celotex GA4060 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

60mm Celotex GA4060 is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Celotex is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£24.93£29.92 Ex VATInc VAT
£8.66£10.39 Per M2 Add to cart

60mm Celotex PIR Insulated Plasterboard 1200mm x 2400mm + 12.5mm P/B 2.88m2

60mm Celotex PIR Insulated Plasterboard 1200mm x 2400mm + 12.5mm P/B 2.88m2

60mm + 12.5mm Celotex PL4060 PIR Insulated Plasterboard is it is suitable for use in roof and internal wall lining applications. Celotex Insulated Plasterboard is a high performance, easy to install PIR insulation board with a paper facing, laminated to a piece of 12.5mm tapered edge plasterboard.

£42.13£50.56 Ex VATInc VAT
£14.63£17.56 Per M2 Add to cart

60mm Ecotherm Eco-Versal PIR Insulation Board 2400mm x 1200mm (8' x 4') 2.88m2

60mm Ecotherm Eco-Versal PIR Insulation Board 2400mm x 1200mm (8′ x 4′) 2.88m2

60mm Ecotherm Eco-Versal is a polyisocyanurate (PIR) insulation core with composite aluminium foil facings on both sides. Ecotherm Eco-Versal is a multi-purpose insulation board suitable for use in pitched roofs, ceilings, floors and walls.

£22.35£26.82 Ex VATInc VAT
£7.76£9.31 Per M2 Add to cart

60mm Kingspan Therma TP10 / TF70 / TW55 PIR Insulation Board 2400mm x 1200mm (8' x 4') Pack of 5 (14.40m2)

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60mm Kingspan Therma TP10 / TF70 / TW55 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) Pack of 5 (14.40m2)

All three models 60mm Kingspan Therma PIR Insulation Board:

60mm Thermapitch TP10
60mm Thermafloor TF70
60mm Thermawall TW55

share the same high-performance PIR core and low-emissivity foil facings, offering excellent thermal efficiency and easy installation. Although labeled differently, these boards share identical technical specifications.

£168.47£202.16 Ex VATInc VAT
£11.70£14.04 Per M2 Add to cart

60mm Kingspan Thermaroof TR26 PIR Insulation Board 2400mm x 1200mm (8' x 4') Pack of 5 (14.40m2)

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60mm Kingspan Thermaroof TR26 PIR Insulation Board 2400mm x 1200mm (8′ x 4′) Pack of 5 (14.40m2)

60mm Kingspan TR26 Thermaroof is high-performance insulation that has a fiber-free rigid thermoset polyisocyanurate (PIR) core. Suitable for flat roof application waterproofed with mechanically fixed single-ply waterproofing.

£214.19£257.03 Ex VATInc VAT
£14.87£17.84 M2 Add to cart

60mm Kingspan Thermaroof TR27 PIR Insulation Board 1200mm x 1200mm Pack of 5 (7.20m2)

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60mm Kingspan Thermaroof TR27 PIR Insulation Board 1200mm x 1200mm Pack of 5 (7.20m2)

60mm Kingspan Thermaroof TR27 is a high performance insulation with a fibre-free rigid thermoset polyisocyanurate (PIR) core. It is used to insulate flat roofs waterproofed with fully adhered single-ply, partially bonded built-up felt, mastic asphalt and cold liquid applied waterproofing.

£116.51£139.81 Ex VATInc VAT
£16.18£19.42 Per M2 Add to cart