125mm Unilin Thin-R PIR Insulation Board

Unilin Insulation (formerly Xtratherm) Thin-R PIR

125mm Unilin Thin-R Insulation Board (2400mm x 1200mm x 125mm) is a high-performance PIR rigid foil faced polyisocyanurate thermal foam board suitable for multiple applications including roofs, walls, floors, and timber and steel framed construction systems. With a certified thermal conductivity of 0.022 W/mK, this board delivers excellent thermal performance.

About

125mm Unilin PIR is particularly effective for pitched roof applications (ventilated, hybrid or warm roof designs), providing outstanding U-values whilst minimising impact on internal headroom. The roof is a critical building element where significant heat loss occurs. This board reduces thermal loss effectively whilst delivering superior thermal bridging performance. Suitable for various construction methods including pitched roof insulation, wall applications, and floor systems, the product combines lightweight construction with straightforward installation. The board offers fire resistance, water repellence, and minimal environmental impact.

Product Details

Thickness: 125mm

Length: 2400mm

Width: 1200mm

Overall Thickness: 15mm, 20mm, 25mm, 30mm, 35mm, 40mm, 45mm, 50mm, 60mm, 65mm, 70mm, 75mm, 80mm, 90mm, 100mm, 110mm, 120mm, 130mm, 140mm, 150mm, 160mm, 165mm

Maximum board weight: 0.45 kg/m2

Thermal Resistance: 5.45m2K/W

Thermal conductivity: 0.022 W/mK

Compressive strength: >150 kPa

Water Vapour Resistivity: >100 MNs/gm

Density (Foam Core): 30-32 Kg/m3

Surface spread of flame: Class 1

Reaction to fire: E

Finish: Aluminium Foil Facings

Applications: Roofs, Walls, Floors, Timber & Steel Frame

ETA Notification: Yes

Features: Versatile ǀ High-performance ǀ Rigid

Warm roof insulation construction offers an effective solution for complex roof designs. Positioning insulation above or between roof timbers maintains the structural envelope at internal temperatures, reducing thermal stress and condensation issues.

The 125mm PIR insulation must be stored on a clean, flat surface away from ground contact and kept under cover. Polythene wrapping alone does not provide adequate outdoor protection. Protect the boards during storage and construction phases. The insulation boards can be cut easily with a sharp knife or fine-toothed saw.

Key Facts

1. Unilin 125mm PIR achieves an A+ rating under the BRE Green Guide.
2. Certified Lambda value of 0.022 W/mK.
3. Minimises intrusion into living space.
4. Reduces condensation risk.
5. Low emissivity foil facings.
6. Lightweight and simple to install.
7. Minimises thermal bridging.
8. Suitable for ventilated roof designs.
9. Suitable for warm roof designs.
10. Suitable for hybrid roof designs.

Browse our Unilin range and filter by thickness or coverage on the left-hand side. For project suitability advice or bulk pricing enquiries, contact us on +4402038839057, email sales@insulationbee, or use Live Chat - Competitive UK Insulation Pricing.