Unilin Thin-R XT/PR_UF Underfloor Insulation Boards are high-performance PIR insulation boards designed specifically for insulating ground supported and suspended floors.
The floor in any building is an area of considerable downward heat loss when not properly insulated.
Thin-R XT/PR_UF significantly improves the U-value of both new and existing floors, helping reduce energy loss and improve overall thermal efficiency.
Thin-R XT/PR_UF is lightweight, easy to install and combines high compressive strength with low thermal conductivity, providing a high-performance solution for floor insulation in both domestic and commercial applications.
Manufactured with a rigid PIR core and low emissivity foil facings, these boards deliver excellent thermal performance while maintaining a slim profile—ideal where floor build-up height is limited.
Features:
- High-performance PIR floor insulation
- Suitable for ground supported and suspended floors
- Suitable for new and existing floors
- Suitable for use with underfloor heating
- High compressive strength
- Lightweight and easy to install
- Reduced thermal bridging
- Reduced risk of condensation
- Closed cell structure for high moisture resistance
- Low emissivity foil facings
- Reduced insulation thickness
- Board size: 2.4m x 1.2m (8ft x 4ft)
- Coverage per board: 2.88m²
Technical Information:
- Range: Thin-R
- Material: PIR (Polyisocyanurate)
- Fire Rating: Euroclass F
- Thermal Conductivity: 0.022 W/mK (BS EN 13165)
- Board Dimensions: 2400mm x 1200mm
- Coverage: 2.88m² per sheet
Documentation:
Thermal Resistance (R-Values):
- 20mm – 0.90 m²K/W
- 25mm – 1.10 m²K/W
- 40mm – 1.80 m²K/W
- 50mm – 2.25 m²K/W
- 60mm – 2.73 m²K/W
- 75mm – 3.41 m²K/W
- 100mm – 4.50 m²K/W
- 125mm – 5.65 m²K/W
- 150mm – 6.80 m²K/W
Applications:
- Ground supported concrete floors
- Suspended timber floors
- New build projects
- Renovation and retrofit applications
- Domestic and commercial construction
Benefits of Insulation Boards:
Enhanced Energy Efficiency: Insulation boards reduce heat transfer, helping maintain consistent indoor temperatures and lowering heating demands, which can help reduce energy bills.
Moisture Resistance: The closed cell PIR core helps resist moisture ingress, reducing the risk of condensation and protecting the building structure.
Space Saving: Thanks to excellent thermal performance, thinner boards can often achieve required insulation values while minimising floor build-up.
Improved Comfort: Proper floor insulation helps create warmer floors and a more comfortable internal environment all year round.
Installation Guide:
- Ensure the floor surface is clean, dry, and level before installation.
- Measure the area carefully and cut boards accurately using a fine-toothed saw or sharp knife.
- Lay boards tightly together to minimise gaps and thermal bridging.
- Seal joints where required in accordance with manufacturer recommendations.
- Install floor finishes or screed as specified for your build-up design.
With rising energy costs and increasing focus on building efficiency, Unilin Thin-R XT/PR_UF floor insulation boards provide a reliable, high-performance solution for reducing heat loss through floors while improving comfort and long-term energy savings.