Floor Insulation

Buy floor insulation from Insulation UK, your specialist supplier of floor insulation products for concrete floors, suspended timber floors, and underfloor heating applications. We stock a comprehensive range including PIR insulation boards from Celotex, Kingspan and Recticel, EPS insulation from Jablite and Sundolitt, XPS insulation boards, and mineral wool slabs from Rockwool and Knauf. Available in thicknesses from 20mm to 300mm to achieve U-values of 0.15-0.25 W/m²K for Building Regulations compliance.
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Floor Insulation Types & Applications

Choosing the right floor insulation depends on your floor type, application, and performance requirements. At Insulation UK, we stock all major floor insulation materials to suit every project.

PIR Insulation Boards for Floors

PIR (polyisocyanurate) insulation boards offer the best thermal performance at just 0.022 W/mK thermal conductivity. These rigid boards are ideal for both concrete and suspended floors where space is limited and maximum insulation is required. Popular choices include Celotex GA4000 and XR4000 ranges, Kingspan TF70 ThermaFloor, and Recticel Eurothane GP boards. PIR boards are lightweight, easy to cut, and achieve excellent U-values in thinner profiles compared to other insulation types. Available in thicknesses from 25mm to 200mm.

EPS Floor Insulation

Expanded polystyrene (EPS) insulation provides a cost-effective solution for concrete floor insulation. Jablite Jabfloor is available in multiple compressive strength grades from EPS70 (70 kPa) to EPS500 (500 kPa), making it suitable for domestic, commercial, and industrial floor applications. EPS insulation is particularly popular for ground floors over hardcore, offering excellent load-bearing capacity at competitive prices. Choose higher grades (EPS200-500) for heavy-duty applications like warehouses or areas with vehicular traffic.

XPS Insulation Boards

Extruded polystyrene (XPS) boards provide superior moisture resistance and high compressive strength, making them the ideal choice for below ground-level applications, basements, and areas prone to dampness. Kingspan GreenGuard and Ravatherm XPS ranges offer compressive strengths from 300-700 kPa with excellent long-term performance even in wet conditions. XPS is perfect for inverted roof applications and perimeter insulation where moisture exposure is a concern.

Mineral Wool for Suspended Floors

Flexible mineral wool slabs fit snugly between floor joists in suspended timber floors. Rockwool RWA45 and Knauf Acoustic Roll provide both thermal insulation (0.034-0.035 W/mK) and excellent acoustic performance to reduce impact noise between floors. These semi-rigid slabs are friction-fit between joists, eliminating the need for additional fixings. Available in thicknesses from 50mm to 200mm to suit different joist depths.

 

Shop Floor Insulation by Application

Concrete Floor Insulation Insulating solid concrete floors over hardcore or existing slabs. Best options: PIR boards, EPS boards (EPS100-200), or XPS boards. Typical build-up: DPM → insulation → screed → floor finish.

Suspended Floor Insulation
Between-joist insulation for timber suspended floors. Best options: PIR insulation strips cut to joist width (400mm or 600mm), or mineral wool slabs. Install netting beneath joists to support insulation.

Underfloor Heating Insulation Maximize UFH efficiency with high-density insulation beneath heating pipes. Best options: high-compressive-strength PIR boards or specialist UFH boards. Achieves faster heat-up times and lower running costs.

Acoustic Floor Insulation Reduce impact noise and airborne sound transmission between floors. Best options: High-density mineral wool slabs (Rockwool RWA45, Knauf Acoustic Roll) or specialist acoustic underlays combined with insulation boards.

 

Why Choose Insulation UK for Floor Insulation?

Comprehensive Range

PIR, EPS, XPS, mineral wool and specialist products all in stock

Top Brands

Celotex, Kingspan, Jablite, Rockwool, Knauf, Ravatherm and more

Competitive Prices

Low trade prices on all floor insulation products

Expert Advice

Technical support to help you choose the right product

Fast Delivery

UK-wide delivery with free shipping on orders over £500 (ex VAT)

Multiple Thicknesses

25mm to 300mm to achieve required U-values

Compliance 

All products suitable for achieving 0.15-0.25 W/m²K U-values