ThermRite 18mm Routed Plain Edge Dry Screed Overlay Boards with Straight Runs

The ThermRite Routed Dry Screed Overlay Boards with Straight Runs (No Turns) are low profile, high strength, grooved cement boards designed to enable tiling directly on top. At just 18mm thick and designed for use with 12mm underfloor heating pipe, these cement boards provide a durable, efficient overlay offering rapid heat transfer and low thermal resistance.

Featuring four grooves at 150mm centres to securely accommodate 12mm pipes, these boards have a plain edge profile requiring joint adhesive for installation. They are suitable for laying directly onto screed or wood subfloors and can be combined with insulation boards underneath to reduce downward heat loss. Their high-density construction offers excellent impact resistance, stability, and durability.

What’s Included

• Boards sized 800mm x 600mm
• Board thickness: 18mm
• Grooves: 4 grooves at 150mm centres for 12mm pipe
• Coverage per board: 0.42 m²
• Installation joint adhesive (sold separately)

Key Features

• Low profile 18mm thickness ideal for minimal floor build-up
• High thermal conductivity (0.40 W/mK) and very low thermal resistance (0.045 m²·K/W)
• Plain edge profile requiring adhesive joint sealing
• Four grooves at 150mm centres for precise pipe positioning and secure fit of 12mm multilayer pipe
• High impact resistance and dimensional stability—does not expand or contract like chipboard when exposed to moisture
• Designed for direct tiling application without screeding
• Can be installed over 6mm or 10mm insulation boards to improve floor heating efficiency
• Quick and easy installation for professional results

Benefits

• Enhances underfloor heating system efficiency with superior thermal transfer
• Reduces room floor build height—ideal for refurbishments or new builds with height restrictions
• Durable and stable surface suitable for ceramic tile and other floor finishes
• Supports rapid heat-up times and improved comfort levels
• Eliminates the need for additional screed layers

Technical Specifications

The ThermRite Routed Dry Screed Overlay Boards with Straight Runs (No Turns) – Plain Edge Profile provide a professional low-profile flooring solution for underfloor heating installations, combining high thermal performance, durability, and a flat surface ready for direct tile finishing.