The High Output Single Room Overlay Underfloor Heating Kit using XPS400 foil-faced overlay boards is designed for installing water underfloor heating over existing solid or timber subfloors in a single room. It is suited to projects where a minimal increase in floor height is required and disruption to the existing structure is to be avoided.

The system is laid out using 150mm pipe centres, providing increased heat output while operating efficiently at lower water temperatures. This makes it compatible with both air source heat pumps (ASHP) and conventional boiler systems.

The XPS400 insulation boards are pre-routed to accept 16mm pipe and feature a foil surface layer to assist with even heat spread across the floor. The fixed pipe spacing removes the need for guesswork during installation and helps deliver consistent performance across the heated area.

This kit is intended for single zone applications, making it suitable for individual rooms such as kitchens, extensions, bathrooms, or open-plan living spaces. It can operate independently or be integrated into a wider underfloor heating system.

The insulation within the overlay boards helps reduce heat loss into the subfloor, ensuring more of the generated heat is directed upwards into the room. This improves overall efficiency and system response.

Each kit includes all required components for installation, including 20mm XPS400 foil-faced overlay boards, 16mm barrier pipe, stainless steel manifold, pump and mixing valve assembly and connection fittings. All components are sized to match the selected floor area.

• Overlay system for installation directly onto existing subfloors
• 150mm pipe spacing for improved output at lower temperatures
• Compatible with air source heat pumps (ASHP) and standard heating systems
• XPS400 routed insulation boards for consistent pipe layout
• Foil surface layer to aid even heat distribution
• Single zone setup for individual room control
• 16mm oxygen barrier pipe for long-term reliability
• System components matched to coverage area
• Compatible with a range of floor finishes with correct build-up

The pipe is installed into the routed channels within the boards at 150mm centres, allowing warm water to circulate evenly across the floor area. The foil layer assists in spreading heat laterally, while the insulation core limits downward heat loss, helping the system reach operating temperature efficiently.

• Single room upgrades over existing concrete or timber floors
• Kitchen and extension projects
• Bathrooms and smaller heating zones
• Retrofit situations where floor removal is not practical

This kit is intended for installations where a low-profile heating system is required without altering the existing floor structure.