How Water Underfloor Heating Works

Water underfloor heating (UFH) is one of the most comfortable and efficient ways to heat your home. Instead of relying on radiators that heat the air unevenly, it uses a network of warm water pipes hidden beneath your floor to create an even, radiant warmth from the ground up.

Here’s how it works — and why it’s such a smart heating choice.

The Basics

Warm water is circulated through flexible pipes that sit just beneath your floor finish. These pipes connect to a manifold, which distributes the flow of water evenly across the system. The water itself is heated by your chosen heat source — this could be a traditional gas boiler, an air source heat pump, or even a renewable energy system.

As the pipes warm up, they gently heat the floor surface above. That warmth radiates evenly through the room, creating a comfortable temperature from top to bottom — no cold spots, no drafts, and no dry air.

Key Components

• Pipes: Usually made from strong, flexible PEX or multilayer materials that carry heated water safely under your floor.

• Manifold: The central hub that controls the flow and temperature of water going to each heating loop.

• Pump and Mixing Valve: These ensure the right amount of water circulates and that the temperature stays consistent.

• Thermostat: Lets you control the temperature in each room or zone individually.

The Science Behind the Comfort

Underfloor heating uses radiant heat, which warms people and objects directly rather than just heating the air. Because the system runs at lower temperatures than radiators (typically between 35°C–45°C), it’s far more energy-efficient. This means lower running costs and compatibility with renewable heating systems.

Installation Types

• Screed Systems: Pipes are laid within a screed layer — ideal for new builds or major renovations.

• Overlay Systems: Perfect for retrofit projects, where you can install boards with grooves for the pipework directly over existing floors without digging up the subfloor.

Why Choose Water Underfloor Heating

• Even, comfortable warmth throughout the room

• Works efficiently with renewable energy systems

• Hidden from view — no radiators taking up wall space

• Low running costs and reduced energy bills

• Zoned control for individual rooms

• Long lifespan with virtually no maintenance

In Short

Water underfloor heating turns your entire floor into a gentle heat source that keeps rooms consistently warm and comfortable. It’s efficient, invisible, and works beautifully in modern homes, retrofits, and new builds alike.

Explore our full range of Water Underfloor Heating Systems to find the right setup for your project or get in touch for expert advice on designing your system.

ASTECtherm — efficient heating, built in.