Water based underfloor heating runs off your boiler or heat pump and warms the whole floor. It is the usual choice for rooms, extensions, renovations and whole houses. We fit it in three main ways: in screed, as an overlay system over an existing floor, or between the joists of a timber floor.
A continuous loop of pipe is laid across the floor in a set pattern and connected to a manifold, which blends and controls the flow to each circuit. Warm water from your heat source moves through the pipe and the whole floor becomes a gentle, even radiator. Because the surface area is so large, the water does not need to be very hot, which is part of why wet underfloor heating suits both modern boilers and heat pumps.
How the pipework is fitted depends on the floor. That is why there are three main methods, set out below. We do not have a favourite. The right one depends on your property, the floor construction and the project.
The same water based system can be built into the floor in three main ways. Which one is appropriate depends on the property, the floor construction and the project, so we look at each job before advising.
The pipework is installed before screed or concrete is laid over the system.
A low profile panel system is installed over an existing suitable floor, with the final floor finish installed above it.
The underfloor heating system is installed between timber floor joists.
In screed means the pipework is installed before screed or concrete is laid over the system. The pipe sits on insulation and is covered by a screed, either a sand and cement screed or a flowing liquid screed, which holds the heat and spreads it evenly. This is the typical build up for new builds, extensions and any floor being dug out and rebuilt.
It gives an excellent, even heat and works well across large areas. It does add floor height, and the screed needs time to cure before the finished floor goes down, so it needs planning into the programme. We work with your builder and screeder so the pipework is fitted and pressure tested before the screed goes on.
Overlay underfloor heating is a low profile panel system installed over an existing suitable floor. Grooved insulation panels are laid over the floor and the pipe is pressed into the channels, then the final floor finish is installed above it. There is no deep screed, so the floor only rises a small amount, often little enough to keep door heights and thresholds workable in a renovation.
Low profile overlay underfloor heating is the practical choice when you want underfloor heating in a room, or a whole floor, without excavating. Whether it suits your project depends on the existing floor and what else is being done, so it is a good thing to look at on a site visit.
Between joists means the underfloor heating system is installed between timber floor joists. It suits properties with timber floors where the boards can come up. Insulation goes in first so the heat is directed up into the room, the pipework is laid and pressure tested, and the floorboards are then refitted over the top.
It suits homes where the floor level needs to stay as it is, and where the floorboards are coming up anyway as part of the work. Whether it is the right approach depends on how the floor is built, so we look at the floor before advising.
Once the pipework is in, we connect the manifold and set up the controls so that rooms or zones can be managed to suit how you use the space. When the floor is down we set the system up and show you how to use it.
The detail, such as how the design is documented, how many zones are needed and what happens at commissioning and handover, depends on the project. Talk to us about the requirements of yours.
A full width wet underfloor heating circuit laid across a large lower level room. Foil faced insulation lines the walls, the floor is built up over insulation and a membrane, and continuous pipe has been clipped in a tight even pattern with edge insulation around the perimeter, set out and ready for the screed.
A low profile overlay wet system running through a glazed garden room and into the adjoining space. Grooved insulation panels are laid over the existing floor and the pipe is pressed into the routed channels, so the finished floor level barely changes. A good approach where digging out for a deep screed is not practical.
A wet in screed underfloor heating installation in a modern extension with full height sliding glazing onto the garden. Continuous pipe is clipped over insulation in a close even pattern across the whole floor, with blue edge insulation around the perimeter, laid ready for the screed.
A wet underfloor heating circuit in a ground floor extension still under construction. Blockwork walls are up to damp proof course, the floor is built up over insulation and a membrane, and pipe is clipped in a wide even pattern with the layout marked out on site, set out ready for screed.
A wet underfloor heating circuit run across several rooms at first fix stage. Timber stud partitions and blockwork are up, first fix plumbing is in, the floor is built up over insulation and membrane, and continuous pipe is laid in flowing loops from room to room, ready for screed.
A low profile overlay wet system fitted through the hallway and rooms of an existing, already plastered house. Grooved foil faced panels sit on the existing floor and small bore pipe is pressed into the channels, carrying the circuit through doorways from room to room with very little change in floor height.
This wet underfloor heating system was installed between timber joists across several connected areas of an existing property. The photographs show the pipework fitted neatly within the timber floor structure before the final floor finish was installed.
It depends on the space and how it is being built. Wet systems are the usual choice for whole rooms, extensions, renovations and new builds. They run off your boiler or heat pump and are efficient to run over large areas. Electric systems suit smaller areas, single rooms and some situations where build up height is very tight. Tell us about your project and we will talk you through the options.
These are the three main ways a wet system is fitted. In screed means the pipework is installed before screed or concrete is laid over it, which suits new floors, extensions and any floor being dug out and rebuilt. Overlay means a low profile panel system is installed over an existing suitable floor, with the final floor finish installed above it. Between joists means the system is installed between timber floor joists. The right method depends on the property, the floor construction and the project, so we look at each one before advising.
Overlay underfloor heating, sometimes called low profile overlay underfloor heating, is a wet system built from shallow panels laid over an existing suitable floor. The pipe sits in the panels and the final floor finish is installed above it. Because there is no deep screed, it adds much less height than an in screed system, so it is often chosen for renovations and for heating one or two rooms. Whether it suits your project depends on the existing floor, so it is a good thing to look at on a site visit.
In screed systems add the depth of the insulation and the screed, so they suit floors that are being built or dug out. Overlay systems add much less, between joists systems sit within the depth of the floor, and electric mats add very little. The exact height depends on the system chosen, so tell us the floor levels and door heights you are working with.
Wet systems connect to a manifold that feeds each circuit, and the controls are set up so that rooms or zones can be managed to suit how you use them. Electric systems use a thermostat for each heated area. We set up the controls and show you how to use them.
A wet system uses continuous loops of pipe laid over insulation and connected to a manifold with controls. The heat comes from your boiler or heat pump. The pipework is covered by screed or by the floor finish, depending on the system.
Often, yes. Pipework can be laid between the joists with insulation below and the floorboards refitted on top, or an overlay system can go over the boards. Which suits best depends on the floor construction, so it is worth a look on a site visit.
Often, yes, as long as the existing floor is suitable. That means it needs to be sound and level enough to take the panels. The overlay system is laid over it and your chosen floor finish then goes on top. We check the floor on a site visit and tell you if it needs any preparation first.
Between joists means the wet system is installed between the timber joists of a floor. It suits properties with timber floors where the boards can come up. Insulation goes in first so the heat is directed up into the room, the pipework is laid and pressure tested, and the floorboards are then refitted on top.
Screed needs time to cure before floor finishes go on, and the time depends on the type and depth of the screed. Your builder or screeder will advise, and we plan the installation around it.
We connect the manifold and controls, and systems are pressure tested before the floor goes back over the top. We will set the system up and show you how to use it. For anything specific about what is included at handover on your project, ask us.
Tell us about the project and we’ll come back to you with what we need to know and where to go next.
