How to install LowDeck | Circoflo | Underfloor Heating Your Way

How to install LowDeck

Before Getting Started
Make sure the floor is flat, clean and clear of any debris.

Ensure existing slab/floor deck meets at least SR2 (5mm deviation in 2m) requirements for floor regularity (BS8204) and preferably SR1 (3mm deviation in 2m).
Note: the floor finish company may have their own requirements which take precedent.

Timber Floors: LowDeck can float or be mechanically fixed. (Note: undulations in the floor will transfer through the LowDeck).

Solid Floors: A thin layer of non-compressive insulation/insulative matting can be laid prior to fitting LowDeck to provide some resistance when layering over an insulated floor.

Attaching the Manifold
Attach the manifold to the wall as shown, using appropriate wall mounting fittings.

You can arrange the flow and return pipework in a variety of ways, depending on what is best for your installation. The two manifold arms should be within 500mm of each other to allow for the actuators (with 1500mm of cable) to be connected into the 4-zone wiring centre positioned close by.

Lay the Panels
Lay panels in a ‘run’ in front of each other along the room, cutting to fit any corners. Make sure there is a 10mm gap around the edge of the room to allow for expansion.

Cut the final panel in the run to fit and use it to start the next run. Make sure that the pipe channels on the offcut section line up with the neighbouring panels.

Lay the Pipe
Starting at the manifold and working from the edge of the room, push the pipe into the pre-perforated foil channels in a serpentine pattern.

Ensure there is enough pipe exposed from the floor to reach the ports on the manifold. Do not lay the pipe in any areas which will be unheated (such as underneath kitchen units).

Additional channels for flows and returns may be required where the pipes approach the manifold.

Note: If at any point the pipework is kinked, the coil must be replaced.


When returning the circuit to the manifold, cut the pipe with a pipe cutter ensuring that the pipe is long enough to reach the manifold. Label the pipe with flow and return, and number the circuit. This will help when connecting to the manifold.

Note: Once the panels and pipe have been laid, they should be protected with walking boards especially in areas with high levels of foot traffic such as doorways.

Connect the Manifold
Connect the 22mm primary pipework from the heat source.

If you require a mixing unit this will need to be installed in the primary heating pipework along with a standard pump typically located beside the boiler/ heat source.

Fit the monoblocco connectors on to the ends of the pipe and screw onto the manifold by hand. Using a spanner, tighten the connection whilst maintaining upwards pressure on the pipe.

Note: Once connected, it is recommended to insulate all primary pipe work.

Before continuing, complete the connection checklist below:

All manifold joints are tight and sealed
Primary flow and return are connected to the manifold correctly
Isolating valves and drains left closed
Pipes marked with circuit numbers and “flow” or “return”
Ensure that all LowDeck panels butt tightly together with no gaps, but a 10mm gap has been left around the edge of the room for expansion.

Filling the System
If your project uses more than one Circoflo underfloor heating system, lay all of the other systems and connect to the manifold(s) before moving on to filling the systems.

Now follow the commissioning and bleeding instructions on the manifold.

Make sure to fill out the commissioning information on the manifold booklet.