Underfloor Heating GuidesGuide · Design

Where should the underfloor heating manifold go? Location, height and cupboard size

Where to put a UFH manifold: central to the rooms it serves, in an accessible cupboard, at least 300mm above the floor, with cupboard sizes by port count and the mistakes to avoid.

9 October 2026 · 10 min read

9 October 202610 min read

Short answer: Put the manifold as near the middle of the rooms it serves as you can, in an accessible cupboard on an inside wall, such as under the stairs, a utility, an airing cupboard or a cloakroom. Makers ask for at least 300mm between the finished floor and the lowest part of the manifold or pump set, and one asks for 100mm clear above and to each side. Aim to keep the feed pipes from the manifold to each room under about 20m for 16mm pipe, and fit one manifold per floor.

The manifold is where every underfloor heating loop starts and finishes. Its position decides how long the feed pipes are, how many pipes crowd through the hall outside it, how easy it is to balance and service, and whether rooms near it overheat. It is one of the first decisions in a design, because every loop is drawn back to it.

This guide covers where to put a UFH manifold, how high to mount it, how big the cupboard needs to be and the mistakes that cause trouble later. For how many ports you need, see how many manifold ports do I need.

Where is the best place for an underfloor heating manifold?

The best place is central to the heated rooms, where it can be reached for servicing but is out of sight. Manufacturers name the same spots:

Under the stairs: often central in a house and close to the hall, where many loops start.
Utility room: handy for the boiler or heat pump pipework, but check it is not in a corner of the house.
Airing cupboard: works well on an upper floor.
Cloakroom or coat cupboard: common in new builds with an open-plan ground floor.
Plant room: a good choice in a self-build if it sits near the middle of the plan.

One manufacturer says to fix the position at the start of the design. A central manifold gives loops of similar length, which makes the system easier to balance. Guidance from one design firm also suggests keeping it away from bedrooms and living rooms, because pumps and actuators can be heard.

One manufacturer's instructions say its manifold pump set is not suitable for fitting outside, so keep it indoors and in the heated part of the building.

Why does manifold location matter so much?

Because the feed pipes between the manifold and each room count towards the loop length. A manifold in the wrong place adds pipe, adds loops and can overheat the areas the feeds pass through.

Here is a worked example. An 18m² room needs about 90m of pipe in the floor. With the manifold 15m away, the flow and return feeds add 30m, so the room needs two loops and about 150m of pipe in total. With the manifold 4m away, the same room stays on one loop.

Manifold distance	Feed pipe added	Result for an 18m² room
4m	8m	One loop
15m	30m	Two loops, about 150m of pipe

A common guideline is to keep feeds under 20m for 16mm pipe and under 15m for 12mm pipe. Makers also cap the whole loop. Manufacturer guidance gives about 100m per circuit for 16mm pipe and 60m for 12mm pipe, so a long feed eats into the pipe you have left for the room itself.

Feeds also give off heat wherever they run. A central manifold with many loops packs pipes closely in the hall and nearby rooms, which can overheat those spaces with heat the thermostat cannot control. For systems with five or more loops, the advice is to sleeve the flow feeds in conduit where the system allows it. Our pipe conduit for 16mm pipe does that job.

Where should you not put the manifold?

Avoid putting it next to the boiler just because the boiler is there. Boilers often sit in a utility on an outside wall, so every loop has to start from one corner of the house and the feeds bunch up in a small area.

A corner of the building: long feeds to the far rooms, more loops, uneven balancing.
Bedrooms and living rooms: pump and actuator noise.
Outside or in an unheated garage: One manufacturer says its pump set is not for external fitting.
Behind fitted units with no access: the manifold needs servicing, venting and balancing.
Below the level of the loops it serves: on sealed systems where feeds run through a ceiling void, the manifold must always be higher than the system, so air can be vented from it.

Moving the manifold to the centre may mean longer primary pipes from the boiler or heat pump. It is still the recommended approach, because it means fewer feeds, less overheating and lower cost overall. Primary pipe is one run of flow and return. Feeds are two pipes for every loop.

How high should a UFH manifold be mounted?

Mount it so the bottom of the manifold, or of the pump set if one hangs below it, is at least 300mm above the finished floor. That leaves room for the loop pipes to bend up into the connections without kinking.

Source	Height guidance
Manufacturer A	Minimum 300mm from floor to the lower return bar
Manufacturer B	Normally at least 300mm above the floor
Manufacturer C	Minimum 300mm from finished floor to the lowest part, such as the pump set

Take the highest figure your manifold maker gives. In practice, a little more height makes the pipe bends easier and gives you space to work on the ball valves and pump. Use a pipe support bend on each pipe where it rises out of the floor, so the bend holds its shape.

How big does a manifold cupboard need to be?

Allow roughly 600mm of width for a small manifold with a pump set and about 1m for a 10 to 12 port manifold with a pump set, plus clearance around it. Height is set by the manifold and the 300mm gap below it, so most cupboards need to be at least full knee-to-shoulder height.

Purpose-made cabinets give a good guide to the space needed. These are one maker's surface-mounted cabinets for stainless steel manifolds, all 585mm high and 145mm deep:

Cabinet width	With pump set	Without pump set
350mm	Not suitable	2 ports
585mm	2 to 5 ports	3 to 7 ports
810mm	6 to 9 ports	8 to 12 ports
980mm	10 to 12 ports	Not listed

Another maker's in-wall cabinet follows the same pattern: 600mm wide for 2 to 3 ports, 750mm for 4 to 6, 900mm for 7 to 9 and 1050mm for 10 to 12. Manufacturer guidance notes that a pump set needs at least 140mm depth.

On top of the manifold itself, one manufacturer asks for 100mm clear above and on each side for maintenance. Remember the wiring centre too. It usually sits beside or above the manifold and needs its own space and a power supply. See our wiring centres.

If the cupboard is too narrow for the pump pack to sit on the end of the manifold, a 90° elbow connector set lets you mount the pump and blending unit at right angles, for example round a corner in the cupboard, with no extra pipework.

Do I need a manifold on each floor?

Usually, yes. Homebuilding and design guides all say one manifold per floor is the normal layout, with the primaries running up between floors.

A large single floor may need two manifolds if one central position would still leave very long feeds, or if you need more loops than one manifold handles well. One manufacturer says that with loops of 80 to 100m, a manifold should ideally have no more than 12 ports.

If the ground floor has underfloor heating and the first floor has radiators, the radiators can usually stay on their own circuit. A separate manifold for them is optional.

What else needs to reach the manifold position?

Plan these at the same time as the location, because they all have to arrive at the same cupboard:

Primary flow and return from the boiler, cylinder or heat pump, with 1" ball valves so the manifold can be isolated.
A fused spur for the wiring centre and pump, fitted by an electrician.
Thermostat cables from each room, or a clear radio path for wireless thermostats.
Somewhere to drain and fill, since the manifold is where you flush, fill and vent the loops.
A clear route for the feeds through walls or the insulation layer. Route through walls to reach rooms with as few feeds as possible.

Gas boiler connections must be made by a Gas Safe registered engineer. For the pipework and valves at the manifold itself, see connecting a UFH manifold.

Design your UFH system yourself in 3 minutes with MaxHeatUFH ProLoop and get an instant quick design and quote. Try the manifold in different places and see how the loops change. Start your design

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Frequently asked questions

Can the UFH manifold go in a different room from the boiler?

Yes, and it often should. Run the primary flow and return from the boiler or heat pump to a central manifold. That is usually better than starting every loop from the boiler's corner of the house.

What is the minimum height for a UFH manifold?

Most makers ask for at least 300mm from the finished floor to the lowest part of the manifold or pump set. Some ask for 400mm or more, so follow the figure for your manifold.

Can a manifold go under the stairs?

Yes. Under-stairs cupboards are one of the most common positions, because they are often central and close to the hall where many loops start. Check there is enough height and width for the manifold, pump set and wiring centre.

How far can the manifold be from the rooms?

A common guideline is to keep feeds under 20m for 16mm pipe and 15m for 12mm pipe. The feed counts towards the loop limit, which manufacturer guidance gives as about 100m for 16mm pipe.

Can I put the manifold in the loft or a basement?

A manifold below the loops is a problem for venting, and the manifold must be higher than the system where feeds drop from a ceiling void. A loft is usually too far from the floors it serves and may be cold. A central cupboard on the floor being heated is the better choice.

Does the manifold need to be in a cabinet?

No. It can be fixed to a wall inside any cupboard with enough space. Cabinets are useful where there is no cupboard, or where the manifold has to sit in a hall or a room.

Will the floor near the manifold get too hot?

It can, where many feeds run close together. Keep the manifold central, route feeds through walls where you can, and sleeve the flow feeds in conduit on larger systems.

Sources: Homebuilding: UFH manifolds