Underfloor heating pipe centres: 100, 150 or 200mm?

October 22, 2026

Short answer: Use 150mm pipe centres for most rooms, 100mm where the room loses a lot of heat or you want the lowest flow temperature, and 200mm only in well-insulated rooms with low heat loss. Closer pipe gives more heat at the same water temperature: one maker quotes 91W/m² at 100mm centres against 76W/m² at 200mm, both at a 50°C mean water temperature. Many designs also run a tighter band, about 1m wide, along cold outside walls and glazing.

Pipe centres (also called pipe spacing or pitch) is the distance between the middle of one pipe run and the next. It sets how much heat the floor can give out, how evenly the surface warms, how much pipe you buy and how many manifold ports you need. It is one of the few design choices you cannot change once the screed or boards are down.

This guide explains how spacing changes output, which spacing suits which room and floor system, where to use mixed spacing, and what the choice does to your kit list. For the pipe quantity sums themselves, see how much underfloor heating pipe you need.

Does closer pipe spacing give more heat?

Yes. Halving the spacing from 200mm to 100mm raises the output by roughly a fifth at the same water temperature, not by double. The floor surface, not the amount of pipe, is what gives heat to the room, so each extra metre of pipe adds less than the one before.

Pipe centres	Output at 50°C mean water	Pipe per m²
100mm	91W/m²	10m
200mm	76W/m²	5m

These are published figures for one maker's screeded panel system. Your own figures depend on the screed, the floor finish and the room temperature, but the pattern holds for every wet system: twice the pipe for about 20% more heat.

The useful way to read this is the other way round. For the same output, closer pipe lets you run cooler water. That matters most with a heat pump, which works more efficiently at a lower flow temperature. Our guide to underfloor heating with a heat pump covers flow temperatures in detail.

There is also a ceiling. BS EN 1264 limits the floor surface to 29°C in occupied areas, which gives about 100W/m² in a 20°C room whatever the spacing. Closer pipe helps you reach that limit at a lower water temperature. It does not let you go past it.

Which pipe centres should I use for each room?

Pick the spacing from the room's heat loss per m² and your heat source. Start at 150mm and move closer only where the room needs it.

Room or situation	Typical centres	Why
Most rooms, boiler	150mm	Good output, sensible pipe use
Most rooms, heat pump	100 to 150mm	Lower flow temperature
Large glazing, bifolds	100mm band	High local heat loss
Older, poorly insulated	100mm	More output needed
Bathroom	100 to 150mm	Warmer set point, small area
Well-insulated new build	150 to 200mm	Low heat loss
Hall, landing, utility	150 to 200mm	Lower set temperature

Treat this as a starting point. The proper check is the room heat loss: work it out in watts, divide by the heated floor area and compare it with the floor's output at your flow temperature. Our guide to heat loss and UFH output shows how.

Uponor's installation guide uses 200mm as the standard spacing for 16mm pipe in screed and says spacing can drop to half that in high heat loss areas. Polypipe's panel system allows 300mm with larger 18mm pipe. Most UK homes on 16mm pipe sit between 100 and 200mm.

What is a perimeter or edge zone?

A perimeter zone is a band of tighter pipe, up to about 1m wide, along an outside wall, patio door or full-height glazing. It puts extra heat where the room loses most and stops a cold strip forming by the glass.

BS EN 1264 allows the floor surface in an edge zone to run up to 35°C, because nobody sits there for long. That gives up to about 175W/m² in the band, against about 100W/m² in the rest of the room.

Mark the cold edges. Outside walls with large windows, bifold or patio doors, and rooflit areas.
Set the band width. Up to 1m from the wall, typically one or two metres of pipe run deep.
Lay the band first, at 100mm. Start the loop at the cold edge so the hottest water reaches it first.
Continue at 150mm. Carry on across the rest of the room in the same loop.
Recount the loop length. The band adds pipe, so check the loop still stays under 100m for 16mm or 80m for 12mm.

A band is cheaper than laying the whole room at 100mm and gives most of the benefit. In a 5 × 4m room, a 1m band at 100mm along the 5m glazed wall adds about 17m of pipe compared with 150mm throughout. Laying the whole room at 100mm adds about 66m.

Can I choose any spacing with my floor system?

No. Clipped screed systems let you choose any spacing, but routed boards fix it at the factory. Check the board before you design the loops.

Floor system	Spacing	Notes
Clips or clip rail in screed	Any	Set out on site
Castellated panels	Steps of the boss pattern	Pipe sits between bosses
MaxHeatChip chipboard	150mm	Grooves routed in
MaxHeatPanel XPS board	150mm	Grooves routed in
MaxHeatDeck board	150mm	Grooves routed in
Spreader plates	Set by plates and joists	Plate width matters

On a routed board you cannot add a 100mm band, so the board system has to suit the room as designed. If a room needs more output than 150mm routed board gives, the options are a different floor system, a lower-tog floor finish, a higher flow temperature or less heat loss. Our guide to floor systems explained compares them.

How does spacing change the cost and the kit?

Closer spacing means more pipe, more loops and more manifold ports. Here is one 20m² heated room in 16mm PERT-AL-PERT pipe, with the manifold 4m away, at each spacing.

Centres	Pipe and loops	Coil and price
100mm	200m in floor, 3 loops	300m, £214
150mm	134m in floor, 2 loops	200m, £143
200mm	100m in floor, 2 loops	150m, £107

Each loop has 8m of tails and an allowance of 10% plus 1m. Prices are inc VAT, October 2026. The third loop at 100mm also needs one more manifold port, one more actuator, two more Eurocone cores and two more support bends, which adds about £26 more on a Dualmix manifold.

So going from 150mm to 100mm in this room costs about £97 more in kit for roughly 20% more output. Going from 150mm to 200mm saves about £36 but gives less output and a less even floor. On a whole floor, those sums multiply, which is why a perimeter band is often the better buy.

Does wide spacing make the floor feel stripy?

It can. With wide spacing and a thin floor build-up, you can feel warm lines over the pipes and cooler strips between them. The surface evens out when there is more material, or a metal layer, between the pipe and the finish.

Screed: 65mm or more of sand and cement screed spreads heat well, so 150 to 200mm feels even.
Overlay and routed boards: thin build-ups rely on a foil or aluminium layer, such as the 100 micron foil on MaxHeatPro panels, to spread heat between runs.
Joisted floors: aluminium spreader plates or a foil-backed top board do the same job under the floor deck.
Hard finishes: tiles and stone show stripes more than carpet, which smooths them out.

If you want 200mm centres on a low-profile system, check the maker's output figures first. In most overlay jobs 150mm is the practical maximum.

How tight can the pipe bend at the end of each run?

A 16mm pipe should not be bent tighter than 5 times its outside diameter, which is an 80mm radius. Pipe makers state this minimum for both PE-RT and multilayer pipe.

That has a knock-on effect at close spacing. A straight 180° return at 100mm centres would need a 50mm radius, which is too tight. Installers get round it in two ways:

Keyhole return: the pipe swings wider at the end of the run, then comes back into line at 100mm.
Spiral layout: flow and return runs alternate, so most turns are made at twice the spacing and the bends are gentler.

Use a bending spring or pipe bender for tight bends on multilayer pipe, and never kink the pipe. A kinked loop must be replaced, not straightened.

Products for this job

PERT-AL-PERT Multilayer UFH Pipe
5-Layer PERT-EVOH UFH Pipe 16mm
Self-Adhesive Pipe Clip Rail (1m), for any spacing in screed
MaxHeatUFH Castellated Floor Panel
MaxHeatChip Grooved Chipboard Panel, 150mm grooves
External Bending Spring
All UFH pipe

Try different pipe centres free with MaxHeatUFH ProLoop. Add your rooms and floor type, set the spacing per room, and see the loop design, pipe, ports and full kit list with prices. Start your design

Frequently asked questions

What is the standard pipe spacing for underfloor heating?

150mm is the most common choice in UK homes on 16mm pipe. Some makers use 200mm as their standard for screed and reduce it in high heat loss areas.

Is 100mm or 150mm better for a heat pump?

100mm gives more output at the same water temperature, so it lets the heat pump run cooler. Use it where the heat loss is high. In a well-insulated room, 150mm is often enough.

Can I use different pipe spacing in one room?

Yes. A common layout is a 100mm band along cold outside walls and glazing, then 150mm across the rest of the room, all in the same loop.

What is the maximum pipe spacing for underfloor heating?

For 16mm pipe in a home, 200mm is a practical maximum. Wider spacing, such as 300mm, is used with larger pipe in some screed systems, but the floor gives less heat and can feel uneven.

Does pipe spacing affect how fast the floor warms up?

A little. Closer pipe puts more heat into the floor, but warm-up time depends far more on the floor build-up. A thick screed takes hours, an overlay board much less.

Can I change pipe spacing on routed boards?

No. MaxHeatChip, MaxHeatPanel and MaxHeatDeck boards have grooves at 150mm centres. If a room needs closer spacing, use a clipped or castellated screed system there.