Installing UFH within a suspended timber floor


Wet underfloor heating is fast becoming one of the most popular methods of domestic heating in the United Kingdom. With long-term running efficiency and a key contribution to a minimalistic and modern house design, wet UFH has increased significantly in popularity during the last decade.

It is imperative that you are aware of the correct UFH system for your project, as it is not a ‘one-size-fits-all’ product, there are many variants. Ambiente can provide this expert support, in order to help you realise the benefits of UFH in your property.


What is a suspended timber floor?

When we refer to suspended timber floors, we refer to joisted floor constructions – typically found on the upper floors of a standard house and sometimes on the ground floor of older houses too. The joisted construction usually sits on a wall plate and spans between the various brick walls that form the structure of a house.

Joists are what support the weight of the rooms above them and are overlaid with a structural layer – traditionally pine floorboards, but on more modern properties it would be a chipboard or plywood product in sheet form.

(Below: AmbiPlate 80 system, installed from beneath a suspended timber floor)


underfloor heating in timber flooring


Benefits of installing UFH in joisted floors

Wet UFH systems can be installed within suspended or joisted floors in a number of different ways. Typically this doesn’t in any way affect the floor build-up height, which could be considered the main advantage.

There are 3 main ways to install a UFH system within a joisted floor:

  • From above – if you are working on an open joist void, you can fit the plates from above, to either side of the joists – using our AmbiPlate 30 system
  • From beneath – sometimes, you can’t fit the plates from above. This could be the case in an old property where the existing floorboards cannot be disturbed. Another example could be where a new house has the floor deck pre-installed – i.e, the complete floor structure is craned onto site, with the structural layer already installed. Our AmbiPlate 80 system is the system to use here – installed from beneath
  • Within the structural floor layer – our AmbiChipboard system is a unique method of installing the UFH within a structural floor layer – 12mm UFH pipework is installed within a pre-routed 22mm chipboard panel, which is laid directly over the joists

See below more details on all of the systems mentioned above.

Need more advice on which system would suit your project? Give us a call today – we are a supplier of underfloor heating that invests in new innovations and comprehensive designs, to make sure we only offer systems that work to the required standard in any given situation.


Best wet underfloor heating for suspended timber floor?

You can learn even more about the best underfloor heating systems for joisted floors from our experts in a previous article.

You can also find out more about some of our main systems for suspended floor systems below:


suspended UFH system

Ambiplate 20

The AmbiPlate 20 system is designed to suit battened floor build ups but can be easily adapted to suit sprung sports floors, acoustic batten floors and over-battened floors. Before the underfloor heating system is installed, insulation should be laid between the battens and should be laid as close as possible to the underside of the pipework to maximise heating output.

The system consists of aluminium diffuser plates being fixed directly on to the battens. The plates contain grooved channels into which the underfloor heating pipework is installed in continuous lengths and piped back to the underfloor heating manifold.

The reflective properties of the aluminium diffuser plates mean that any heat is efficiently pushed up through the subfloor layers for maximum heat output. The nature of the system means that it has a quicker response than a traditional (screed) UFH system.

System Overview

  • Heat output up to 75W/M2
  • Designed for battened floors
  • No impact on floor build up
  • Reflective aluminium means maximum heat transfer
  • Quick response time


wet UFH system


Ambiplate 80

The AmbiPlate 80 system is a unique underfloor heating system designed for joisted floors, that can be fitted from beneath an installed floor layer. The system consists of aluminium diffuser plates, which help to reflect the heating up through the floor layers.

These plates are fixed to the underside of the flooring layer, with the UFH pipework clipping into the channels that run down either side of the plate. With no impact on floor-to-ceiling height, and no need to disrupt original floorboards, this system is revolutionary.

The AmbiPlate 80 system can also be used when fitting plates from above, but where the joist widths are varied and inconsistent. In this scenario, using a regular width plate makes installation very difficult, but simply lay the AmbiPlate 80 system over the joist and fix from above.

Although the pipe centres may vary slightly, it ensures two pipe runs per joist void for equal heat distribution within the room.

As with all diffuser plate systems, it is essential to insulate the joist void well, with at least 100mm of mineral wool type insulation or 50mm of rigid board insulation, held up tight to the underside of the plate.

System overview

  • Heat output up to 70W/M2
  • Unique ‘fit-from-beneath’ system
  • No impact on floor build-up
  • Reflective aluminium means maximum heat transfer
  • Quick response time


UFH benefits



This is a variant of the AmbiClip system which relies on the heating of the air void to heat the space above it –  this does limit the actual output of the system in some circumstances.

Insulation is laid between the battens (25mm minimum) and clip rail sections are laid across the width of the void. Pipework is then run up and down the voids, clipping into the clip rail to keep it consistent. This is a low-cost solution and is ideal in new-build situations where the insulation level is exceptional.

System overview

  • Heat output up to 60W/M2
  • Designed for new build or refurbishment projects
  • Void heating system


Can you retrofit underfloor heating into a suspended timber floor?

The short answer is yes, you can. There are a number of parameters that will determine the scale of works that this will involve, and which will also influence the decision you make as to which system best suits your project.

Typical challenges in retrofit scenarios include floor layers that cannot be disturbed, uneven joist spacings throughout a property and minimal floor-to-ceiling height.

The benefit of using a plated UFH system as described above is that these have no impact on the build-up height within a property. The benefit of using a grooved chipboard UFH system is that it can be laid over joists, regardless of if they are irregular in their spacing.

Retrofitting UFH can be challenging, but by taking a consultative approach, Ambiente will assist you through every process from initial specification through to after-sales support.

By using our in-depth range of resources, you can find out all you need to know about installing our UFH systems and how to get the most potential from them.

A project we provided UFH for at St Lawrence Terrace in London was fitted with the Ambiplate 80 on the upper floors. As the existing floors could not be lifted or disturbed, AmbiPlate 80 was the perfect solution, allowing installation of the UFH system from beneath.


retrofitting underfloor heating solutions


Require wet underfloor heating for your project?

Ambiente specialises in the design, manufacture and supply of wet UFH systems. Our hard work and development have placed us at the forefront of the market. Combining integrity and design ensures that we meet the requirements of consumers and provide the solutions that contractors require for a diverse range of projects.

We strive to provide an underfloor heating system to meet every project – and if we do not have a system in our range, we have the facility to develop bespoke underfloor heating systems to meet challenging parameters.

Please call us today for advice on the best underfloor heating for you project – 01707 649 118 or email


Did you find this article useful? You may enjoy:

Which is the best underfloor heating system for joisted floors?

What should you consider before installing ‘retro fit’ underfloor heating?

What should you consider before installing underfloor heating with an acoustic layer?


This article was written by Robert Tuffin.

Robert is the General Manager at Ambiente and has been working in the underfloor heating industry since 2012.