Everything you need to know about aluminium spreader plates

When it comes to wet underfloor heating, achieving simple installation and even heat distribution is key. Using aluminium spreader plates is one of the most effective ways to do this.

Whether you’re installing underfloor heating in a retrofit project or working on a new-build property, spreader plates are an excellent way to ensure fast installation and efficient heat transfer.

This guide covers everything you need to know about aluminium spreader plates, including what they are, why they’re beneficial and our top tips for installation.

What are aluminium spreader plates?

Aluminium spreader plates are designed to be used with wet underfloor heating systems.

Typically, they are thin sheets of aluminium featuring evenly spaced grooves which are used to clip and hold an underfloor heating pipe in place. The grooves tend to be omega-shaped or U-shaped.

Our Amber Aluminium Spreader Plates feature double preformed omega-shaped grooves for pipes. They are 1000 x 390mm and suit underfloor heating pipe sizes from 15mm to 16mm in diameter.

How do aluminium spreader plates work?

Aluminium spreader plates are designed to optimise heat distribution for consistent, even warmth.

When warm water flows through the pipes, the aluminium’s high thermal conductivity combined with the evenly spaced channels for the pipe allows heat to spread quickly and uniformly across the plate and subsequently the floor.

This process can speed up the floor’s heat-up time and help to reduce hot and cold spots.

What type of projects are aluminium spreader plates suitable for?

Most commonly, aluminium spreader plates are installed with suspended floor systems and are fitted on top of floor joists or battens. This is why they are often used in first-floor or upper-storey installations.

Typically, they are used for timber joists spaced at the standard 400mm centres, but if the joist spaces vary, this can usually be overcome on site.

They are an ideal alternative for projects where a screeded system isn’t appropriate.

What are the benefits of aluminium spreader plates?

Easy installation

As spreader plates feature pre-formed channels, installing the wet underfloor heating pipe is easy – simply clip the pipe into the grooves. This also keeps it secure to ensure it doesn’t move.

Plus, unlike screeded systems, aluminium spreader plates don’t require additional drying time, making installation quicker and more efficient.

Better heat transfer

As the aluminium efficiently conducts heat from the underfloor heating pipe, it helps to better radiate the warmth upwards into the room above.

Also, this helps to reduce heat-up times, providing a warmer floor more quickly.

Optimised heat distribution

With the plates and preformed channels spaced uniformly, heat distribution is optimised. Not only is it more even, it’s more effective too, with fewer hot or cold spots.

Reduced floor height

As the pipes are installed in the plates which sit within the joist or batten depth, there is minimal impact on the overall floor height, which is especially important for upper floor installations.

Energy efficiency

By improving heat transfer and reducing heat-up times, aluminium spreader plates can help systems run at lower flow temperatures, which is more efficient and cost-effective in the long term.

Lightweight design

Aluminium spreader plates are typically thin to minimise the impact on floor height, which means they are usually lightweight too. This makes installation easier and has minimal impact on the floor’s overall weight.  

Amber’s top tips for aluminium spreader plate installation

1. Plan carefully

Plan your layout prior to installation, ensuring you account for space between the walls and plates to allow the pipe to bend.

2. Prepare the subfloor

Just as with any underfloor heating installation, make sure the subfloor is well-prepared. It should be clean, dry and free from dust or debris.

3. Consider insulation

To maximise efficiency and minimise heat loss, we recommend fitting insulation directly beneath the underfloor heating spreader plate.

4. Fit the plates securely

Whilst the pipes will stay secure when held inside the plates’ preformed grooves, ensuring the plates themselves are installed securely too is key.

We recommend nailing, screwing or stapling the plates onto the top of the floor joist or floor batten for the best results.

5. Optimising heat transfer

We recommend that the spreader plates sit snugly beneath the floorboards.

This will enable the best heat transfer from the plates to the floor above.

Want to find out more about aluminium spreader plates?

For more information about Amber Aluminium Spreader Plates, you can get in touch with a member of our friendly team.

As well as aluminium spreader plates for wet underfloor heating, we also supply a comprehensive range of other wet underfloor heating systems and electric underfloor heating systems – ideal for tradespeople, M&E contractors, specifiers and architects looking to install underfloor heating in their projects.

Alongside our Amber branded products, we are also the leading supplier of DEVI products in the UK and Ireland.

Plus, we offer a free design service, site visits and access to our technical team.