underfloor heating on joisted floors

CDI > Applications > Uncategorized > Underfloor Heating

We stock and supply a number of floor systems that provide the same or an improved performance as a traditional underfloor heating concrete ground floor, but for suspended floors. Suspended floors are typically constructed using timber or steel beams or joists and are above a void or a room below.

These systems include a steel sheet that reinforces and stiffens the floor (being steel it also spreads the heat across the floor and eliminates any cold spots) and allows for a thin screed or concrete to be used over the top.

These systems include:

Lewis Deck
- Typically around 52mm total depth above the top of the joists, but can be as low as 36mm including the underfloor heating.
Max4 Therm
- From just 15mm total depth above an existing floor that can be timber or concrete including the underfloor heating.
FastSlab Ground Floor
- Complete ground floor system including beams, insulation and floor structure. Underfloor heating pipes are simply clipped to the top of the Lewis Deck before a screed or concrete is applied.
Op-Deck
- Typically a large spanning insulated and high load-bearing ground floor system, also used in load-bearing flat-roof applications. Underfloor heating can be included within the concrete of the system.

Scroll down the page for links to the various systems.

This video compares the Lewis Deck and Gyvlon Thermio+ screed (top left) against aluminium spreader plates (top right).

There is also a comparison between two ground floors, a 40mm Gyvlon Thermio+ screed (bottom left) and a typical 75mm concrete (bottom right).

The second video shows the reaction time of a Max4 Therm floor, this is 15mm in depth and includes an 8mm diameter underfloor heating pipe.

Available Systems

Max 4

We stock and supply a number of floor systems that provide the same or an improved performance as a traditional underfloor heating concrete ground floor, but for suspended floors. Suspended floors are typically constructed using timber or steel beams or joists and are above a void or a room below. These systems include a steel …

Lewis Deck

Lewis Metal Dovetailed Sheeting Deck with acoustic Sylomer resilient strips

We stock and supply a number of floor systems that provide the same or an improved performance as a traditional underfloor heating concrete ground floor, but for suspended floors. Suspended floors are typically constructed using timber or steel beams or joists and are above a void or a room below. These systems include a steel …

FastSlab

We stock and supply a number of floor systems that provide the same or an improved performance as a traditional underfloor heating concrete ground floor, but for suspended floors. Suspended floors are typically constructed using timber or steel beams or joists and are above a void or a room below. These systems include a steel …

Op-Deck

We stock and supply a number of floor systems that provide the same or an improved performance as a traditional underfloor heating concrete ground floor, but for suspended floors. Suspended floors are typically constructed using timber or steel beams or joists and are above a void or a room below. These systems include a steel …

Case Studies

Self Build & Renovations

Lewis Plate Underfloor heating metal decking to a timber frame house in Scotland

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New House, Bellwood Park, Perth, Scotland

FastSlab installation to the ground floor of this listed manor house, for a concrete feel over the basement and to include under floor heating

FastSlab ground floor renovation system to replace an improve a timber ground floor and include underfloor heating. maintains the void

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Ingerthorpe Grange, Markington, Nr Ripon

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FastSlab Renovation Project, Hampshire

Conversion of a mansion house to high quality apartments

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Conversion to apartments by Octagon Homes

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Renovation of the Historic "Redhills" Building, Durham City

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High Performance Acoustic Floors

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Green Port Hull

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FAQs22

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Product FAQ's

Q
What are the Lewis Deck sheet sizes?

A
Q: What sheet sizes are held in stock for delivery within a few days after order? A: We stock 2500mm and 1300mm sheets. These are all 630mm wide and 16mm deep. Deliveries are made via the pallet network directly to site. The smaller sheets are aimed at small bathroom renovation projects and can be supplied in small numbers via TNT. 2.5* and 1.3m sheets allow for the 100mm overlap to occur over a joist, with joist centres being either 300mm, 400mm, 600mm, 800mm*, 1200mm and 2400mm*. (*2.5m sheet only) For larger projects we are able to produce bespoke sheet sizes if required, please get in contact to discuss other options for sheet sizes.

General FAQ's

Q
Why don't my Lewis sheets interlock like they do in the video?

A
Q: Why don't my sheets interlock like they do in the video? A: The sheets have two sides (one printed, one plain), the dovetails on either side are different widths, it is then necessary to alternate the sheets print up and then print down.

Q
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A
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