Fastwarm® 20mm Tile Backer Boards offer an excellent mid-thickness solution for projects where both thermal insulation and subfloor stability are critical. These boards are specifically engineered to work alongside our Fastwarm® 150w/200w/cable electric underfloor heating systems.
Despite their added thickness, they remain lightweight and are easily cut with a craft knife, making them perfect for installation in larger rooms or renovations where extra insulation is desired.
Boards can be laid over timber with mechanical fixings or bonded directly to solid substrates using flexible tile adhesive.
- Waterproof – Fully waterproof construction, approved by Ultra Tile adhesive manufacturers.
- High Insulation Performance – Thermal conductivity of just 0.034 W/mK helps minimise heat loss.
- Excellent Sound Insulation – Improves acoustic comfort in any room.
- Ultra-Lightweight & Easy to Cut – Easily trimmed on-site with a utility knife.
- Strong & Durable – Supports compression loads up to 30 tonnes per m².
- Multi-Surface Application – Suitable for walls and floors (follow correct installation methods).
- Flexible Installation Options – Mechanically fix to timber or bond to solid subfloors with adhesive.
- Standard Size – Each board measures 1200 x 600 mm (0.72m²).
This board is 20mm thick — perfect when higher thermal resistance or build height is required. A 10m² area will generally need 14 boards.
Please note: Always use flexible tile adhesive and secure timber floors with mechanical fixings every 300mm.
Need a different thickness? Other options available: 6mm | 10mm | 12.5mm | 30mm | 50mm
Choose the board that best balances insulation performance with your floor build height.
| Thickness | 6mm, 10mm, 12.5mm, 20mm, 30mm & 50mm |
|---|---|
| Board Dimension | 1200mm x 600mm |
| Material Type | Extruded Polystyrene, Fibreglass Mesh & Cementitious Coating |
| Thermal Conductivity | 0.027 W/mk |
| Material Density | >30 kg/m3 |
| Compression Strength | 30 t/m2 |
| Vertical Tile Weight Load | 50 kg/m2 |
| Moisture Absorption | <0.1 vol % |
| Euroclass Fire Rating | B Euroclass |
Delivery Options
2-3 working day delivery
Next working day
Next working day before 10:30
Saturday Delivery
Delivery cut off times
Our daily cut-off time for dispatch is 4:30pm Monday–Thursday and 4:00pm on Fridays. Orders placed before the cut-off time will be dispatched for next working day delivery (if this option is selected). Orders placed after 4:00pm on Friday will be dispatched on Monday for Tuesday delivery.
Bank holidays may affect these delivery times, so please contact our team if unsure on 01268 744479
Other Delivery Options
PRE-10:30AM and Saturday Delivery services are available, but orders must be placed before the relevant cut-off times.
NOTE: All orders placed on a Friday will be delivered on the following Monday (unless its a bank holiday), unless a Saturday Delivery service is selected and paid for before the 4:00pm Friday cut-off.
Delivery outside the UK
Delivery outside mainland UK may be arranged by prior agreement. You will be advised of the delivery charge before dispatch, at which point you can decide whether you wish to proceed with your order.
Important: Our deliveries rely on third party couriers, so, whilst we make every effort to deliver your order on the specified date and time, unfortunately there may be occasions when this will not be possible due to external influences. Due to this we strongly recommend you ensure you have received your order before any tradespeople/builders are scheduled to commence work.
Still Unsure? Talk to an expert
If you need any guidance or further information our highly experienced team are on hand to help.
Get in touch using our contact form or give us a call on 0800 023 4203 or 01268 744 479.