Home » SpiderFix Low-Profile UFH Panel
Close-up of a radiant floor heating system showing orange heating pipes laid over a black grid base, with wet concrete or foam insulation around the pipes and a vertical pipe column.
Close-up of a radiant floor heating system showing orange heating pipes laid over a black grid base, with wet concrete or foam insulation around the pipes and a vertical pipe column.
SKU: SpiderFix12
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SpiderFix Low-Profile UFH Panel

ThermRite
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£6.97 Inc. VAT £5.81 Exc. VAT
£7.30 Inc. VAT £6.97 Inc. VAT £5.81 Exc. VAT
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The ThermRite SpiderFix is a low-profile underfloor heating pipe fixing panel that holds 12mm or 16mm water underfloor heating pipe at an accurate, repeatable layout. Each panel is a robust injection-moulded board made from 100% recycled plastic, measuring 1200 × 600mm and covering 0.72m², with a factory-applied self-adhesive backing that fixes it quickly and cleanly to the prepared subfloor.

Adjoining panels connect with interlocking snap-clips to form one continuous installation surface, and cutting grooves at 50mm intervals make trimming around walls, corners and obstacles straightforward. Pipe can be laid at 50mm, 100mm or 150–300mm centres, so the layout can be matched to the room and the design heat output. SpiderFix suits retrofit and new-build projects over concrete, suspended timber or insulation boards, and is finished with a flexible fibre-reinforced self-levelling compound to give a flat, stable surface and improved heat transfer.

1200 × 600mm
Panel size
0.72m²
Coverage per panel
16.5 / 20mm
Panel height
12 / 16mm
Pipe outside diameter
50–300mm
Pipe centres
100%
Recycled plastic
Choose the panel by pipe size
SpiderFix16 (16.5mm high) is for 12mm pipe. SpiderFix20 (20mm high) is for 16mm pipe. The number in the product code is not the pipe size, so select the variant that matches the pipe in your design.
Pressure test before covering
Fix the pipe in the panels to the approved system design, then pressure test the pipework before applying the levelling compound. Do not cover the pipe until the test has been passed.

Key features

Self-adhesive backing
A factory-applied adhesive backing gives quick, clean and reliable fixing to the prepared subfloor.
Snap-clip connection
Interlocking connectors join adjoining panels securely into one continuous installation surface.
50mm cutting grooves
Cutting intervals every 50mm allow easy trimming and adjustment on site.
Adjustable pipe spacing
Accommodates 50mm, 100mm and 150–300mm centres for flexible pipe layouts.
Low-profile build
At 16.5mm or 20mm high the panel maximises floor-to-ceiling height and helps the system respond quickly.
100% recycled plastic
A durable injection-moulded recycled plastic board that is easy to cut to suit the room.

Variants

Product code
Pipe size
Panel height
Panel size
Route size
SpiderFix16
12mm O.D.
16.5mm
1200 × 600mm
12mm
SpiderFix20
16mm O.D.
20mm
1200 × 600mm
16mm

Technical specification

Panel
Brand
ThermRite
Product type
Low-profile underfloor heating pipe fixing panel
Material
100% recycled injection-moulded plastic
Panel dimensions
1200 × 600 × 16.5mm (SpiderFix16) or 1200 × 600 × 20mm (SpiderFix20)
Coverage per panel
0.72m²
Pipe and layout
Pipe size
12mm O.D. (SpiderFix16) or 16mm O.D. (SpiderFix20)
Route size
12mm (SpiderFix16) or 16mm (SpiderFix20)
Pipe centres
50mm, 100mm or 150–300mm
Cutting grooves
50mm intervals
Installation
Fixing method
Factory-applied self-adhesive backing with interlocking snap-clip connectors
Suitable subfloors
Concrete, suspended timber, or over insulation boards
Recommended covering
Flexible fibre-reinforced self-levelling compound
Application
Water underfloor heating, retrofit and new-build

Recommended build-up above the subfloor

Overall thickness guide
The recommended overall levelling compound plus floor covering thickness depends on the subfloor and the finish. Figures apply to domestic use with normal foot traffic.
Subfloor
Floor finish
Overall thickness
Direct on subfloor
Tiles or wood
20–25mm
Direct on subfloor
LVT, linoleum or carpet
25–30mm
Over insulation boards
Tiles, wood, LVT, linoleum or carpet
30–35mm

Installation overview

Prepare a clean, dry and suitable subfloor, then fix the panels using the self-adhesive backing and connect adjoining panels with the snap-clips. Press the pipe into the panels in line with the design layout, pressure test the system, and cover with a flexible fibre-reinforced self-levelling compound before laying the chosen floor finish.

Heat pump and low-temperature systems
SpiderFix is a pipe fixing panel for warm-water systems, so the output depends on the system design. For heat pump installations, confirm the pipe spacing, flow temperature and room heat loss in the design so the required output can be achieved.

Frequently asked questions

Which SpiderFix panel do I need for 12mm or 16mm pipe?
Use SpiderFix16 (16.5mm high) for 12mm pipe and SpiderFix20 (20mm high) for 16mm pipe. Each panel has a pipe route sized to suit its pipe.
What pipe centres can I use?
The panels accommodate 50mm, 100mm and 150–300mm centres. Choose the spacing from the system design and the required heat output.
What subfloors can SpiderFix be fixed to?
SpiderFix is suitable over concrete, suspended timber or insulation boards, subject to the specified floor build-up. The subfloor should be clean, dry and suitable for the self-adhesive backing.
What do I cover the panels with?
Apply a flexible fibre-reinforced self-levelling compound once the pipe is installed and pressure tested. This creates a flat, stable surface and improves heat transfer ahead of the floor finish.
How do I cut the panels to fit?
The cutting grooves at 50mm intervals allow the panel to be trimmed to fit around walls, corners and obstacles.
How much floor height does the system add?
The panel is 16.5mm (SpiderFix16) or 20mm (SpiderFix20) high. The overall build-up also includes the levelling compound and floor covering, typically 20–35mm in total depending on the subfloor and finish.
BTU & WATT Calculator
Room Dimensions
Room Type
Living Room
Bedroom
Kitchen
Bathroom
Conservatory
Hallway
Glazing Type
Single Glazed
Double Glazed
Triple Glazed
External Walls
0 Wall
1 Wall
2 Walls
3 Walls
4 Walls
Insulation Level
Poor
Average
Good (New Build)
Required Heating
0
Watts
0
BTUs

Documentation

Downloads

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