Siccus: screed-free, dry underfloor heating.
The fifth generation of underfloor heating. The pipe is not buried in wet screed; it sits just under the floor covering with aluminium heat-spreading plates. Heat reaches the surface faster, and the system delivers results with 30–35 °C water.
Uponor Siccus 14 · schematic cross-section. *At least 50 mm in renovation; 56–65 mm in new buildings depending on impact sound insulation.
From wet screed to dry panel.
In the last three generations, plastic pipes ran through wet screed. With Siccus, the pipe moved to a dry panel where aluminium plates spread the heat; light, dry boards are used instead of screed.
Light, thin, fast.
A dry system eliminates the weight, thickness and waiting time of wet screed. That is why it stands out especially in renovation and on timber floors.
Load distribution layer weight
Weight per square metre of layers that do the same job.
Source: Uponor Siccus 14 technical information document.
- Suitable for renovation. A sound, level existing floor covering with sufficient load-bearing capacity usually does not need to be removed.
- On timber floors too. Can be installed on timber joist floors.
- Fast commissioning. Curing and first heating time on dry screed board is 3 days.
- Fast response. The heat is just under the covering; room temperature changes more quickly.
- Low water temperature. Ready to work with heat pumps, solar, wind and photovoltaic sources.
Pipe spacing determines output.
Uponor Siccus 14×2 mm PE-Xa pipe with 25 mm dry screed board (λ = 0.28 W/mK). The narrower the pipe spacing, the lower the water temperature needed for the same heat output.
Heating limit values
| Pipe spacing | qH · W/m² | ΔθH,N · K |
|---|---|---|
| 15 cm | 90,8 | 21,7 |
| 22.5 cm | 81,0 | 25,0 |
| 30 cm | 70,1 | 30,9 |
| Cooling · pipe spacing | qC · W/m² | ΔθC,N · K |
|---|---|---|
| 15 cm | 25,8 | 8 |
Limit curves: θi 20 °C and θF,max 29 °C or θi 24 °C and θF,max 33 °C; in the perimeter zone θi 20 °C and θF,max 35 °C. DIN approved · 7F 009-F.
Open the original design diagramIt heats in winter and cools in summer.
The same pipes both heat and cool, depending on the temperature of the water in the circuit. Because it runs at low temperature, it is a natural match for renewable sources.
Limit heat output; mean water excess temperature 21.7 K.
Cooling output; 8 K difference between room and water.
Other heating solutions
PEXa Underfloor Heating
PEX-a pipe in screed; large spaces and new buildings.
Climate from the ceilingBioiklim
Heating, cooling and hot water in a single radiant system.
Our partnerUponor
Uponor solutions including Siccus, and our shared history.
Underfloor heating without pouring screed.
Let’s do the Siccus calculation together for your projects that need renovation, timber floors or a low build-up height.