Outdoor-sauna insulation should be assessed as part of the complete wall, ceiling and floor assembly. Thickness and material matter, but they do not by themselves establish a U-value, heat-up time, running cost or winter-performance outcome.
How SIP Construction Works
A structural insulated panel generally combines structural facings with an insulating core. Performance depends on the panel design and thickness as well as joints, thermal bridges, openings, moisture control and construction quality [1]. A UK residential case study likewise illustrates that measured building performance depends on the wider fabric, glazing, services, construction and use—not one core number in isolation [2].
Confirmed Lifestyle and Connect Specification
The current Wellness One owner/manufacturer specification confirms that Lifestyle and Connect models use 200 mm-thick walls, ceiling and floor, each incorporating 100 mm of PUR insulation. The 200 mm figure describes the thickness of the construction; the 100 mm figure describes the PUR insulation within it.
This statement applies only to Lifestyle and Connect. It must not be attributed to Therma or another range without a separate current specification.
What the Specification Does Not Prove
The confirmed construction does not, on its own, establish a U-value, airtightness result, heat-up time, electricity use, running-cost saving, maximum-temperature outcome, sub-zero performance, comparative multiplier, durability period or lifespan. Any quantified outcome needs a defined test method, complete tested assembly and relevant operating conditions.
What to Request Before Buying
- The current model-specific wall, ceiling and floor build-up
- Insulation material and thickness
- Junction, membrane, moisture and weather-detail information
- Glazing and frame specification
- Exact heater sizing and UK-market manual
- Test evidence for any stated U-value or quantified performance outcome
- A written installation scope covering the base, access, assembly and electrical responsibilities
Frequently asked questions
How much insulation do Lifestyle and Connect saunas have?
The current Wellness One owner/manufacturer specification confirms that Lifestyle and Connect models have 200 mm-thick walls, ceiling and floor, each incorporating 100 mm of PUR insulation.
Is the wall construction 100 mm or 200 mm?
For Lifestyle and Connect, 200 mm is the confirmed thickness of the wall, ceiling and floor construction, while 100 mm is the PUR insulation incorporated within each assembly.
Does 100 mm of PUR insulation prove lower running costs?
No. Running cost also depends on the complete assembly, glazing, heater, controls, air leakage, weather, target temperature, session pattern and electricity tariff. A quantified saving requires like-for-like test evidence.
References
| Ref | Source | URL |
|---|---|---|
| [1] | Timber Development UK — How much do you know about SIPs? | https://timberdevelopment.uk/how-much-do-you-know-about-sips-structural-insulated-panels/ |
| [2] | Al-Derbi et al. — The Potential of Structurally Insulated Panels to Supply Net Zero Carbon Housing | https://doi.org/10.3390/buildings12122081 |