Renu Therapy - Cold Stoic Pure
The cedar-wrapped premium reference, built like a Japanese onsen.
A cedar-wrapped horizontal plunge that hits 34°F and holds it forever - the closest production unit to a custom onsen.
If the Plunge Pro is the Toyota of cold plunges, the Renu Cold Stoic Pure is the Lexus LX. Same chillered category, completely different conversation. Cedar exterior, horizontal full-body immersion, hits 34°F (the Plunge bottoms out at 39°F), 60-month tub warranty, and a presence in a room that other tubs simply don't have.
It's also nearly 2x the price. For a buyer making a single $15K decision on home recovery infrastructure, that math can absolutely work - but only if the cedar aesthetic and sub-39°F temperatures actually matter to you. If they don't, you're paying for jewelry.
The service network is smaller than Plunge's, the 320lb empty weight means you need to think about indoor floor loading, and cedar requires periodic re-treatment outdoors. None of those should disqualify a serious buyer; all of them should be priced into your decision.
Premium-aesthetics buyers who want sub-39°F temperatures, the longest warranty in the category, and a tub that reads as architecture.
You're budget-constrained, want apartment-friendly install, or don't care about premium materials.
Pros
- Hits 34°F - coldest mainstream production target
- 60-month tub warranty (industry-leading)
- Cedar - premium aesthetic, naturally antimicrobial
- Horizontal full-body immersion
- Made in USA
Cons
- Premium price - 1.5-2x Plunge Pro
- Heavy (320lb empty) - floor loading matters
- Cedar requires periodic re-treatment outdoors
- Smaller service network than Plunge
Specifications
Most often compared with
Where this fits
Renu Therapy Cold Stoic Pure cross-shops across several editorial surfaces - the full brand catalog, the buyer-intent tags this item carries, the price band it qualifies for, and any execution playbook that uses it.
Renu Therapy Cold Stoic Pure - buyer FAQ
Renu Cold Stoic Pure vs Plunge Pro - which one should I buy?
Two different purchases. Plunge Pro at $8-10K is the safe default with the largest service network and 39°F operation. Renu Cold Stoic Pure at $14-15K is the cedar-wrapped premium reference with 34°F floor and a 60-month tub warranty. If you want the safest single-purchase, Plunge. If cedar aesthetics + sub-39°F temperatures + premium warranty justify nearly 2x the price for your buyer profile, Renu.
Why does 34°F matter vs Plunge's 39°F?
Marginal benefit for most users. The cold-exposure protocol research (Huberman, Søberg) clusters around 50-59°F as the threshold for autonomic activation. 39°F is plenty cold for the typical 2-5 minute session. 34°F is what Wim Hof-tier practitioners chase - colder = shorter session for equivalent effect. For most longevity readers, the cedar aesthetics and warranty matter more than the 5-degree temperature gap.
How much maintenance does the cedar require?
Annual exterior re-treatment if outdoors (cedar sealer, ~$30-60 in product + 1-2 hours of work). Indoor installations don't require treatment. Cedar is naturally antimicrobial and rot-resistant, so neglected exteriors weather rather than fail structurally - just looks worse over time. Water chemistry maintenance is the same as any chillered tub (UV-C + filter, water change every 4-6 weeks).
Does the 320 lb empty weight cause floor problems?
Filled (water + cedar + chiller + user), the Cold Stoic Pure runs ~1,200-1,400 lb on a 25 sq ft footprint = ~50-60 psf. Standard residential floors handle this fine on the ground floor or basements. Second-story installations need an engineer to verify floor joist capacity - some old joist systems max at 40 psf live load. If installing on a second floor, get a structural sign-off before committing.
Is the warranty really 60 months?
On the cedar tub itself: yes, 60 months (5 years) - industry-leading. The chiller component is covered separately at 36 months (3 years) which is still longer than most competitors. Renu has the deepest warranty stack in the category. Service network is smaller than Plunge's, so warranty claims may take longer to resolve - but the coverage breadth is real.