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If you're tall, shop by the water area. The 3 tubs here differ by more than a foot inside: on the makers' pages read November 10, 2026, the Renu Aurelius lists 62.5 inches of interior length, the Sun Home Cold Plunge Pro Titan lists 58.5 inches and the deepest basin at 34.3 inches, and the Renu Siberian Pro lists 48 inches inside an 80-inch body. A long exterior can still be cramped where you sit, so check the seat, entry and intended posture too.
The Renu Aurelius, Renu Siberian Pro and Sun Home Titan are 3 different layouts. Start with the Aurelius if you want to recline; the Siberian Pro and Titan trade some of that length for depth. We compared the makers' published figures and haven't sat in any of these tubs. Lifespan Vault may earn a commission from qualifying purchases through product links.
Quick answer
- You want to recline: Aurelius, $11,999 in every color and deck combination on November 10, 2026, has a published water-area length of 62.5 inches.
- You prefer a shorter, deeper tank: Siberian Pro, $15,499 or $15,819 with the spa light, publishes a 48-inch tank length and 30-inch depth.
- You want a long, deep tank with a bench: Titan, $14,599 on sale against a $15,399 regular price, publishes a 58.5-inch interior length and 34.3-inch depth. Sun Home's page gave no ship date on November 10, so ask for one before ordering.
Interior space by the numbers
| Product | Published water-area/interior dimensions | Exterior footprint | Price on November 10, 2026 |
|---|---|---|---|
| Aurelius | 62.5 x 26.75 x 26 in | 70 x 50.75 in | $11,999 |
| Siberian Pro | 48 x 24 x 30 in | 80 x 34.375 in | $15,499; $15,819 with spa light |
| Titan | 58.5 x 28.3 x 34.3 in | 92.4 x 35.4 in | $14,599 sale; $15,399 regular |
Dimensions and prices are the makers' published figures, read from each product page on November 10, 2026. We didn't measure these tubs. Contours, benches, fixtures and the actual waterline can reduce usable space. Renu prints an asterisk beside both of its body widths, so ask what it covers and get the current dimension drawing before planning a tight access route. Sources: Aurelius, Siberian Pro, Titan.
Aurelius: start here for a reclined layout
The Aurelius has the longest published water area of the 3 inside the shortest body, at 70 inches. That body is also the widest, at 50.75 inches, so the tub with the most legroom needs the most care on the way in.
Height is only one measurement. Torso length, leg length and shoulder width can change how 2 equally tall buyers fit the same tub, so ask how the seat, foot supports and intended waterline set your position.
Where it gives ground is width on the property. Measure the gate and the final position separately, because a space can fit the installed tub and still offer no route for getting it there. Renu lists the Aurelius at 297 lbs dry, ships it in 6 to 8 weeks and delivers free to the curb in the contiguous US, so moving it off the pallet is yours to arrange. Ask for the shipping dimensions before booking movers.
Siberian Pro: distinguish body fit from exterior size
The Siberian Pro's body is 10 inches longer than the Aurelius and its tank is 14.5 inches shorter. The tank is also 4 inches deeper, at 30 inches, which points to a more upright position. The practical question is whether that gives your legs, torso and shoulders enough room at the intended fill level.
A stated maximum user height is a first screen and can't promise comfort. Confirm any weight guidance too, and don't read a marketing photograph as a load rating.
Handling and foundation matter more here than with the Aurelius. Renu lists the Siberian Pro at 650 lbs dry and about 1,500 lbs filled with 120 gallons, before anyone gets in. A deck or raised floor needs a site-specific assessment; dividing the total by the visible rectangle doesn't establish structural suitability. Renu's page also lists a 1-year warranty and 4 to 6 weeks to ship for this tub, against the 5-year limited warranty printed on the Aurelius page.
Titan: check the seat and the delivery date
The Titan has the longest body here at 92.4 inches and the deepest interior at 34.3 inches, holding 238 gallons. Neither figure tells you how the built-in bench positions your body. Ask Sun Home for the bench geometry and normal operating waterline, then compare them with your seated measurements.
The Titan launched as a preorder in late August 2026. When we read Sun Home's page on November 10, 2026, it showed an Add to Cart button and no preorder wording, ship date or lead time, and it said free gifts ship as stock allows. Ask for an order-specific ship date for the tub before paying, and a separate one for any promotional items.
Where it gives ground is the space required outside the water. Sun Home asks for a level, structurally sound surface with drainage nearby and room for airflow at the sides and in front of the chiller, and its page lists no weight for the Titan. Plan the entry route, lid handling and service access as part of the installation.
The price premium in plain numbers
At the November 10 prices above, the Titan costs $2,600 more than the Aurelius on sale and $3,400 more at its regular price. The Siberian Pro costs $3,500 more without the spa light. Spread over an assumed 500 uses:
| Comparison with Aurelius | Extra equipment spend | Difference per assumed use |
|---|---|---|
| Titan at the $14,599 sale price | $2,600 | $5.20 |
| Titan at the $15,399 regular price | $3,400 | $6.80 |
| Siberian Pro at $15,499, no spa light | $3,500 | $7.00 |
The calculation is extra purchase price divided by 500. It leaves out installation, taxes, electricity, repairs and maintenance, and it doesn't predict durability or say which tub fits you. A cheaper tub you can't sit in comfortably saves nothing, and a higher price doesn't buy a better fit.
Don't rank these by dollars per interior inch. Depth, seat shape and posture matter too much for one measure to pick a winner. Use the table to size the premium after you've worked out which layouts suit you.
A fit check before you pay
Record the posture you want, the body measurements relevant to it and the manufacturer dimensions you still need. Tape the external footprint on the intended surface, then mark access and service space separately. Don't test fit by climbing into an improvised or unsuitable container.
Ask for a current drawing showing the inside walls, bench, foot supports and normal fill line. If a showroom demonstration is available, confirm that it uses the exact model and configuration being ordered. Keep a written record of any fit assurance and read the return conditions before relying on it.
Choose the smallest tub that comfortably fits the position you want, even if the yard could hold a bigger one. For broader trade-offs, see our cold-plunge guide, buyer's guide and Titan review (Sponsored by Sun Home Saunas), which we published on September 1, 2026 and which carries the preorder terms and dimensions Sun Home listed then.
Which cold plunge has the longest interior in this comparison?
The Aurelius has the longest published water-area length here at 62.5 inches, compared with the Titan's 58.5 inches and the Siberian Pro's 48 inches, on the makers' pages read November 10, 2026. Those figures don't prove comfort for a particular person. Seat shape, depth, torso length, shoulder width and the intended waterline still need to be considered.
Is a larger outside dimension better for a tall person?
Not necessarily. The 80-inch-long Siberian Pro lists a shorter interior than the 70-inch-long Aurelius. Equipment compartments, decks and construction occupy space outside the basin. Compare the actual water area and intended posture, then separately check whether the external dimensions fit the delivery route and installation site.
Does a stated maximum user height guarantee that I will fit?
No. People who are both 6 feet 6 inches tall can have different torso and leg proportions. Treat a brand's height guidance as an initial filter. Request the current interior drawing, seat geometry and normal waterline, and check return conditions before relying on a fit claim for an expensive order.
Are these prices the total installed cost?
No. The November 10, 2026 figures are displayed equipment prices: $11,999 for the Aurelius, $15,499 for the Siberian Pro without the spa light, and $14,599 on sale against $15,399 regular for the Titan. The 500-use comparison covers equipment differences only. Add applicable taxes, moving, site preparation, electrical work and ongoing care to build an ownership budget for your property, and get the shipping terms in writing.
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