The cheapest honest way to find out whether you will actually do this

What you are actually buying

The wall is not tarpaulin. It is drop-stitch fabric: two sheets of PVC joined by tens of thousands of 20-millimetre vertical threads, so that at 0.5 bar the wall stands rigid and full of air. That air is also the insulation, worth roughly a third of the 40 millimetres of polyurethane in our permanent shells. The consequence is a bigger heat load: a covered 320-litre portable in Jakarta holds at about 610 watts, against 449 watts for a terrazzo tub of the same volume.

A powder-coated steel tube frame holds the rim so it cannot fold inward when somebody leans on it. Without a frame this style of tub loses its shape within months and the front wall bows outward permanently.

Why we print two to four years on the product page

Three-ply PVC ages from three causes, none of them avoidable. Ultraviolet embrittles the outer layer, repeated folding on the same line thins the fabric at the crease, and the zip and air valve are moving parts that wear out first. In our own service records, a portable used daily and kept out of the sun lasts three to four years; one left open on a rooftop lasts two. That figure belongs on the product page rather than in the small print of a warranty card, because buyers compare these against terrazzo without realising the two are not in the same life bracket at all.

That table exists to make the annual figure visible. A portable tub is not cheap if you are genuinely going to use one for a decade. What it buys is speed of decision, not lifetime cost. Every shell is compared side by side on the pricing page.

Twelve minutes to set up, and how to fold it without killing it

1. Lay out the 8-millimetre foam mat that comes in the box. It is not for comfort; it stops gravel pressing into the floor of the tub for months on end.
2. Fit the six frame tubes and lock the twist catches at the four corners.
3. Inflate to 0.5 bar with the supplied pump. The little gauge is accurate, and over-inflating to 0.8 bar is the most common way these fail.
4. Connect the 32-millimetre barbs to the chiller with quick couplers, open the valves and fill.
5. When packing away, dry it thoroughly for four hours and fold along different lines each time. Folding on the same creases is the fastest way to wear it out.

The sequence that works best

Our happiest portable customers follow the same order. The first two months run on block ice alone, with no chiller, purely to prove the habit exists. In Jakarta that is 18 to 25 kilograms of ice a session, roughly Rp 45,000 to 70,000 a day. If you are still getting in five times a week in month three, then buy an ice bath chiller — and that chiller carries over when you eventually move to a permanent shell, because the only thing you throw away is the tub.

To size the unit, put the volume and your city into the chiller calculator and select a tub without full insulation. A portable always lands one PK step above an insulated shell of the same volume, which is the hidden cost of an air-filled wall.

Three things we change before we sell one

• A different air valve. The push-turn nylon valves supplied by most factories begin to seep after roughly two hundred cycles. We fit a polyacetal valve with a silicone seal and put a spare in the bag.
• Chiller barbs fitted during manufacture, not drilled in afterwards. A hole cut into a finished tub is almost always its first leak, because drop-stitch fabric keeps moving around it. We order the tubs with layered reinforcement at both barb positions from the start.
• A rebuilt cover. Stock covers are thin coated tarpaulin that barely slows heat at all. Ours is 40-millimetre closed-cell foam, worth about 150 watts of heat load — on a thinly insulated tub that is the difference between a 1 PK chiller and a 1.5 PK one.

Those three changes add about Rp 1.1 million to the price, which is why our portable is not the cheapest in the market. We write it down so you can compare like with like when you see a lower number elsewhere.