The Evermore Standard: Why We Engineer for Longevity

The Evermore Standard is what AlumiTubs builds to: a hot tub that can be worked on, that changes as your life does, that we still supply parts for decades after it ships, and that holds nothing inside it that cold or bacteria can reach. It is not a badge on the box. It is the set of engineering decisions that let the first tubs, built in 2001, still be in use, and it is the reason a tub bought once can be kept for life. Here is what it means, in the order it matters.

1. It can be worked on

Nothing on an AlumiTub sits behind sealed panels or packed foam. The heater, pump, control board and filtration are fully concealed in the integrated cedar steps against the tub, detachable, pre-plumbed and reachable by hand. The firebox is bolted in. The cedar is held on by stainless bands. Every one of those is a component fastened to the aluminum structure rather than a part of it, so any one of them can be reached, inspected and replaced without dismantling the tub or calling anyone out.

That is the opposite of how most spas are made, where the working parts are buried in a cabinet and reaching a failed component means a service visit and a decision about whether the whole thing is worth repairing. A tub that can be worked on is a tub that gets repaired rather than replaced, and it is the first thing the standard asks for because everything else depends on it.

2. It changes with you

The heating system is modular, not integral. A Wood Fired built with the optional compatibility ports can take the Electric heating and filtration kit years later, so the tub you bought for an off-grid cabin becomes an Electric when the power arrives, or a Hybrid that runs both. The 120V filtration add-on converts to 240V heating with the same equipment. Three configurations already exist for three kinds of life, wood for the wild, electric for daily use, both for changing circumstances, with an optional 5.5 kW element for tubs that rely on electric heat alone in very cold places, and the tub moves between them without being rebuilt.

It also moves, full stop. At 200 to 300 lbs empty and 38 inches on its side, it rolls through a gate and travels in a pickup, so it goes with you when the property changes.

3. Parts, as proof

We still supply parts for tubs built two decades ago: filters, anodes, chimney components, bands, insulation, cedar boards, heater and pump parts. That is not a promise; it is the record of a company that has kept its earliest tubs running rather than designing them to expire. A 25 year structural warranty on the aluminum structure is what the warranty page says; that parts record is what makes it believable.

4. Nothing inside that cold or bacteria can reach

An AlumiTub has no banks of jets, no internal plumbing runs and no filter chamber inside the vessel; on tubs with filtration, one gentle jet returns water from the equipment outside it. There is nothing that holds water where a drain and rinse cannot reach it. That single decision does two jobs.

For hygiene, it means there is nowhere for biofilm to establish, which is why the water needs far less sanitizer than an acrylic spa and why no UV or ozone is fitted. For freezing, it means the vessel itself holds no trapped water. Drained and left empty, it has nothing to freeze, which is why an AlumiTub can sit through a winter at an unattended cabin in a way that an all-wood tub, which must stay full to stay sealed, cannot. The equipment on an Electric or Hybrid sits outside the vessel in the steps, drained before a long outage or a season, and the manual sets out how.

What the standard does not claim is that a tub full of water can freeze solid without harm. It cannot, no tub can, and a freeze with water inside is not a warranty matter. On an Electric or Hybrid, freeze protection runs for as long as there is power; plan for a long outage separately, and on a Hybrid the firebox covers it.

What is already engineered in

• Corrosion resistance and a long-life finish. A riveted 5052 marine-grade aluminum structure with built-in protection applied as part of manufacturing, stainless bands and components, and magnesium anodes on every tub with filtration. Kept within its water care ranges, the aluminum does not corrode.
• Coastal environments. The structure is the metal boat hulls are made from. Ocean fills are changed every five to seven days and rinsed between, and a titanium heating coil is specified at the time of order for Electric and Hybrid tubs on sea water.
• Long periods left empty. No staves to dry out and nothing that has to swell back to watertight.
• Cedar over decades. The cedar is banded onto the structure, not part of the vessel. A board can be replaced; the tub does not depend on it.
• A structure that flexes rather than cracks. Riveted lap joints move with the panel through thousands of fill, drain, heat and cold cycles, where a weld in aluminum leaves a softened line for a crack to follow. The Wood Fired has been tested heating in ambient conditions of minus 44°C (minus 47°F).
• Drainage. A drain valve is standard on every tub. The Drain Kit routes the water where you want it.
• Tolerating a mistake. Built-in protection at the aluminum surface means the tub is built to handle an error in water care, not to depend on perfect maintenance. What it does not tolerate is the wrong product: chlorine, salt chlorine generators, and copper or silver treatments stay out.

What care still has to do

Engineering carries most of the load; three things are shared with the owner. Soft water pulls at any metal, so calcium hardness is held at 150 to 250 ppm, and The Purifier and the Balancers exist for that. pH sits at 7.4 to 7.8 and bromine at 2 to 3 ppm, never chlorine. And a tub left filled into a freeze is drained first. Everything else the standard handles. The Water Care Academy walks through the routine, and Check my water tells you what to adjust from your readings.

Aluminum's thermal conductivity is real, and it is part of why the submerged firebox heats water so directly. It is not a claim that the tub heats faster than a stated figure; the heat-up times we publish are the measured ones.

Why we build this way

We build for the long version of a life. A tub that can be worked on, that changes with you, and that we can still supply parts for in twenty years is worth more to the person who owns it than one that looks perfect and cannot be opened. Buy the right thing the first time, keep it for life.

Laura Andersen, Managing Director and Co-Owner, AlumiTubs

The Evermore Standard applies to every AlumiTub: the Wood Fired, the Electric and the Hybrid. How the materials were chosen is in why an aluminum structure and every hot tub material compared; the figures behind it are on the specifications page.

Common questions

What is the Evermore Standard?

AlumiTubs' own standard for longevity: a tub that can be worked on by hand, changes heating system without being rebuilt, is supported with parts decades after it ships, and holds no trapped water inside the vessel. It describes the engineering behind the 25 year structural warranty rather than a separate certification.

Can a hot tub pump or heater be replaced without replacing the tub?

On an AlumiTub, yes. The heater, pump, board and filtration are a detachable unit in the cedar steps outside the vessel, bolted and plumbed rather than built in, so each part is reached and replaced by hand. A Wood Fired built with compatibility ports can take the whole Electric kit years later.

Is an aluminum hot tub freeze-proof?

No hot tub is freeze-proof with water in it, and a freeze with water inside is not covered by warranty. What the design gives is a vessel with no internal plumbing runs, banks of jets or filter chamber, so drained and left empty it has nothing to freeze. Electric and Hybrid freeze protection runs while there is power; the external equipment is drained before a long outage or a season.

Why does an AlumiTub need less sanitizer than an acrylic spa?

Because there is nowhere inside it for biofilm to establish: no banks of jets, no internal plumbing runs, no filter chamber. Water sits in a smooth aluminum vessel, everything it touches is reachable, and a drain and rinse resets it. Bromine at 2 to 3 ppm is the whole sanitizer requirement, and no UV or ozone is fitted.