A spa that hums during the day often goes unnoticed. That same noise, however, quickly becomes an issue in the evening. Do you hear a buzzing sound, feel vibrations in the deck, or hear a continuous whooshing noise as soon as the jets start running?

At Atelier Nordic, we treat noise as a design issue, not an inevitable fact of life. The right approach is to identify the exact source and then address it in the right place, without blocking ventilation or complicating maintenance.

Even though Viskan spas are extremely quiet thanks to their inherent design features, this article will help you understand where the noise comes from and how to reduce it.

A noisy spa doesn’t produce just one sound. It produces several, often overlapping: a motor, air, resonance, and sometimes just a vibrating cover. Before adding foam everywhere, start by isolating each source of noise.

Simple test: Listen to the spa in four different operating modes. Filtration only, heating only (if possible), massage at half power, and massage at full power. Each time, note whether the noise is more low-pitched (vibration) or high-pitched (whooshing, hissing).

Identify the mode, then the source.

Turn off the massage. Is the noise still there?

If so, the issue is likely with the filter pump, a resonating support, or a part that’s making contact. If not, the issue is with the massage pump, the blower, or the jet hydraulics.

• Does the noise change depending on the mode (filtration / massage / bubbles)?
• Are vibrations noticeable on the floor, on the patio, or on a trim piece?
• Does a panel or hatch “slam” when the pump starts up?
• Does the lid vibrate or rattle when it’s closed?
• Does the noise increase when the hot tub is near a wall or a corner?

The filter pump is often the most annoying nuisance, because it happens every day. It can produce a continuous humming sound, which is sometimes amplified by the hot tub’s structure or the concrete slab.

What if the problem were mainly a matter of timing? The first solution is to adjust the cycles. Smarter filtration, scheduled for times when you (or your neighbors) are least likely to be around, changes how the system is perceived without requiring any changes to the equipment. However, avoid setting the cycles too aggressively: water that isn’t filtered properly puts a strain on the system, causes it to clog faster, and may end up making more noise.

Another simple question: Where is the hot tub located? An outdoor spa placed near a corner of the walls reflects sound back toward your patio like a reflector. Moving it a few dozen centimeters away, or breaking the direct line of sight with a screen (trellis, dense foliage, low wall) often helps more than you might think.

A pump may be in good working order but still make a loud noise because the mounting surface acts as a sound box. An uneven slab, poorly distributed support points, or a deck on joists that is too flexible can transmit vibrations.

The solution is mechanical: a perfectly level support surface, followed by decoupling. In practice, we use vibration-damping pads suited to the load, or an acoustic decoupling mat under the base when the configuration allows it. The goal is not to “soften” the spa, but to break the vibration path between the machine and the structure.

The support either amplifies… or dampens the vibrations.

When you activate the jets, the noise changes in character. It may become deeper, with a vibration that spreads, or more “choppy,” a sign that the hydraulic system is not operating in a stable range.

Have you checked the water level? If it’s too low, the suction line may draw in air and create a cavitation noise, accompanied by a crackling sensation and a drop in performance. Also check that the valves are fully open and that not all the jets are closed: a pump working against too many restrictions can become noisier.

Mechanical noise should be addressed at the source.

That’s a good idea… as long as it doesn’t block the equipment. On some spas, a soundproof enclosure around the equipment unit can reduce perceived noise, especially if the noise is airborne (propagating through the air) rather than structural (propagating through the ground). The classic mistake is to enclose the pump without allowing air circulation: heat builds up, and reliability decreases.

The right approach: sound-absorbing materials on the inside, massing on the outside, and controlled airflow. At Atelier Nordic, our engineering department also considers maintenance needs : access to fittings, the pump, fasteners, and the drain. An unnecessarily complex enclosure often ends up being dismantled… and the noise returns.

The blower produces a higher-pitched noise that carries more easily through a garden than the simple hum of a pump. The jets themselves may whistle if there is too much air, if certain nozzles are partially clogged, or if the air-water mixture is set to maximum.

So, what can you do without taking everything apart? There are two simple and effective steps: reduce airflow when you don’t need it, and reserve “bubble” modes for times when the environment is more forgiving. In the evening, the whoosh is often the first noise heard beyond your property.

What if you moved the water source farther away? If your installation and spa model allow it, choosing a remote utility room is a smart approach: you move the overhead water source farther away, control the acoustics, and enhance comfort around the pool. In a professional wellness space design, this decision must be made early on, as it affects the utility systems, the access hatch, and the overall insulation.

Many spa noises do not come from the spa itself. They come from the surrounding area. A wooden deck built on a lightweight frame can act like a membrane and amplify low frequencies. A slab that is too thin, or that hasn’t been fully decoupled, can transmit vibrations to a wall, which then redistributes them.

In these cases, adding sound-absorbing material to the spa makes almost no difference. You need to address the transmission path: reinforce the support area, add decoupling, or ensure the surface is level. A flat, stable, and properly sized support surface remains the foundation, even for a perfectly insulated spa.

And what about the lid? It could be the culprit. A lid that’s not secured properly, or a strap flapping in the wind, creates a very irritating intermittent noise. The wind is the number one enemy.

Check the perimeter support, the condition of the hinges, and the contact points. A simple adjustment may be all it takes to eliminate resonance.

Noise has become a public health issue. According to theEuropean Environment Agency, more than 20% of Europeans are reportedly exposed to levels of traffic noise considered harmful (END thresholds). In Switzerland, the FOEN reports that approximately 740,000 people are exposed to road traffic noise deemed harmful or bothersome (sonBASE, 2021 calculations). This situation is changing residents’ expectations, especially at night.

In practical terms, what happens most often in the field? As for mistakes, we see five that come up repeatedly:

• placing the hot tub on a patio that is too soft,
• Place the spa in a prominent corner,
• sealing off the equipment without ventilation,
• Overloading the absorbent material without maintenance access
• compensate for noise by increasing the jet power.

For evening use, keep it practical: avoid the most airy modes (bubbles), reduce the air injection, and set the filtration to more neutral settings. If you’re unsure whether to choose an indoor spa and an outdoor installation, the building’s acoustics and wall treatment become a separate issue that must be addressed from the design phase onward.

Want to get an objective view of your situation? The ISO 3744:2025 standard describes an “engineering” method for determining the sound power of a source based on sound pressure measurements, which is useful for comparing equipment under controlled conditions.

Without going that far, a structured approach (identifying the mode, the transmission, and then the corrective action) resolves the majority of cases.

If your hot tub is already bothering you, your neighbors may be hearing it, too. Tell us what you hear and when: at Atelier Nordic, we can guide you toward the simplest solution—or a more sophisticated approach when the layout calls for it.