There are two possible reasons you would want to look into how to soundproof a loud hot tub motor. You are either annoyed by the neighbor’s hot tub sound in the middle of the night or you are simply looking to reduce the noise of your own hot tub and be a good neighbor.
Here is how you could soundproof your loud hot tub under 10 minutes.
Try adding foam, or anything else in between the motor base and the floor. Please do not insulate around the motor. What you want is to eliminate all vibration between the pump and the cabinet.
The pump itself is not very noisy. Additionally, if possible, you might be able to use wire or strings to actually raise the pump from its mount, and suspend it in the air.
If this doesn’t work, there are a few other suggestions that you could try, so keep reading.
- Plywood Under The Tub
- Dynamat Soundproofing
- Acoustic Panels Soundproof Studio Foam
- Source, Path, Receiver Model Approach
- More Things To Check
- Consider Turning The Pump Off In The Evening
- Troubleshoot The Sound. Maybe You Need To Replace Parts
Plywood Under The Tub
People have had surprising luck by simply taking a sheet of exterior-grade plywood and placing it under the tub. They put the spa back down, and they were all very excited that the sound transmission problem was gone. It also seemed to do great with tying any loose deck boards together. Additionally, it closed off the air spaces between the deck boards that can act as amplifiers: Think of a “sound hole” on an acoustic guitar.
And this is a great approach since having a cheap price of a sheet of ply, some free time on your end, some wood sealer, and a tub refill, you could sure give it a try. And the big benefit here is, if it doesn’t work for this specific reason, know that you haven’t wasted anything. Because you really want a rock-solid surface if you want to go ahead and put down something resilient.
If you don’t want to bother getting it from a local store, I found this on Amazon for you.
This is the best choice that will for sure reduce the noise. It is an automotive sound killing material. They sell this for custom audio and flooring but it helped to solve hot tub noise issues as well.
Here is how it looks when you wrap your car door from the inside:
It’s called Dynamat, and you can check its price on Amazon. Try installing it on the backside of the panels if they are what you think is causing the vibration and/or loud noise.
You can also wrap the inside of the hot tub cabinet and even your enclosure box from the inside. Works really well!
Acoustic Panels Soundproof Studio Foam
UPDATE: [August 2020]
I found another great thing for you to use if you are having issues with a loud hot tub. These are acoustic foam panels that are usually used in a studio, but depending on where your sound is coming from, and you have a bit more room to fit the foam and not just the Dynamat, you can go for it and give it a try.
If this good enough to soundproof the whole studio, it will for sure soundproof your hot tub.
- u【Eco-friendly and Safety】Made of high quality environmentally polyurethane foam, these studio foam are durable and effective, no health risks, safe to use.
- u【Noise Absorbing】Our sound foam panels can dampen and diffuse mid to low frequency sound waves inside of a room, to minimize interference, increases increasing sound clarity.
- These soundproofing foam panels come with 24 pack in the package, each tile is 1 square foot of 1 inch thick acoustic wedge, 12 pack covers an area of 12 square feet.
- u【Easy to Install】These studio sound absorbing panels can be used as acoustic cover for walls, ceilings and doors, just easily attach it with staples, nails, screws, tacks or glue.
- u【Widely Usage】Our sound dampening foam panels are great for recording studios, vocal booths, control rooms, also ideal for home theaters, professional movie theaters, concert halls and more.
Source, Path, Receiver Model Approach
Here is another way for you to potentially solve your issue. The way this approach works is the following.
- First, at the source, try lifting the pump of the slab. Then lay a vibration pad right underneath the pump.
- Next, address the path of the noise. While allowing breathing room, get a box enclosure without a lid. This is a really nice box you can get from Amazon. Keep in mind that the heater or pump needs a vent. Then go and make a moderate size vent allowing just enough airflow. Then face the vent away from your home. For the inside, the enclosure uses Mass Loaded Vinyl (MLV), absorbent mat and acoustical caulking. Just to help you make it all the way to the end, I found the mat for you on Amazon as well. Make sure that the open end of the enclosure faces the slab. Finally, along the edges where the enclosure meets the slab, please glue strips of the absorbent mat to prevent vibration.
- Lastly, let us soundproof the receiver. If you do not have a wall, build one as soon as possible. Preferably, make the wall as tall, if not taller than your home. You can also begin to plant trees and shrubs so they can absorb the sound. If it is a case of a particular room that is loud, then address soundproofing the room itself.
All these suggestions are general and meant to be used by most “do it yourselfers.”
More Things To Check
I found another case that was successful. Sometimes it’s a combination of different things that are causing the noise and not the motor itself. Check if any of the following can apply to your problem:
- The suction pipe was quite rigid, and it was supported by a wooden block that was attached to the frame of the hot tub next to a side panel. The side panel then vibrated like an acoustic guitar body amplifies a string pluck. The pipe was replaced with a flex pipe and they removed the block.
- Then the discharge pipe was also rigid, connected directly to the heater, which was rigidly plumbed to the filter body. The pipe was then replaced with flex.
- Even though having a plywood base can be a good thing, in this particular instance, the base was causing the issue. The pump was screwed down to a plywood base and making the plywood vibrate like a drumhead. A couple of rubber mounts installed fixed the issue.
- The power cable was jammed up against the equipment door and pump, passing the noise as the suction pipe support did, so zip ties were used to isolate its contact points to the control box only.
- The bonding wires (those are the bare wires running from the equipment to the control box) were coming in direct contact with the pump motor and rattling. The wires were bent clear of any contact except their attachment points.
After solving these problems, it seemed like a good idea to go one step further and add a weather stripping (single side adhesive) to the contact points right between the equipment door and the hot tub. This will additionally secure the tub against the noise.
Consider Turning The Pump Off In The Evening
Let’s face it, you wouldn’t have any problems if the pump weren’t running at all. While this doesn’t completely solve your problem, I still think it is worth considering again because generally, people don’t want to compromise for the sake of maintaining great relationships with their neighbors. What you can do is to put a timer on so your pump wouldn’t run during the night.
Troubleshoot The Sound. Maybe You Need To Replace Parts
A general rule of thumb is that the higher quality tubs are the quieter they get. This means that you can certainly expect different noises much sooner from a cheaper hot tub than a higher quality hot tub.
A lot of this is related to the type and amount of insulation used. If you think noise will become a worry for you, ensure you purchase a unit that has just the right amount of insulation surrounding the motor.
The following subheadings are all related to sound issues and Dynamat from the beginning of this article is highly effective in suppressing loud, unwanted sounds and irritating noises.
I already shared the link to where you can get it on Amazon. Here it is again so you don’t have to scroll up there.
I Can Hear A Clicking Sound
A hot tub that makes a clicking noise might, in fact, be working just fine. However, when the pump doesn’t turn on top speed, and everything you hear is clicking, or the heater isn’t heating and you hear a clicking sound, they might be coming from hot relays or contactors. If you attempt to find the offending part, do this attentively, together with the power turned away, as a shock hazard could exist.
My Hot Tub is Squealing
A spa or hot tub that makes a squealing noise will usually have a pump that’s nearing the end of a life span. The motor bearings specifically, finally wear out after quite a few years, and will start to shriek like a banshee!
The sound becomes increasingly louder over time, and if you don’t fix it, it will lead to motor failure. To confirm that the noise is really bad bearings, close all valves and remove the motor from the wet end.
Turn on electricity for a few seconds and if it still makes the noise, then for sure you want to do a complete motor rebuild from a local motor shop or maybe even replace your motor, or buy a whole new pump.
Softer squeals may be heard coming from open-air intake jets or any spa ozonators. They create a minimal squeal when they are operating which shouldn’t be a problem.
A hot tub pump motor may make a humming sound, that is really coming from the motor capacitor itself. Sometimes the humming noise would precede the popping of the circuit breaker.
Vibrations can be another common source of a spa humming noise coming either from the sub-floor or equipment housed beneath the hot tub. As suggested above, make sure that all equipment is tightly secured, or strapped with zip lines if needed. Rubber patio squares can also be used to reduce the noise.
What’s Buzzing In My Hot Tub
Sometimes the buzzing sound can resemble the squealing or humming sound, and can even be a variation on the clicking sound.
Most of the time the buzzing is caused by a pump or blower motor that is having a hard time starting. In other cases it is a heater contactor or relay that’s causing the buzzing noise.
It is also possible that some ozonators can cause this squeal on them. To be 100% sure about what’s making all that noise, first, go and check your control panel for any error codes. After all, stick your head under there with a flashlight and listen for the noise. It could really be something as simple as a cord leaned against the body.