I just saw the current dishwasher is listed on this page of quietest dishwashers under the ”best cleaning” category. https://www.designerappliances.com/blog/your-guide-to-find-the-most-quiet-dishwasher/#thequietestdishwashersin2023

However, it’s one of the loudest of the supposed ”quiet” dishwashers at 45 dB.

I also wonder if some of the noise that seems to be coming through the door is actually coming from behind the toe kick.

I think next time, I will need to get a 40 dB or less model if soundproofing efforts don’t help.

I wanted a model with front controls so I can see at a glance when the cycle will be done without needing a phone app and also either auto open or Crystal Dry to ensure the dishes actually get dry. Choices with that combination of features are limited. So, I ended up with this model that isn’t as quiet as I wanted.

I can only write to my ancient "Optima" Miele. Quiet requires that the toe kick or any auxiliary toe kick retain the rubber piece that connects (acoustically seals) the frame to the floor. Side gaps and top gap have to be near zero.

If cabinets are vibrating then indeed stick-on automotive dampening material may help.

Is your countertop stone or wood? Did you reinforce your floor in your last reno? Vibration there can be dampened by adding underneath structure.

Once upon a time, mechanical engineering magazines had lots of ads for dampening material to be used under metal working machines (such as lathes) feet. If the floor is guilty but not rehabilitateable, then such material may have some value, but I realize that having to move the DW, as well as getting to the DW rear in situ may require some thought about how such a mod can be incorporated.

Zero actual questions? The questions were mentioned an implied.

For example, whether my thoughts on insulation materials (mass loaded vinyl or car stereo shop sound insulation etc. glued to the walls and ceiling of the dishwasher bay) are the best options, whether something should go behind the toe kick to stuff that space to absorb noise, whether putting something on the tile floor under the dishwasher would help absorb noise.

I mentioned it was an open floor plan.

The dishwasher is in an island (actually at the open end side of a peninsula). The rear of the peninsula faces a living area and doubles as a bar height eating area. So, there is much more sound leakage from this type of dishwasher installation than if it was installled into an exterior facing wall.

We just run the dishwasher at night right before going to bed. Don’t hear any noise that way. Try that.

Why does the DW noise bother you so much? It can’t be THAT loud. We have a lower-end Miele and you mostly hear the water swishing around and some clicking. How do you vacuum, run the laundry, the disposal? Those are all much noisier.

The countertop is granite.

The floor is not reinforced. It’s tile installed over concrete slab at ground level.

If it is at the end of a cabinet run, or on an island or peninsula, that can be a problem with hollow spaces acting as echo chambers. If there aren’t the proper side gaskets, or toekick, sound can escape.

You ought to at least upload a video to YouTube. Without any pictures, or videos, this is sounding like a you issue than a DW install issue. Because it is not a DW issue.

There's no way to achieve 0 dB sound level transmission. Closing all gaps around the machine as it fits into the cabinetry -- sides, top, floor -- is reasonably the best that can be done.

Search for “dishwasher soundproofing blanket” and you’ll find specific products made for this.

I think if you line the 5 sides of the hole the DW fits into with sound proofing or acoustical materials it should make a difference. Also plug any holes/gaps were sound might pass through. You are still going to hear water swishing and if you don't load properly, plates shifting. Also make sure that your water supply pipes aren't making the noises.

It does not need to be ”0 dB,” but so many people in these forums post that their dishwashers are so quiet that they can’t even tell whether they are running or not.

My dishwasher rated at 45 dB and I think that would be “good enough” if I was actually getting that, but I think, because of the open end peninsula installation and open floor plan, it will take extra work to even get the noise level down to 45 dB. It’s distractingly loud as it is.

What are suggested materials to line and seal all the gaps around the dishwasher that would not end up causing problems with blocking air intakes and exhausts from the dishwasher or interfering with opening the door?

I can’t think of any sound dampening material for the tile floor under the dishwasher that wouldn’t be an obstacle for sliding the dishwasher in and out.

Euro dishwashers and American dishwashers differ in width dimension. If your cabinets are set for US dimensions, then a 3/8" (vague memory; probably difference between 30 inches and 75 cm) wood shim is needed on one side. The Mieles of my experience screw into the walls on each side, so a snug fit is needed. The shim need not be very deep, front to back.

If the counter is stone and the floor is on concrete, then I wouldn't expect much vibration transmitted via those sides of the cavity. This leaves gaps and sides and maybe back, depending on how it is configured. Quality cabinets use 3/4 side plywood, but only 1/4 often at the (usually wall) back of the cabinet. I'd slap some Evercoat Q-Pads or equivalent onto the back once I fixed the side gaps. Then, if persistent, anti-noise coverings designed for dishwashers may be needed. Be sure that thermal management is not degraded.

I installed a dishwasher in an island and had enough clearance to sound insulate around it. I cut down 2' x 4' fiberglass ceiling tile and glued them to the interior side panels of the cabinets.

Can you describe what’s needed for the shim to properly fit Euro sized dishwashers into a US opening? Is a wood shim going to block noise? Wouldn’t I need something that will block/absorb sound like rubber or foam?

The dishwasher I have is not screwed into the wall. It just rolls in and out.

Maybe I need to get a GE Profile dishwasher next since I think GE is the only US-sized brand that makes very quiet dishwashers.

It is probably easier and cheaper to just get a quieter dishwasher and sell the Miele.

The wood shim blocks noise just like the cabinet sides do.

In the directions below, the inherent assumption is that the cabinet sides are perpendicular to the cabinet faces.

Measure the gap; measure the Miele width. The difference, less a bit for clearance, is the shim thickness. Any clearance values should be in the Miele installation instructions.

Cut the shim from scrap material used for the cabinets, or have the cabinet manufacturer cut one for you (if a custom cabinet set) or find a finish carpenter. You likely want the viewable edge to have a matching finish, although that is up to you.

Length of the shim, top to bottom is from floor to stone countertop.

Depth of shim, front to back, needs to be sufficient to be flush with the cabinet frame and extend far enough so that the Miele mounting screws have meat to go into.

Screw the shim to a cabinet side, taking care to use a length of screw that doesn't penetrate into the cabinet volume, then attache the dishwasher. Mine has three screws, as I recall, on each side. There should be caps that cover the screws and keep water from leaking out.

Important! Do not screw in the dishwasher until it is snug against the stone countertop, leveled in all directions, and properly aligned with the cabinet faces. Whenever my dishwasher has had to be removed, I have spent upwards of an hour doing recursive alignment until satisfied.

Is your dishwasher on wheels? Do you have the installation directions? You may be able to download them or order them from Miele parts dept.

We got a Whirlpool from Lowe’s about 2 months ago, and I never thought I’d love a dishwasher but I love this $600 dishwasher. It fits a ton of dishes and pots and pans, it’s quiet, and it gets things clean. Hopefully it passes the test of time.

Sounds like too much work and expense to do the wood shim that would kind of lock me into this dishwasher, making it difficult to service and isn’t even guaranteed to solve the noise issue.

I think I would want something easy to remove and with sound absorption properties. Maybe a black rubber strip similar to weatherstripping around the dishwasher?

Then, the next time I buy a dishwasher, I will be sure to getting a 40dB or less model.

The point of the screwed-into-place wood shim is to make the space suitable for Euro dishwashers, while still allowing shim removal for use with US dishwashers. I designed my (Tedd Wood cabinets) dishwasher space in both width and depth for this interchangeability.

I will bet a donut against a donut hole that the noise spec for quiet dishwashers has, in the fine print, a requirement that it is installed according to the installation guide, and not loosely in a cavity.

Per https://www.houzz.com/discussions/2265421/miele-sound-ratings and its referenced threads, my Optima noise level is 44 - 45 dB(A).