Motion transfer confusion re: latex vs pocket coil

Mattress Talk General Mattresses Questions
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I built a latex mattress a few years ago after extensive research including a lot on this site. I’m very happy with most aspects of it. I have it on a thick coir pad on top of a Floyd platform. The mattress itself is medium Talalay over firm Talalay over extra firm Dunlop. This setup is certainly better for motion transfer than most mattresses in the world, but it’s not perfect.

I’m unfortunately a light sleeper and my partner is a very active deep sleeper. We recently stayed at the Andaz hotel in Tokyo and I noticed that the bed had the best motion isolation I have ever encountered. It was like sleeping alone. Now I want one, or something like it.

I went as far as taking the sheets off to see what the mattress was. I was expecting something super high end, but it was just a Simmons Beautyrest. I gathered from what I could google that it was a relatively high end (for Simmons) pocket coil mattress. I found this googling parts of the model number, but no matches on the whole thing of course: Beautyrest Premium Extra Hard(シングル)の通販 / マスターウォール. It was on top of a fairly sturdy platform.

I’m confused now, because I always thought that a pocket coil mattress, while better than a plain inner spring, would have significantly more motion transfer than a foam mattress. I know that memory foam is better than latex, but I hate everything else about memory foam so that’s not an option. I’ve gone down the rabbit hole a bit looking at the Texas Pocket Springs bases that people have put various comfort layers on, but I also find some people saying motion isolation is great and others finding it terrible when discussing those builds.

What am I missing? Does it come down to encasement choices and the stability of the platform? Is it really just differences in personal tolerance? Different kinds of motion? What is the discrepancy here? With almost everything I’d consider buying online or in DIY pieces, it’s tough to just try things out.

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Latex mattresses are often great for motion isolation, but Talalay latex in particular is naturally springy and tends to return energy rather than dissipate it. This create ssubtle waves across the surface that light sleepers often notice. In your setup, the presence of a coir pad adds additional bounce, because coir acts a bit like a natural box spring. The Floyd platform looks really solid, but you have to check if it is flexing slightly compared to the extremely rigid foundations used in hotels, which further increases the amount of motion that travels across the bed. Looking at that Floyd, you would not think it would add to the motion you are getting, but you want to place your phone under the bed and record while getting into the bed. If you see some flexing, that could be a source of the problem.

The Simmons Beautyrest you slept on at the Andaz performs differently because hotel pocket coil systems are engineered for damping rather than bounce. The coils are individually wrapped in frictiony fabric that reduces sideways energy, and the mattresses often include dense polyfoam layers and stabilizing pads above the coil system that absorb movement before it reaches the surface. Most Simmons BeautyRest mattresses also incorporate viscoelastic memoryfoam in their comfort layers, where you would notice minimal movement. Additionally, this creates a quieter, more isolated feel than your typical latex stack, even though many people assume foam always isolates motion better than springs. The use of the word foam, can in and of itself be a point of contention. Some folks who have not done much research or never had to do any when seeking a mattress, just think, foam is foam. Obviously, we know that all foams are not the same and do not exhibit the same characteristics.

People sometimes report wildly different results with pocket coil systems like Texas Pocket Springs because performance depends on many interacting factors. Coil height, coil gauge, coil density, encasement materials, comfort layers, and the rigidity of the foundation all matter. A pocket coil system with Dunlop latex and a rigid base can isolate motion very well. The same coil system with Talalay latex and a flexible base can feel quite lively. These interactions explain the apparent discrepancy between what you expected and what you experienced at the Andaz.

I recently stayed at the Andaz in San Diego, and it was a horrible sleeping experience. We both woke up with sore backs, although, motion isolation was pretty good, the mattress was horrible for supporting our bodies. Granted, we are used to a very firm mattress. One thing that I will recognize is that when folks are not completely happy with their mattress at home, almost anything else seems to be better. In our case it is the opposite most of the time.

Hopefully this helps. I am certain there may be others who have a different take on all of this.

Maverick

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Thanks for the info. The point about my observer bias is one I’ve worried about. Like I said I’m pretty happy with my home mattress, but the previous two weeks in Japan were mostly pretty typical hotel beds. Except for the one traditional place where we slept on Tatami with futons–which I actually loved–they were all pretty plush mattresses until this one. So maybe I was primed to love this one.

One more question: does what you say about hotel pocket coil systems mean I wouldn’t expect the same features from something like the Texas Pocket Springs systems? My inclination is to avoid the big manufacturers but maybe that’s wrongheaded in this case.

Thanks again for all the context.

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You cannot really assess the comfort after a brief hotel stay. A hybrid mattress is the best.

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I’m sure Maverick will have more to say here but I’d just explain to @PSS what you’ve after. If they’ve got it in stock, they’ll let you know. If not, they’ll have ideas for achieving the dampened feel.

NikkiTMU

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Thanks, I may give that route a try! What I’m struggling with most is whether the pocket coils are even the right path to go down, versus sticking with all latex foam. I see that the pocket coils are surprisingly inexpensive but I’d still feel guilty about buying such a large slab of material and having to throw it out if it doesn’t work for me.

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@Maverick is 100% right pointing out all the different factors that change the feel of the different components of a mattress. Often times hotels like to use mattresses with very thick comfort layers, almost to the point that the pocket coils have no impact on the feel.
To get the best motion isolation on a pocket coil mattress, LESS is best. Meaning if you can find a mattress or build one yourself with just a single layer above the coils. It basically there simply to insulate you from the feeling the top convolutions of the coils. The beauty of a pocketed coil is you get motion isolation and still have that alive feeling below you vs a foam our latex where you may have the isolation but it can feel dead under you. We like to say Foams you sleep in pocket coils you sleep on.
Hopefully I made some sense here :grinning_face:

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Motion transfer can be tricky, as every layer can potentially be the issue. The Floyd bed is potentially a part of the problem, as metal legs can be resonant and have a side to side vibration. The panels can flex slightly, pulling material layers towards that point (like a tugging motion). Look under the bed while someone gets in and changes position a few times, you should be able to see and/or feel the movement. An uneven floor, where the center support is not level, can also cause motion. Talalay latex is “bouncier” than Dunlop, but in my experience, this is not a motion issue unless you have a ton of it (like more than 3" in one layer) over a spring, or are layering a firmer material over a softer. Pocket coils vary tremendously, but excessive motion is usually because of a scrim layer creating surface tension (vs. an open cylinder pocketed coil), and essentially joining the springs (this surface tension can also be created by glueing layers to the coil unit). The encasement being a woven fabric, or a knit with a woven backing, or non-woven liner, can make a drum head effect on the surface, adding vibration. The density of the mattress is also very important. Basically the heavier the mattress the more it damps vibration (all things being equal, firmer mattresses move less, but can vibrate more if they aren’t heavy/dense). I would say the base matters the most, as long as you take into account the other things. The mattress pad (and the sheet to a much lesser degree) can contribute motion too. :slight_smile:

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