Due diligence on pocket coil mattresses

Hi Phoenix & all!

As we progress, I’m doing my due diligence on pocket coil systems. I’m specifically reasearching the Berkeley Ergonomics beds, but generally other pocket coils as well.

A have a number of questions that I’m hoping you can shed some light on regarding quality. I’ve learned that the Berkeley Ergonomics “Willow” or “Alpine” model is as follows:

  • 1530 pockets coils for a king- they are honeycombed like the attached photo.
  • Since it’s honeycombed, some are taller & others shorter. I believe the taller rows are ~13.75 gauge & the shorter rows are ~16.75 gauge. (2.1mm & 1.4mm since they are German coils)
  • Coil tensile strength is 1900-2100N/mm2 (not sure what this means) :wink:
  • then they are 2" of latex on top and a wool cover.

Primarily I wondered about the following:-the durability of pocket coils in general, but specifically with the stats above.

  • the coil count listed above for a king
  • if honeycombed multilevel structure adds to the strength or durability
  • if adding a topper of wool & latex would extended the life of this set- by buffering the coils a bit more than just the 2" of latex or if it doesnt matter at all.

And then lastly in my digging, I’ve read various conflicting things about foundations for this type of bed. Whether a solid wood foundation is best or whether a flexible slat foundation is best. One source said that coil beds like this should NOT be paired with a flexible slat foundation. Sovn of course tells you that they were built to go together. So, just wondering thoughts on that too.

Getting there & learning tons! :slight_smile:

Here’s another side cut of the “Willow” from Berkeley Ergo.

The coil system + 2" of soft, medium, or firm talalay latex based on preference.

BTW- the gauges I gave you are for the C&D models- firmer than the A&B option.

Hi Sleepless,

These coils aren’t honeycombed but laid in parallel lines. Honecombed coils are when each coils is placed in between the coils in the row beside them.

The thinner gauge coils would almost certainly be the taller ones as the goal with coil systems is to have a variable spring rate with the softer springs (or part of the springs) compressing first and then transitioning into firmer coils (or firmer compression) after the initial compression. This is to increase the ability of the top part of the coil system to take on a body shape without losing the ability of the firmer coils (or deeper compression) to provide good support.

The higher coil count would provide the equivalent of better “point elasticity” meaning that smaller areas can compress without afftecting the area around it. Higher coil counts are usually an indication of either a honecomb layout (which can fit more coils into a given area with less “gaps” between the coils) or a smaller coil diameter. In this case the coils would be a smaller diameter since they are not honeycombed.

Other factors in terms of how a coil performs would be the number of turns in the coil, the type of steel used, any pre-compression in the coils, zoning, coil height, coil travel, spring rate, fabric used, and many other factors. The manufacturing of springs is a complicated blend of materials and metallurgical science and the math involved in spring performance.

These are clearly high quality coil systems … but how suitable they are for each individual depends on how well they interact with the layers above them to produce pressure relief and alignment. Beyond this it becomes a matter of durability and price. Since most steel coils outside of the cheap imports are usually quite durable … the biggest issue really is how the innerspring interacts with the layers above and below it and with the person who sleeps on it.

A boxspring is usually a good idea with innerspring mattresses if for no other reason than to act as a shock absorber. Innersprings can “take a set” beyond a certain pressure or with sudden shocks and the boxspring can help offset plastic deformation or compression set in an innerspring. In some innerspring mattresses … the boxspring is also part of the designed performance of the mattress.

The coil count is high and the gauge of the shorter springs is also strong. I would expect that this would last a very long time. Pocket coils in general will not last as long as a comparable spring in other designs (which are attached to each other and “share the load” more) because they compress more individually without affecting their neighboring springs. Having said that though, there are so many variables involved that it would really be impossible to generalize. Good quality pocket coils in most circumstances will be quite durable and suitable for most people. For very heavy people it would be more important to pay attention to coil gauge, number of turns, number of coils, and other factors which translate into the amount of “working steel” in a pocket coil innerspring.

Honeycombed (which this isn’t) would add to the number of coils which would improve durability (all other factors being equal). the multilevel structure would have less of an effect on durability as it would on comfort and the ability of the innerspring to be “soft on top” and “supportive underneath”.

This would do more to change the feel of the pocket coil and the latex and the overall mattress than it would add to its life. It would reduce the ability of the latex and to a much smaller degree the coils to act individually under pressure and “firm up” the mattress to some degree depending on the thickness and density of the wool and how much it was compressed and how it was quilted. It would not really have any effect on the durability of the coils.

In the end … there are too many factors in innerspring design to really take all of them into account and/or make accurate predictions and if they are good quality, then they are not normally the weak link in a mattress anyway. Like everything else in mattresses … the most important part of every component is how well it helps each individual with pressure relief, how well it contributes to spinal alignment and the most accurate way to determine this is to actually lie on the mattress. Beyond this, preferences, durability (or likely weak links), and the benefits of the component versus its cost are the most important considerations.


Thank you Phoenix, this is helpful!

Sovn & Berkeley both do state that their coils are honeycombed & it does look like they are in person. I’m thinking maybe this photo is just not clear from the angle. Here’s what their site says…

The right support with little motion
Our carbon steel, German coils are hand-assembled in a honey-comb layout. They give “head-to-toe” support, yet allow enough give to reduce pressure at the high contact points. Because of our unique honey-comb design, our coils move independently, responding to your body contour and weight, but only exactly where you need it.

For the box spring-- does that mean that the flexible slat system would be good afterall? Since it would absorb some of the shock for the springs- as opposed to a solid wood non-flex foundation?

In the store- the “C” model seems like a good fit b/c the coils are firmer than those in the A/B model & with the firmer coils in the C/D model- you then determine either a softer 2" latex top, or firmer. I liked the firmer coils with the softer latex top- the C b/c it seemed to provide good alignment and conformity, but the 2" of 25ILD talalay latex on gave it just enough cush on top. But, the core was still firm enough to keep alignment while on my stomach…in the store anyway. Need to go back again.

They do also have the all latex mattress, but now that I’ve slept on latex and couldnt seem to adjust, I’m just slightly hesitant about that b/c I just seemed to have trouble with the feeling of ALL latex for some reason. The latex over coils seems like maybe it gives the benefit of latex, but still a bit more traditional feel b/c of the coils.

I think the all latex option might be more durability in the long run, but again, if I could get a nice happy 10 years out of a good coil system + 2" latex, I would be MORE than thrilled!!!

Hi Sleepless,

The first picture sure didn’t look honeycombed but the second one does and I took a closer look at the BE site and you are right, the shorter coils (darker) are nested in between the taller coils and it is a honeycomb pattern. The pictures were a little misleading and I was not so observant :). That’s good news.

I’d be a little hesitant to put a pocket coil mattress on a slatted frame. Roewa … the manufacturer of the slatted base … hedges a bit on this but doesn’t normally recommend it either (see the last paragraph here). There certainly are some innerspring mattresses that are designed to work on a flat slatted, semi-flex or solid base and I would tend to go with the recommendations of the manufacturer rather than the store that sold them.

You have my curiosity up now though and I plan to phone a few of the BE outlets and BE itself to see what they say and if they are consistent … particularly since the manufacturer of the slatted base they are using doesn’t really recommend it either. Normally a tension adjustable base will do better and is designed to be underneath a foam core mattress.

I think this is a very good choice for those who are more comfortable with the feel of an innerspring vs an all latex core and with latex in the comfort layers and a good quality innerspring … particularly a good pocket coil or offset coil … it would make a high quality and durable mattress.

With latex in the comfort layers … you should certainly have no problem with getting a good 10 years (and probably more) out of this construction.


I too am very interested in the Berkeley Ergonomics mattresses. They are the only pocketed coil mattresses I have found other than very expensive, handmade, imported ones (Hastens, Vi-Spring) and the Big S brands. I first saw them on the internet at DesignSleep in Ohio. I then found them in a few other locations including SOVN in Dallas. Dallas is only a few hours’ drive away so that seemed like a possibility. Unfortunately, their prices are significantly higher than every other BE outlet. So i have been watching this thread with interest. I have slept on latex for years and find that it is not providing enough lower back support anymore. The BE mattresses look like a wonderful option. However, I am hesitant to order one sight unseen. Also, the honeycomb/parallel coil issue is puzzling. The pics posted certainly look like the least expensive BE model which is parallel construction. So, is the Willow really the Alpine and is there a direct correspondence to the other names assigned by various retailers to these mattresses (i.e. DesignSleep Riviera). The unique names and minor variations are reminscent of the major mattress makers’ games! :frowning: All of the retailers sell the same adjustable slat foundation and really recommend it but there is considerable discussion of that issue as well. Sure would be nice to get some feedback from someone who owns one of these!

Hi anonymous!

I just checked DesignSleep as well.

It looks like the “Euro Simple” is the least expensive option at $1518 for king. It’s a parallel coil layout & fewer coils (880 for queen) than the Willow / Alpine / Riviera. Here’s the pic:

The Riviera appears to be the same as the Willow & Alpine- honeycomb coils & more of them. Having a hard time attaching two photos to the same posting, so will attached it next.

I agree that the pricing at Sovn is way out of line with every other store in the country that sells these beds. Still determining my approach on that if I decide to go with this line of beds.

I really want to love the all latex, but just not sure I love that feel.

Oops- the photo above is the Riviera- honeycombed.

Below is the Eurosimple- parallel:

Wow! I just posted a very long post about similarly constructed mattresses from the Natural Mattress Store (EcoCloud), The Natural Bed Store, Keetsa, Dunlopillo, and so on for feedback and it just disappeared when I hit post :frowning:

Will try to repost tomorrow.

The long and short was that I was wondering if there are other similarly constructed beds I should consider. I like the quality and simplicity of Berkeley, but I am not married to that brand- nor to the Sovn prices if there are other ones I should think about too!!!

Also very interested to hear what you discover about these coil beds on the flex slats Phoenix!

When you go to Sovn, Sleep Works, etc…- they only offer the flexible slats or solid wood foundation. No boxsprings.

Hello all,

I talked to http://www.sleepworks.com/ and got the “scoop” right from the horses mouth. They were very helpful in “sorting out” the different coils and models and I certainly recommend them as the place to get good information about BE. (UPDATE: they are now making their own mattresses that use similar components in a similar range of designs).

They use 3 different types of pocket coils in all their current models. One of these is the honeycomed “bi level” model used in the Alpine. The Nordic and the Alpine ES use the same pocket coil which is parallel and not bi-level. The Nordic 11 uses a denser parallel coil system with more coils. Some of their coils come from Germany and some come from Star Springs in Sweden who incidentally also makes the innersprings for Hastens.

They also made a model last year which has since been discontinued which had less coils and which some outlets may still be selling as a more economical version with less coils. It was not as popular in spite of the recession which was the main reason they introduced it.

All their models come with the ability to choose two different firmnesses in the comfort layer and two different firmnesses in the support core (both the innersprings and the latex) which is the basis for the four different levels in each model.

Their flexible slat system comes from Spain (it’s not Roewa) and when I asked about the ability to support a pocket coil which had no insulation on the bottom she said that they had never seen an issue with this and they monitor any issues with their mattress very closely. The slats are very close together and this is probably why it works so well. They do this of course because of the ability of the tension adjustable slats to increase the ability of the system to align with the natural curves of the spine. They did give me the name of their designer to talk with if I wanted more information about the theory behind their choices but I am satisfied that it does not present an issue.

So hopefully this helps to cut through any muddle about the different names at all the different independent outlets. With the exception of last years lower cost model which may still be sold at some outlets … all of the pocket coil models at every store will match up to one of the 4 models at Design Sleep.

I also asked her about the prices charged at Sovn and she was well aware of the fact that they were charging much more than the rest. Each outlet is independent and can set their own prices though so BE does not decide any limits to their pricing. She did say though that they can ship a mattress anywhere in the country and for a heavier King Size this would cost under $500. While this would add significantly to the price … it would still be a lot less than Sovn is overcharging and it would also save on taxes which would bring the cost back down a little. With this information … Sovn may be a little more willing to price match … and if they didn’t go lower (not even the same) than the equivalent model ordered out of state … I would probably use them to test the different options and then order elsewhere once I had made a decision as to model and comfort level (and tell them that I was) until they “got the message” that their price gouging is not so “secret”.

All in all I was very impressed with her willingness to help and the transparency of the information she gave me.


Hi Sleepless,

I feel your pain :frowning: . There is nothing more frustrating than spending an hour or more on a long post and then having a glitch make it “disappear”. Of course those are the times I haven’t saved it along the way (I usually highlight and copy it every 5 or 10 minutes when I am working on a long post).

In any case … I think I get the gist of where you were going and my answer would be that I would first check with local manufacturers who will often make a latex over pocket coil mattress. Many of these will also custom build it if your testing experience of what was on their floor wasn’t quite “right”. Dallas has some very good independent manufacturers and quite frankly this is where I personally put my focus. BE may still come out ahead in terms of preferences because the independents may not source their materials from the same places but I would be very surprised if in terms of quality and value the independents didn’t come out ahead.

I would also base my choices more on testing for PPP (pressure relief, posture, and preferences) than on the technical specs of the coils which are more about the means to get to PPP and are very much a secondary and in many cases highly technical consideration (assuming a quality pocket coil is being compared to a quality pocket coil). If a manufacturer uses quality materials … then the coil won’t be the weak link anyway and they (like BE) will almost always give you good information about any durability issues with any of the materials they use.

In terms of some of the brands you mentioned …

The Natural bed store is the main outlet for Land and Sky which make some very nice Dunlop latex mattresses. They also make pocket coils and Bonnell coils with latex hybrids (the pocket coils have a coil count of 858). While they are very nice, focused on natural and organic materials, and offer exchangeable layers … they are not the best value of the many options out there.

Keetsa is a budget Zinus brand which has a “green” focus but not as much green materials. It is a stretch at best to call polyfoam or memory foam green just because some of the petrochemical polyols have been replaced with plant oils. Their iCoils are designed with compressed shipping in mind (another big focus for Keetsa and other Zinus brands) more than quality alone. They are all made by Zinus in China and while some of their mattresses have OK value … there are better options IMO.

Dunlopillo used to pour Talalay latex until a few years ago when they went bankrupt. The brand name survives however and is owned by many different groups in different regions around the world, each of whom use different suppliers and materials in their mattresses. In the US … Latex International owns the Dunlopillo brand and their talalay would be in any Dunlopillo mattresses sold here. Paramount became the first Dunlopillo licensee in North America a little over a year ago.

I hope you can remember the rest of what you posted … it’s always the “good stuff” that gets lost.



This is very helpful! And the one I liked on the floor at Sovn was indeed the ‘Alpine or Willow’- honeycombed bi-level coils. And they are very dense.

I do like the relative simplicity of their system- 2 levels of firmness in the core & 2 in the comfort layer. Whether the core is coils or latex or coils & microcoils.

For the coils (Willow) for example-
A- softer core + softer top
B- same core as A + firmer top
C- firmer core + softer top (25ILD talalay latex)
D- same core as C + firmer top

Very good to know about the flex slats. So, it sounds like that would be ok afterall.

It also sounds like their latex is 100% natural. “Our latex foam is 100% natural and is certified by the Öko-Tex Standard 100 confirming that it conforms to the strictest European standard for harmful substances and chemicals in mattresses.”

I know you’ve mentioned on other posts that in softer talalay ILD’s a blend might be more durable. At 25 ILD, do you think 100% natural will still be very durable? That’s what they’ve told me their ‘softer’ latex top layers are- 25ILD.

Hi Phoenix,

To your last post- yes, lesson learned to copy every so often. Frustrating! It was a long one too!

But yes, you were on the right track with where I was going. I’ll continue to do some local research as well.

"I would also base my choices more on testing for PPP (pressure relief, posture, and preferences) than on the technical specs of the coils which are more about the means to get to PPP and are very much a secondary and in many cases highly technical consideration (assuming a quality pocket coil is being compared to a quality pocket coil). "

The reason I was mostly asking you about technical stuff is just to weed out the junk. Unfortunately, as you know in this industry, you can’t always relay on feel to lead you to a quality product. I’ve made that mistake before! I do like how BE “fits” you for a mattress when you go in. They start you off, ask how it feels, look at your alignment, and then move you around to different beds from there. You don’t know the details of each bed until the end once you’ve “picked” one based on alignment and feel. That’s how I came to the Willow- on feel. But, then I wanted to do some deeper due diligence on the actual quality of each layer of materials to ensure that the mattress will keep that same great feel for many years. Since that seems to be my problem. I am a good picker actually :wink: I like firmer mattresses with a little cush on top and I am usually extremely happy with them for many months. But ultimately, the quality of the materials is not good enough and the feel changes, the layers start to sag or mush, and then I am unhappy and in pain.

So- on the BE construction, I am confident from our other discussions & your other posts that the latex layer should be of high quality and should not cause a sag problem. So, in this model, the wildcard for me becomes the coils. And I just wanted to get as much technical info as possible so you could give me your opinion on the coil quality & durability :slight_smile:

The thing I REALLY love about BE (and similar styles) is the simplicity of the layers. Either coil core + 2" of latex, or 6" latex + 2" comfort layer latex pretty much sums up most of their beds. They do have a few with microcoils, but still, you can unzip the bed, look inside, and see quite simply exactly what is there. As opposed to so many other mattresses that something like this…and while I now consider myself to be a very educated consumer, this is still greek to me!

Quilt - Top of Mattress

High Loft Fiber
1" Hypersoft ®
1.5" X .5" Convoluted Hypersoft ®
Comfort - Padding Layers

2" High Density SuperSoft Foam with VRT™
.5" Memory Foam
Correct Back Support System

Coil System:
Individually Wrapped Coil Innerspring
2.5" Foam Encasement™

Hi Sleepless,

Are you ever right about that! I think you’ve encapsulated the “chain store experience” in a single sentence :slight_smile:

The 100% natural is a very high quality material and very durable compared to other types of foam. The only comparison where it may fall a little short is in comparison to blended Talalay and in an ILD of 25 this would not be a major issue. The other side of this is that it is more “elastic” than the blend and the slight difference in feel and the “naturalness” (is that a word?) of the 100% natural is more desirable than having the absolute best durability for some. In a mattress like the Sovn … the layer can be replaced anyway without replacing the whole mattress.

I also agree that “translating” the sometimes arcane language of describing the specs of similar materials with a million different “proprietary” names is one of the most frustrating parts of the industry. Is “bafflegab” a word? :silly:

Your 10+ years criteria is I think still the most likely outcome :slight_smile:


Marvelous! Well, this year has been a process of elimination if nothing else! No more big brand names and big chain stores for me. End of story- unless it’s CostCo only b/c I can return forever and it’s inexpensive if that were a route we decided to go b/c it would still be financially safe. Although, still a headache if you keep having to return and swap.

So- no more Westin Heavenly beds, no more S brands, no memory foam, and unfortunately from what I can tell, no 100% solid latex mattresses for us either- not as a result of quality, just feel. Maybe we just never got it right, but it was becoming too much hassle.

But- I do love latex in the comfort layer it seems. And to date, I think this combo of high quality pocket coils + latex on top seems to be a worthy contender. I like the quality of products and frankly the simplicity of design and understanding what’s inside. And being able to see what’s inside!

So- I’ll focus in on pricing with Sovn, Sleep Works, etc… and talk with some local manufacturers about this kind of product as well and go from there!

Many thanks Phoenix!!!

Ok. Not to digress here. But- is it safe to say that this kind of set up (high quality coils + ~2" of natural latex) will be more durable and keep it’s shape/feel/no sag longer than the Tempurpedic Bellafina? Or should that one stay in the race a little longer?

Or would it be wiser to proceed with the coils + latex and add 1" of memory foam if I still need something ‘softer’?

Hi Sleepless,

Regarding the Bellafina vs the Berkeley Ergonomics … there are some “unknowns” in the equation … so lets look at it layer by layer.

The BellaFina core is high quality polyfoam. In the BE its high quality pocket coils. This one is a tossup in terms of durability as the bottom of the mattress is not the weak link in either.

The transition layer in the Bellafina is the latex … but the type is unknown. It is almost certainly a lower quality of latex which would be either SBR Dunlop or Blended Dunlop. In the BE … the transition layer is the upper part of the coils. I would also call this a tossup. If the Bellafina had a 100% NR Dunlop transition layer, I would give it the edge but it didn’t weigh out at what would be typical for this. If it had all SBR latex or used latex with some type of fillers, then I would give the BE the edge.

In the comfort layer, the Bellafina has 5.3 lb memory foam … one of the higher qualities of memory foam. In the BE there is 100% NR talalay 25 ILD. Part of the “unknown” in this is that the NR talalay has not been out long enough to really know for sure what the typical experience really is over the long term. My guess is that this is a tossup as well with perhaps a slight edge to the Talalay.

But there’s more … and if this turns out to be correct … you heard it here first :slight_smile:

In an earlier thread that you were asking about the Bellafina … I worked out the density of the latex based on the percentage weight of each material on the law tag and the known thickness of each material. While I was at it I also worked out the density of the polyfoam core and the memory foam on top. The latex worked out to be a density that suggested SBR or blended Dunlop although this is not necessarily true. The polyfoam also worked out to their published specs (a little under but then it’s also convoluted which would reduce its overall density so it seemed to be correct). The memory foam however worked out to be less than 5.3 lbs density. This was curious so I checked my math and there was nothing wrong that I could see.

So I went out to the store and took a picture of several law tags (with the willing help of the store owner who knew why I was doing this and was a great guy and also curious). I then did the same calculation on several of their mattresses using the percentage weights of each material (including some 7 lb memory foam in the HD series and some 4.2 lb memory foam in the cloud series) … and ALL of their memory foam worked out to be under the published density.

This was several weeks ago and quite frankly I am a little puzzled. I can’t find anything wrong with my math but the results are there in front of me. I also find it hard to believe that Tempurpedic has changed the density of their memory foam without changing their law tags … so I really don’t know what to think.

This could mean that Tempurpedic has changed their formulation and is using a different foam and that their law tags haven’t caught up. Speculation could also take me in the direction of MDI foam vs TDI foam where density and feel have more diversity and wider possibilities. It could also mean that they have simply used cheaper memory foam. Whatever the case … and without translating any of this into “fact” because I could simply be missing something I don’t know about yet … it has certainly introduced another possible variable into the durability of Tempurpedic for better or for worse.

I’ve been “sitting on” this information for weeks and I’m hoping that others will duplicate my “experiment” and either confirm what I came up with or find out where I went wrong. I thought I’d post my speculation now though and I’ve mentioned this to a few people so perhaps there will be more discussion about this in time.

Anyway … this is the best “layer by layer” comparison I can make even though there is some “prediction” and “speculation” involved. With the typical pricing between the two … I would say that the BE has better value (the Alpine is $1600 queen) than the Bellafina ($2599 queen).


Wow. This is a very interesting twist. I have to say, nothing surprises me anymore with these big name brands. Your calculations are beyond my understanding, so not sure I can replicate, but would be interesting if others find the same.

I’m hoping to get my husband back to Sovn soon to try the Willow C and go from there. Have done a little digging on independent groups as well.

How long has natural talalay been used? I know the older latex beds that some people still have hanging around (including my parents) are dunlop I believe. Maybe by Uniroyal?

Honestly, if you feel that we can expect the BE coils to hold up for at least 10 years or so, I do like that you can just replace the 2" latex piece if needed in say 5 years for like ~$500 or less.

Sorry for the delayed response this week- was traveling for work.

Hi Sleepless,

100% NR talalay has been available since early 2005 (at least by latex international). I’m not sure when Radium started producing it but it would also be “relatively” recently. The NR talalay version was more in response to consumer desire for more natural materials rather than a desire to produce a “better” or more durable material. The talalay process itself has been around since the late 1940’s. Most of the “decades old” stories about latex mattresses would be from Dunlop single layer mattresses which were commonly sold as single layer mattresses or from blended Talalay.

I certainly believe that the BE coils are durable and would hold up for much longer than 10 years. If anything … the NR talalay in this mattress would be the “weakest link” although I would expect that it too would hold up for 10 years or longer and like you say can always be replaced for far less than the cost of a whole mattress. I personally like the NR talalay in terms of its slightly greater elasticity and feel even though I know that it may be less durable than the blend.

All in all … the BE is a good choice IMO in terms of materials and durability and the only way you may be able to do “better” in terms of a mattress that fit your preferences and needs would be through other independent manufacturers which use similar materials in their mattress.

An example of a similar mattress is the Diamond Maple Hybrid which was under discussion in this thread. There are some similar style mattresses (although not exact duplicates) made by one of our members (Parklane in Washington and Oregon) here as well for reference.