Constructing an HR foam mattress

Hi DanielH,

Thanks for the feedback about your experience with foamonline both here and in your other post today.

It can be very frustrating to order a product where getting exactly what you order is important and you end up getting something different. In cases like this … I would hope that the retailer would do an exchange at no cost (including shipping) to correct their error (and it is their error). 50% off on another layer may be fine if you need both layers but it’s no bargain if you don’t need the original layer that you ordered.

I also noticed their chart is now more accurate and also the different information in their “check price” information. I may need to call them as well though to update my information because it appears that what they are selling may not be Latex International (which has different ILD’s) and is possibly Radium Talalay (both are good quality).

It seems that they may be a good source for polyfoam but I hope they clarify the questions about their latex.

I also hope that they decide to do the right thing since it seems based on their offer of 50% off that they are acknowledging that they made an error. I hope you let us know how things work out.


After nine months or so of sleeping on the foam, while my side has always been too soft for my middle, or perhaps just too firm for my shoulders and legs, my wife who initially loved her side of the mattress is finding that it has begun to soften uncomfortably. I know to expect some softening in the initial days of sleeping on a foam, but it has been a more recent change that makes me wonder if it is a lower quality foam than claimed, being that this isn’t a “breaking in period” softening, I am left to guess that it is a “breaking down” softening. Supposedly it is 3lb HR foam. With this doubt as to the foam quality, plus my receiving different ILD foam than I thought I was ordering leaves me less than confident in ordering from them again in order to fix my side or to refresh her side.

Here’s what we have, 7" total thickness of supposedly 3lb HR foam:

My side:
3" - 23 ILD
4" - 30 ILD

Wife’s side:
2" - 23 ILD
5" - 30 ILD

One thought for refreshing her side and possibly fixing mine is to add another support layer under our current setup (along with switching out my top layer to a 15 rather than the current 23). I think this because we did recently place a 5" yellow foam mattress (old and of unknown quality) under our current set up for a week or so, which brought our thickness from 7" to 12". This we did recently enough that it was after my wife’s side had begun to soften uncomfortably. The first night on it we both woke up in the same position we fell asleep in. Best sleep I have had in some time, albeit I did have to add support to my middle with a folded up towel. But man, it felt good to sleep so well. Seems strange, though, that her too soft side would be able to feel more comfortable, if only for one night, by adding another base layer. But I suppose the interplay of too soft, but too thin (at 7") was less comfortable than too soft but thick enough (at 12" with the old 5" mattress underneath). The second night, back to tossing and turning a little for me, and each night for a week or so got worse for both of us so we removed the old 5" layer which seemed that it just couldn’t maintain it’s support and/or resiliency for more than that very first night. But again, when thinking to try more experimenting with new layers, I’m not very confident in ordering from again, and haven’t found other comparable sources either price-wise or claimed-specs-wise.

This has had me considering Dreamfoam/Brooklyn Bedding. I emailed Chuck through Amazon, but they won’t do different firmnesses for each half on their lower priced Ultimate Dreams Latex (but maybe two different halves may not be necessary for us with the materials they use), and I’m concerned about not being able to accurately translate our (supposed) ILD’s of (supposed) HR foam into their ILD’s of HD foam and latex so I can use our current setup as a starting point for making a solid guess on what firmness to order from them. Chuck offered some general descriptions of what they have, e.g. “6 is considered a medium feeling mattress (not to firm not to soft)”, but this seems an unusable subjective description, which would vary from person to person. He did give specifics, their 2.35 lb HD base being 32 ILD, and their latex varying, a “6” being a 28 ILD, and their “7” being a 24 ILD. That 32 ILD base concerns me since my current base is 40 and not sure if it is firm enough. But my main problem may be my top. I had intended to order a 3" thick 15 ILD 3lb HR top for my current mattress set up, but received a 23, and think that might be the feel to try and achieve when ordering a Dreamfoam Ultimate Dreams Latex, but not sure how to translate the feel of my set up to theirs. It might also be best to shoot for firmer so as to be able to add a topper to soften, since firming a too soft mattress can’t really be done.

Further thinking out loud, maybe I could order an Ultimate Dreams Latex, but without the cover and quilt layer. If they’re willing to do this, it might reduce my price, but even more important, it would allow easier adjusting our individual sides after the fact if it isn’t quite right, giving us the option to replace the latex layer entirely, or alternately add another one to it.

Any thoughts?

Hi DanielH,

Is the HR foam you ordered showing impressions or just softened?

If there are impressions I would call foamonline and ask them about this.

You could test the density by weighing it and calculating its density. Height x width x length in inches divided by 1728 will give you the cubic feet and then dividing the weight by the cubic feet will give you the density. If the density is correct it would be very unusual for it to soften considerably beyond the initial break in period.

Keep in mind as well that when the foam goes through it’s initial softening that it may take some time for your body to notice the effect of sleeping out of alignment if that’s what’s happening. It’s like something that creeps up gradually but may become noticeable more suddenly than it actually happened. It may seem that the change is more recent when it could also be that you are only noticing it more recently. This is like when you don’t see someone for a long time and you notice all the changes but someone who has been around them every day doesn’t notice any changes at all until something else happens to make them more aware of it and they suddenly notice something that they didn’t before. This is probably the reason that your extra 5" felt good for one night and then didn’t after that. The foam itself probably didn’t change much if at all from one night to another. Of course it could also be foam softening but I wanted to bring up all the possibilities. I would also rule out the possibility that it’s connected with what the mattress is sitting on.

No matter what the cause or whether it is subjective or objective … I would at least talk to foamonline and ask for their feedback.

Your layering and the many variables involved are much too complex for anyone to predict which layering you may do best with based on any “theory at a distance”. Unless you have a good idea of the effect of every change you are considering you would need to go by trial and error. I would try to simplify your “target” though and have a clear and precise idea of exactly what you are trying to change in the mattress and the degree of change you are looking for as best as you can define it (in pressure relief and alignment terms) and then “translate” this into which layers may need to change in terms of thickness or ILD and by how much. With pressure relief you would generally be looking at changing the thickness or ILD of the upper section of the mattress and with alignment you would generally be looking at changing the deeper layers or the thickness of the upper layers. This would require some knowledge of the potential effect of changing every layer and layer thicknesses … ideally with some personal reference points of local testing (although with polyfoam this may be difficult).

I would also keep in mind that latex ILD and polyfoam IFD is tested on different layer thicknesses so they are not directly comparable and also that compression modulus is just as important if not more important than ILD when you are trying to design a mattress.

In the end … even most mattress manufacturers will go through a great deal of trial and error when they are designing a mattress and the odds are good that to some degree you may need to do the same.

If you have some more specific questions that only involve the effect of changing one variable (the ILD or thickness of a single layer for example) I’d be happy to give you some thoughts about what a specific change may do but with all the many variables both in terms of materials and design you are considering any reply about the combined effects of everything you are considering would take a book (or at leas a few chapters) on mattress design theory and of course this is outside of the scope of the forum.


I checked, and there is an impression in both our sides of the mattress. A distinct concave curve in the hip area, which is also very much softer by feel than other areas of the mattress. The curve is especially noticeable in the minutes after awaking, but even at the end of the day when the bed went unlaid on, I checked, and there is still a perceptible curve. I measured and weighed my wife’s 2" layer. It is 75x27x2, and weighs 5 lb, 12 oz, which I calculated as follows:

75x27x2 = 4050
4050/1728 = 2.344
5.75 lbs. / 2.344 = 2.45 lbs per sq ft

Is my calculation correct? You suggest the impression alone is enough to enquire about it, but if this calculation is right, not only is the foam not the 3lbs they claim, it is a shade under the 2.5 lb your article explains is required in order for it to be claimed as HR foam.

On a non-foamonline note, I think we’re going to start fresh, new mattress. (Our current set up can be used in another project, so not wasted.) Likely going with a firm base, soft top, seeking for wiggle room to soften it if needed. My wife’s 30 ILD base (if it was really a 30) was comfortable at first, but not the firmer feel she prefers. My base was (supposedly) a 30 too, and not firm enough. Considering somewhere between a 5-6" base at 36 or 44 ILD from either dreamfoam or another supplier, with a 3" 19 ILD talalay latex topper from dreamfoam/brooklyn bedding. My concern with sourcing the base from dreamfoam is they claim a 2.35 lb density base – they also call it HR (?) – which is less dense than what my calculation indicates our current foam is. Should we expect the same level of softening/impression, or might other characteristics of the foam allow it to hold firmness with use over time?

Hi DanielH,

Yes … your calculations are correct to the degree that the measurements are accurate (it could have a slight variance in thickness which could make a small difference in either direction).

HR foam actually has 3 separate requirements in order to be legitimately called HR. One is that it needs to have a density of 2.5 lbs. The second is a compression modulus of 2.4 or higher, and the third is a resilience of 60% or higher.

Density (or more accurately unfilled polymer density) is the biggest factor in durability. HR foam that was say 2.5 lbs and HD (conventional foam) that was the same 2.5 lb density would have roughly the same durability. The difference between them would be more in their performance and feel (and cost because HR is more costly to make)

There are also foams that are “high performance” or “high comfort” foams that are less than 2.5 lbs but use a different formulation than conventional foam to achieve a higher compression modulus and higher resiliency.

I should also mention that when foam is ordered that there is a +/- tolerance so that if you order say 2.5 lb from a supplier with a +/- tolerance of .1 lb it could be anywhere from 2.4 to 2.6 (and the odds are much better that it would be 2.4). The tighter the tolerance of the order the more expensive the foam.

Overall though it seems that you have both an impression issue and a density issue and I would certainly talk with foamonline about both. I would also appreciate it if you let us know what they say about both of your issues.


I have left two messages with since my last post, but with no response to my inquiry about the foam density and breakdown. They ignored my follow up message informing them I’d file complaints with the BBB and with the California Department of Consumer Affairs, as well as attempt a chargeback if possible. In my initial request to initiate a chargeback I was told the orders were placed too far back in time, but I will pursue this further to see if it is still possible. If only I had weighed the foam on receiving it. Too bad I trusted them to actually send me the product they described.

Conclusion: I can not more strongly recommend against purchasing from or (aka Upholstery Decor Inc.).