I am wondering which of these two “soft” toppers would be the most supportive:
A 4.75 density 16-18 ILD OR A 4.0 density 20 ILD, both 3" thick to be put on top of a too firm mattress to make it softer. Also, they are from two different but reputable companies and were recommended by the salesperson on the phone who assured me these soft Dunlop toppers could provide support for a 300 lb. back sleeper. Also, I have had medium firm 30 ILD Dunlop toppers which I found to be too firm. No $$ for any other solutions. Thanks.
“Support” is often misunderstood and many people believe incorrectly that “firmer is better” or “more supportive” when the real goal is to keep the spine in good alignment and this requires the type of contouring support that allows some parts of the body to sink in more and some parts of the body to sink in less and this will vary on an individual basis. There is more about primary or “deep” support and secondary or “surface” support and their relationship to firmness and pressure relief and the “roles” of different layers in a mattress in post #2 here and in post #4 here that may also be helpful in clarifying the difference between “support/alignment” and “comfort/pressure relief” and “feel” and how they interact together.
If your mattress is too firm but is still in good condition and doesn’t have any soft spots (virtual impressions) or visible impressions or sagging and you just need some extra softness and pressure relief (and the foundation under the mattress is also in good condition without any soft spots or sagging as well which can also affect the sleeping surface of the mattress) then a topper can certainly be an effective solution.
While there are too many unknowns, variables, and personal preferences involved for anyone to be able to predict which topper will work best for a particular person in combination with a specific mattress (different mattresses will affect the choice of which topper will work best for a particular person) … post #2 here and the topper guidelines it links to can help you use your sleeping experience as a guideline and reference point to help you choose the type, thickness, and firmness for a topper that will have the least risk and the best possible chance of success. It also includes a link to a list of the better online topper sources I’m aware of as well.
It’s very unlikely that a 4.75 lb density 100% natural Dunlop latex topper would be 16 - 18 ILD and it’s much more likely that either the density is lower or the ILD is higher. Post #2 here can help you translate the approximate density of 100% natural molded Dunlop into an approximate ILD range.
I also don’t know whether the second topper you mentioned is 100% natural Dunlop but I would also keep in mind that the ILD of different types and blends of latex also aren’t directly comparable to each other as well (see post #6 here) so I would make sure that you choose a knowledgeable online supplier so you can have a more detailed conversation with them that can help you compare the firmness of their toppers to other types and blends of latex that they are familiar with.
When you aren’t certain whether a specific topper will be a good “match” both for you and the mattress you are using underneath it then the return or exchange policy can also become a more important part of the “value” of a topper purchase just in case your choice doesn’t turn out as well as you hoped for.
While this would be in the firmness range that would work for many people in your weight range based on “averages” … if the topper you tried was 100% natural Dunlop, was also 3" thick, and the ILD was correct and it was just too firm for you then it would make sense to try a topper that was in a little softer ILD range.
I found three sites with a 4.75 density and 16-18 ILD 100% Natural Dunlop Latex Toppers… They are Rocky Mountain Mattress, Ultimate Sleep (Ergo) and Sleep Warehouse Just wanted to inform you that they are out there…
I know they’re out there and there are probably more than you mentioned … that’s why I posted the caution in my last reply. If the general firmness is correct and it’s just the density that is incorrect then it wouldn’t matter but when you are uncertain then the exchange/return policy for the topper would become a much more important part of the :value" of your purchase just in case your topper doesn’t turn out as well as you hoped for when you sleep on it in “real life”.