Hi GenericMattressShopper,
If you are attracted to the idea of designing and building your own mattress out of separate components and a separate cover then the first place I would start is by reading option 3 in post #15 here and the posts it links to (and option #1 and #2 as well) so that you have more realistic expectations and that you are comfortable with the learning curve, uncertainty, trial and error, or in some cases the higher costs that may be involved in the DIY process. While it can certainly be a rewarding project … the best approach to a DIY mattress is a “spirit of adventure” where what you learn and the satisfaction that comes from the process itself is more important than any cost savings you may realize (which may or may not happen).
If you decide to take on the challenge then I would either use the specs (if they are available) of a mattress that you have tested and confirmed is a good match for you in terms of PPP as a reference point or use a “bottom up” approach (see post #2 here).
Organic certifications such as GOTS or GOLS are different from safety certifications such as Oeko-Tex, Eco-Institut, or CertiPur.
Post #2 here and the posts it links to has more information about safe, natural, organic, “chemical free”, and green mattresses and mattress materials that can help you sort through some of the marketing information and terminology that you will encounter in the industry and can help you differentiate between them and decide on the types of materials you are most comfortable having in your mattress and help you answer “how safe is safe enough for me”. These types of issues are complex and are generally specific to each person and their individual sensitivities, circumstances, and specific criteria.
Latex doesn’t have a GOTS organic certification which is used mainly for textiles such as wool or cotton. The organic certification for latex is GOLS. There is more about organic certifications in post #2 here and post #2 here.
All the latex you are likely to encounter (whether it’s Dunlop or Talalay or made with natural or synthetic rubber or a blend of both) will have either an Oeko-Tex certification or an Eco-Institut certification which are roughly equivalent.
There are a wide range of different firmness levels with innersprings from soft to firm and there are different types of innersprings as well (see this article and post #10 here) and there are also a wide range of firmness levels for latex cores so it isn’t possible to make these types of generic comparisons between two very different components. It would depend on the specific innerspring you were trying to “match” but even if the firmness of a specific innerspring and latex core was roughly comparable the response curve and “feel” would be different between them. There is also more about how innerspring support cores compare to latex support cores in post #28 here and more details yet in post #2 here.
The list of the better online suppliers I’m aware of for latex components and layers is in the component post here. Several of them sell GOLS certified organic latex but you would need to check their websites or talk to them on the phone to confirm they currently carry it.
There is more information about wool toppers in post #8 here and the posts it links to and there is a list of the better suppliers I’m aware of for wool toppers in in post #3 here.
Yes … layer thickness is one of the more important specs in a mattress and can have a significant effect on the feel and performance of a mattress. Thicker comfort layers than you need can lead to alignment issues and lower back pain. There is more about primary or “deep” support and secondary or “surface” support and their relationship to firmness and pressure relief that may help you clarify the “roles” of different layers in a mattress in post #2 here and in post #4 here and there is more about some of the specs that can be important in a mattress design in post #2 here.
The Spaldin US website is here but you would need to find a retailer that sells them because they don’t sell direct to consumers. Spaldin replaces a fairly large percentage (40 - 60%) of one of the two main petrochemicals used to make polyfoam and memory foam (the polyol) with a polyol derived from plant oils but the rest of the formulation is still petrochemicals and the other chemicals used to make it (including the isocyanate which is the other main chemical in polyurethane foams) is still a petrochemical. There is more about so callecd “plant based” foams in post #2 here. They are certainly not natural or organic although they are “safe” and they have an Oeko-Tex certification for their mattresses as whole not just the individual components inside it. A forum search on Spaldin will bring up more information and feedback about them.
Nest Bedding carries Spaldin mattresses (their Gemma mattresses) but I would make sure that you can find out the information listed here for any mattress you are considering so you can confirm the density/quality of all the materials inside it and make sure that there are no weak links in the design and make more meaningful comparisons to other mattresses. NOTE ADDED: Nest Bedding is also now a member of this site
I consider them to be a knowledgeable and reliable supplier that will provide you with accurate information about all of their products and any certifications they have.
I don’t have any other information about them other than what is on their website so you would need to find out the information you are looking for from them.
The component post includes a list of sources for mattress covers that you can use to enclose the components you choose to finish your mattress.
There is more about mattress allergy encasements in post #2 here.
There is more about the pros and cons of different types of mattress protectors in post #89 here.
The pillow topic here has more information and guidelines about choosing a pillow.
There is more information about sheets and bedding in post #7 here and the posts and topics it links to.
Phoenix