Hi there Joe and thanks for the order and thank you so much for reaching out on this! Generally speaking, 9" of latex is plenty for anyone under about 300 pounds (in our experience), but I have talked to a few (but only a few) customers that decided to upsize the mattress to keep from feeling like they’re bottoming out, so it’s really not something that comes up often. Nonetheless, it’s certainly an option. Some customers will rearrange the layers to make it firmer, but at that point you’re making it more comfortable to sit on, but possibly less comfortable to sleep on. If you decide to upsize your mattress, please call us and we can discuss the process with you.
Anything you have between yourself and the latex affects the way you contour into the latex, making for a firmer feel and adding more surface tension to the mattress, and the inch of wool in the cover certainly is no exception. There are two types of ‘break-in" periods that I normally address – your body’s own adjustment period, which ranges from 0 nights to 30 nights or more. The second break-in period is the amount of time it takes for the cover to break in. We ship out our covers to be tight because we understand that the cover will loosen up and break in over the first 2 months of use, at which point it will be the “right size.” Since the cover is tighter than “normal” right now, it’s giving the mattress more surface tension and therefore a firmer feel. Once the fabric and stitching in the cover breaks in and loosens up, you will be able to sink into the mattress more, making for a noticeably softer feel. It can take 1-2 months for the cover to break in, and it will feel noticeably softer after this, but shouldn’t soften up thereafter until the mattress is many years old.
Generally speaking, there are two causes of back pain when attributed to a mattress: one is a lack of “primary support,” which is just the general firmness of the mattress or mattress core. The second cause is a lack of “secondary support.” Secondary support is needed to fill in the gaps between your body and the mattress – back sleepers normally need secondary support to fill in the gaps between the small of their back and the mattress; side sleepers normally need secondary support to fill in the gaps between their mid-section and the mattress. If these parts of a person’s body aren’t supported by the mattress, their muscles will work throughout the night to hold these parts of the body up, and by the time they wake up they’ve got back pain.
Although Talalay is renowned for being great at pressure relief on your hips, shoulders, or anywhere that contacts the mattress, it is also better at adding secondary support to the mattress. Are your top layer(s) Talalay or Dunlop? Adding a topper to the mattress will add a ton of secondary support and will make for a really plush and enveloping feel. If your latex layers are split, you can borrow half of a soft layer for your partner’s side of the mattress to put on top of the mattress cover and this will let you know what to expect out of a soft topper.
With all that said, I think it’d be a good idea to increase the primary support to see if the back pain goes away, and to do this, you would just unzip the cover and move the firm layer to the middle. If this helps, then you know a lack of primary support is / was the problem. If this doesn’t help at all or things get worse, then you know you either need more Talalay in the mattress or you might want to consider adding a topper.