I’m ready to try D-I-Y makeover on my 12-year-old Beautyrest Classic mattress. It’s a queen size Simmons spring base with 800 pocket coils, 15-gauge with edge support. On top of that is a 1-1/4 inch layer of polyfoam, then a 1-inch layer of eggcrate foam, then a 1-1/2 inch thick, polyfoam-filled quilted cover. The mattress was originally described as “plush-firm”. There’s no pillowtop, it’s a tight-top style.
I realize I could replace all 3 foam layers with a 3-inch layer of medium latex, put it into a zip-up casing with a wool-filled quilted cover and call it a day. I see that would mirror the construction of several of the latex hybrid mattresses being sold by various vendors right now that seem to get generally positive reviews.
But the other thing I’m considering is putting in layers that are a little closer to the original construction – a 1-inch layer of polyfoam on top of the spring base for transition, then a 1-inch layer of eggcrate foam, topped with a 2-inch layer of latex in a new zip-up casing with wool quilted cover.
How do you think those two construction methods would affect how the mattress feels?
And can you explain why every big-brand innerspring mattress seems to contain a layer of that eggcrate foam? What are the benefits in using the eggcrate layer as opposed to using all flat layers or a single thick layer of latex?
Unless money is extremely tight, or if you’re just a fan of being a mattress “mad scientist”, I’d recommend starting from scratch and not reusing your innerspring unit. It will have gone through 12 years of fatigue and the innerspring unit will have taken a bit of a set. Also, the nonwoven material covering the springs will have become worn, especially along the glue lines, and you’ll notice some tearing and fatigue in these areas. The biggest concern I’d have would be for a healthy sleep environment, and your mattress is like an accordian, pushing air out and sucking things in with every movement. There will be some gross stuff embedded in your innerspring unit.
But with that being said, if you wish to continue…
Your idea of replacing all of the padding layers with latex would be a simpler and better option. You would have quite a few references online of popular combinations that tend to work well together, and latex is a much more durable product than your typical polyfoam.
If you’re attempting to replicate the polyfoam layers within your old mattress (which I wouldn’t want to do because the foam itself wasn’t particularly high in quality (density), you’d need to know the density and ILD of each of those foam layers, along with the exact type of foam to match things like the Support Factor, Dynamic Fatigue, Resilience, Tear Strength, Hysteresis, etc. Most likely you won’t be able to find the exact foam layers (technology and specs change), so you’re now left to find something that you “think” feels like your old foam. You can’t compare to the current foam layers, because they feel drastically different now from when they were initially placed within your mattress. This now puts you in the category of a mattress designer, which is a skillset very few people in American have, and you’re attempting to find different layers of polyfoam and be able to predict how they will work in combination relative to what you’re attempting to replicate. There are a lot of variables here, so you can see why I don’t recommend this option. Working with latex would be much more desirable, on many levels.
No all mattresses use convoluted foams, but they can offer a different feel and compression modulus as compared to a similar version of the same foam in a flat sheet. Like flat sheet polyfoam, look for higher density versions. And they can help to flow more air in areas where they aren’t compressed.
There is an excellent thread here on the site about DIY mattresses that you might like to read.
Also, there are some excellent latex component suppliers on this site who provide good advice on latex combinations that tend to work well together.
Thanks for your insight. No, money isn’t tight, I could buy any new mattress I want, but the showrooms around here all remain closed for Covid-19. I don’t want to order a mattress online because you can’t do comparisons that way, and even with a good return policy it’s still a hassle to drag a whole mattress up and down the stairs if I don’t like it. Been there, done that.
So yes, it’s sort of about being a mad scientist since I want something now. My spring unit still seems serviceable and mattress construction doesn’t really look like rocket science to me so I’d like to give it a shot and see how it goes. Anyway, a layer of latex is a lot easier to box up and return than a whole mattress if I don’t like it. I could try that first before buying the cover.
Yes, I did get some advice directly from one of the latex component suppliers but I wanted to hear thoughts on combining latex and foam from someone without an interest in selling me only latex components, since that’s all most of them stock.
Finally, I understand your points about navigating the density and ILD levels of foam. The sellers I looked at don’t offer a vast selection though, so I’d probably end up going with a 1.5 lb polyfoam for the transition layer and an HD36-HQ eggcrate foam by default, topped with 2 inches of soft latex. However based on your reply I’m leaning more toward doing this with a single piece of latex now. That seems like the easiest, most risk-free way to give this a try and if I don’t like it, then I’ll figure out how to choose a whole new mattress during a pandemic.