Friday, January 25, 2013

Our Foam Mattress - The Comfort Layer(s)

foam mattress - support layers
Foam mattress - (no cover)
***Updated 1/20/15:***
This is the sixth post in the series about building our latex foam bed. Be sure to look over earlier posts with more details about how the bed was built. In order they are "Decision", "Foams", "Suppliers", "Advantages", "Foundation" and "Mattress".

The final task is to construct the comfort layer(s), which in a conventional bed would be called the "mattress". These layers provide the soft, supportive surface on which we sleep and these are the layers that can be adjusted for individual preference.

In a foam bed the comfort layer is built from individual layers of polyurethane foam, latex foam, and/or memory foam whereas In an innerspring conventional bed the mattress is often made from metal springs sandwiched between thin layers of some type of foam. Even expensive innerspring mattresses are no match in terms of comfort for the foam mattresses. Once you decide to abandon the lumpy, squeaky innerspring the only choice is the type of foam to use.

We decided to encase our latex comfort layers in a zippered cover. A conventional mattress pad is fitted on top of the stack (see photo below) to pull everything together.

Complete with covers and pad
Final Configuration:

The completed bed is now 15" of foam. Starting at the bottom, just above the wooded slats, we have 7" of relatively firm (HD Lux-HQ) polyurethane (the "boxspring" of a conventional bed) - this is the blue foam in the previous articles. Then 3" of medium firm HR polyurethane, the transition layer, sometimes called a support layer, between the firm foundation foam and the softer comfort layers. Then 3" of medium firm Talalay latex foam; and 2" of soft Dunlop latex foam (the comfort layers). If desired the latex foam layers (5" total) could be replaced with memory foam, at around $400-$500, converting the bed to a high quality memory foam bed that might otherwise retail for $3,000+.

Final Thoughts

Our perfect foam bed is now about 3 years old and is performing wonderfully. It is very comfortable for both of us, does not squeak or creak and is fairly easy to move. Total cost, not including hardwood frame, bedding and pillows, is $1,008, a whole $8 over budget!. The cost breakdown is: 7" HD Lux-HQ ($228), 3" HR ($230), 3" Talalay Latex - medium ($273), 2" Dunlop Latex - soft ($237) and wood slats ($40).

One of the unexpected advantages of our foam bed is that it is adjustable, not in the push-button sense of air beds but by swapping out individual layers, or rearranging the different firmness layers, you can adjust the firmness of the final sleeping surface. And, if we decide we like memory foam at some point in the future we can have a memory foam bed by adding an inexpensive 2"-3" memory foam topper to the already excellent foundation and comfort layers.

One thing I have learned, however, is that latex foam is very dense and heavy. Since we rotate the comfort layers every 3 months or so this weight has become noticeable. If the relatively heavy latex layers are an issue for you consider using soft HR polyurethane rather than latex for the top comfort layers. Polyurethane is much lighter and the HR types will impart most of the "springiness" of latex.