Plywood Between Mattress and Boxspring – Good or Bad Idea?

Plywood Between Mattress and Boxspring - Good or Bad
Plywood Between Mattress and Boxspring – Good or Bad

We would like to firm up our mattress can you tell us how you feel about a piece of Plywood Between Mattress and Boxspring – Good or Bad Idea? Answer: Not only will we answer that question but a few other commonly asked questions along the same lines.

  1. Does putting plywood between the mattress and boxspring increase support?
    Putting a piece of plywood on a flexible energy absorbing boxspring will not allow the boxspring to give where the body needs it to give.
  2. Does positioning a piece of plywood in between the boxspring and mattress increase mattress life?
    No, especially in the case of flexible boxsprings that can absorb energy that is designed to provide give. If the boxspring does not have the correct give to it the mattress can become squashed and compressed between our body weight and the piece of non giving non-flexible plywood. In the case where the mattress was originally designed for use with a flexible boxspring, use of plywood under the mattress will accelerate wear.

    1. Do doctors / physicians recommend placing a piece of plywood between your mattress and box spring?
      Back in the day this was a common practice for physicians. They believed that placing a board between your mattress and boxspring increased the support for our bodies. At that time the reality was that practice did two things. It increased the speed at which the mattress would wear out while offering some additional temporary firmness for what was usually a worn out mattress. Today my guess is most doctors wouldn’t have a clue as to what impact a piece of plywood would do when used in conjunction with a mattress set. If the doctor did their research they would find that many boxsprings are not boxsprings at all, but are actually foundations that are already rigid just like plywood which of course doesn’t give. Other boxsprings are considered semi flexible, but are just about as rigid as the foundations I just mentioned.
  3. What is the advantage of putting plywood between the boxspring and mattress?
    • This is not our recommendation and really there are not to many advantages.
    • Prolong mattress life by adding some temporary firmness to a mattress that is nearly worn out.
    • It’s cheap and saves you money so you do not have to buy a new mattress set.
    • Won’t have to deal with a mattress salesman.
  4. What is the disadvantage of putting plywood between the boxspring and mattress?
    • Plywood under the mattress can cause the mattress to wear out quicker.
    • Will not let mattress flex and give as it should.
    • You may not get correct support
    • Using plywood may not allow the mattress to breathe properly and the wood can hold moisture even mold.
    • Wood under the mattress can splinter causing the mattress fabric to snag and unravel especially in the case of 2 sided models.
    • A mattress with plywood will not give the same support as a fresh new mattress.
    • Probably not going to help a bad back.
  5. Does laying a piece of plywood between the mattress and boxspring void your warranty?
    Most of the time the answer is yes. You would need to read your warranty card for the specific warranty details. Most warranties are fairly straightforward in that when the mattress and boxsprings are being altered from their intended design say by placing a board between the boxspring and mattress your factory warranty will be void.

NOTE: Just after the turn of the century the mass production of mattresses boxsprings came about. Virtually all boxsprings used coils springs that made them flexible. The coil-designed boxsprings would absorb up to 30 percent of the energy transferred through the mattress. We believed this to be crucial factor to increasing and extending the life of a mattress.

Today with the ever-increasing popularity of thick layers of polyurethane foam, plush, and generously cushioned mattresses, many manufactures claim that the boxsprings are not as affective. By eliminating coil springs in a box spring mattress manufactures were able to decrease costs by decreasing the amount of steel. This is just one of many cost cutting solutions used to help minimize retail costs for the consumer. Another benefit of loosing coiled springs is motion transfer between sleeping partners has been virtually eliminated. None of these advances in the mattress and boxspring over the years has been due to slipping a piece of plywood between them. Our opinion is this: do not use a piece of plywood between your mattress and boxspring it has no real convincing and credible advantages.


Doug Belleville and his father Dave own and run STLBeds - a specialty sleep store located in Arnold, MO. The staff at STLBeds is highly educated about sleep, comfort and their special sleep products. STLBeds only carries high quality mattresses and bed-related products. You won't find the brand names here - just call and ask us why!