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Does Plywood Under the Mattress Work for a Soft Mattress?

Does Plywood Under the Mattress Work for a Soft Mattress?

For years, people have been putting plywood beneath their mattresses for various reasons. Whether it is for firming or comfort, several factors come to play to make it a win-win situation.

Putting plywood under the mattress may help in firming your soft mattress. However, overlooking factors like plywood thickness and mattress longevity needs costs you in the long run.

While many may argue that putting plywood under soft mattresses causes more harm than good, this is not entirely true. If done right, it could save you money and sleepless nights.

check under bed

Advantages of Using Plywood under a Soft Mattress

Using plywood under your soft mattress comes with the following advantages:

Firming your Soft Mattress

Plywood firm your soft mattress. The downsides of using a soft mattress include having an uncomfortable sleep and waking up with lower back pains. While you can overlook these in the beginner stages, continuous strain and discomfort can lead to posture issues.

By reinforcing your soft mattress, plywood lengthens its life. You get a better night's sleep and overall better health.


Plywood is relatively cheaper than box spring or even mattress padding. You get to save money while improving the quality of your sleep.


Unlike the traditional box spring, plywood lets you decide on your assortment's dimensions. If you have a distinctive bed size and design, plywood provides firming suited to your needs. Moreover, if you want to reinforce your bed's height, eliminate some and vice versa.

More Storage Space

There is more space underneath the bed when using plywood, giving for extra storage.

Disadvantages of Using Plywood under a Soft Mattress

Some downsides to using plywood under the soft mattress include the following;

Plywood Lowers the Lifespan of your Mattress

Plywood compromises the breathability of the mattress as air is unable to move freely. The mattress then forms a suitable breeding zone for mold to start eating into it. It wears away faster than it could if box springs were in place.

Less comfortable

After some time, the plywood may begin to warp, forcing you to start sleeping in awkward angles. In addition, when the wood splinters, the splinters tend to undo your mattress' fabric. Since the edges are uncomfortable, you have troublesome naps or sleep sessions.

Plywood is not suitable for people with special conditions such as arthritis since it fails to provide the support that box spring does.

Needs Experimenting

Hacking the sweet spot between stiffness and comfort will take some experimenting. In your initial times, you may compromise your comfort for stiffness. It occurs when you make the plywood stack too thick; over 1.5 inches high.

Factors to Consider When Deciding on Plywood beneath a Soft Mattress

Before you try devising a quick-fix solution for your soft or saggy mattress, consider looking at the following factors:

Body and Mattress Weight

The secret to getting the best plywood dimensions is to know the weight of the person or people going to be sleeping on it. In addition, determining the weight of your soft mattress will help you pick the right thickness.

One should use plywood of at least three-quarters of an inch. Any sizing thinner than that will be considered weaker. In return, you fail to properly reinforce your mattress and end up with the very problems, if not more.

The Issue You want to Tackle

In most cases, people with soft or saggy mattresses fail to determine their pain points. Whether mattress sagging, gaps, or old age, highlighting this sets the ground.

For instance, specific parts of your soft mattress could require reinforcement. You will get plywood for specific, measured areas and not the entire mattress. In addition, you can customize the height of the plywood to achieve the desired prop.

If old age is the cause of the softness, use plywood on the entire area beneath your mattress. However, remember that plywood sizing is crucial. Go for three-quarters of an inch thickness or more.

The Required Hardness

Plywood is an easy and reliable solution to making your mattress firmer. Yet, failing to determine the exact hardness level could lead to distasteful outcomes.

For an okay hardness level, you should go for at least 19 millimeters in thickness. On the higher side, go for 40 millimeters. However, the amount of stiffness you require determines the exact dimension.

Some people may want to double its height since two or more people sleep on the bed. It is wrong as the bed itself already has weight.

However soft you want your mattress to be, please do not go below 19 millimeters in thickness. Yet, any thickness under 19 millimeters counts as too weak a support.

The Health Conditions of the User

Truth is, plywood is unable to deliver the level of coziness and support that a new mattress does. It also does not have the springy effect that a box spring gives.

If you have special health conditions such as arthritis, spinal injury, or hip bone dislocation, you need a keener eye. For cases such as arthritis, if you need leg alleviation, talk to a plywood specialist. Let them design plywood dimensions that will not only solve the leg problem but give you the desired comfort.

For spinal injury, the best solution is to have no dips in your mattress. Still, it has to be comfy to sleep on as stiffness may awaken the pain. The good thing is that plywood is greatly customizable, making it a great pick for your unique needs.

Mattress Warranty

Unbeknownst to many, altering your mattress may cost your warranty. Most dealers are keen on specifying that changing the original design of your mattress will lead them to overlook the warranty.

Since plywood diminishes the lifetime of your mattress, anyone who wants to use their mattress warranty may steer away. As soon as the breathability is compromised and molds get in, then you have to forget about your warranty.

To avoid this, please check your mattress warranty before using plywood underneath it. You will find the precise specifics and guidelines that could save you in the future.

base wood hand

What Type of Plywood Should You Use Under Your Soft Mattress?

When picking plywood to be used under your bed, opt for one with birch plywood at the core. While MDF or Particleboard cores may still work, they do not offer the same core strength. Here are viable options for when you want to use plywood for under-mattress;

Veneered Birch Plywood

Made by banding thin raw birch sheets, the veneered birch plywood offers better resistance to depreciation than ordinary plywood. These also offer flexibility in look as they are easy to design and customize.

Club Prime

Club prime is known for its watertight plywood. Made using pre-pressed plies which are more than the average number, club prime offers more firmness and permanence.

Architect Ply

The Architect Ply is made by bonding hardwood with the synthetic resin of boiling waterproof grade. In most cases, it offers proof to termites and borers, adding to its durability and functionality.


Decoply gives you the option of having a colored option for your plywood. It comprises a high-laminate hard-pressed on birch plywood. The outcome is then painted to suit your color palette.


Plywood is a great solution for reinforcing your soft mattress as it is cheaper and easy to customize. However, it is best suited for temporary use since its lack of breathability can damage your mattress. All in all, noting these caveats will have you get the best from your plywood.

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