How to firm up a soft mattress

Updated

January 9, 2024

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Do you have a plush bed, or is the support deteriorating over time? In this guide, we will show you how to firm up your soft mattress and also cover:

  • How to deal with a soft mattress
  • How to make a mattress more comfortable 
  • How to make a spring mattress firmer 
  • A method of making pillow-top mattresses firmer 


To firm up a soft mattress, you can replace your bed's foundation if needed. You can also add a topper and a bamboo topper for extra firmness. Monitoring your room temperature also helps firm your soft mattress. 

Found yourself in a mattress too soft. How to make a firmer situation? Well, fix your mattress blues for nights of undisturbed, adequate sleep.

How to make mattress firm

Is your soft sleeping surface disrupting your slumber time and giving you body-aches? Or has your mattress sunken so low that you desperately need firm support? There could be many reasons behind your mattress sinking with specific solutions. 

Naturally, you might be confused about how to harden a soft mattress.

According to the Sleep Foundation, all mattresses eventually sag, but there are ways of firming them up and slowing the sinking process. You have to know which type of mattress you use and also consider the severity of the sag.   

We have gathered vital solutions below on how to harden a soft mattress.

What to do if your mattress is too soft

Are you troubled by the mattress softness every time you hop onto the bed after a flat out day? For some double-sided mattresses, one can simply flip the mattress. However, there are a wide variety of mattresses that requires varying firming techniques.

While some remedies require significant effort, if you're one of the lucky few, all that's needed is to stay calm, stay calm or find a plywood board. Check out these methods:

Use a mattress topper

It is possible to add additional contouring or pressure relief to a too-firm mattress by adding a mattress topper. It's by far the simplest and most effective way to firm up a mattress.

Mattress toppers can soften surfaces, however, materials like firm latex and compact wool can slightly improve firmness or at the very least improve supportiveness. However, avoid softer foams and fibers. Discover a few different options in our mattress topper review.

Find a solid base

If you have a slatted base, you can sandwich a plywood board between your bed's base and mattress. The tricky part is cutting the plywood sheet to match the size of your foundation. If fitted correctly, the plywood board may prevent further mattress sinking as it checks the gaps between the slats. 

You can try this hack rather than using a box spring if you use a soft foam mattress. 

You can also use other foundational platforms to harden your plush bed surface. Your mattress' softness can also occur due to the overall faulty foundation of the bed. Try investing in a new foundation as old ones tend to weaken and wear out as the clock ticks. 

How to make the mattress more comfortable

To ensure a comfortable, undisrupted sleep, try periodic mattress rotation. Swapping the head and foot of a mattress is a simple remedy to maintain pressure. Rotating your sleeping surface once in a few months might keep your bed free from soft, sagging spots for a more extended period. 

Based on the type of mattress, you can rotate to 180 degrees twice to five times a year.

Rotating your mattress after specific intervals balance out the softened areas due to disproportionate body weight distribution. 

How to make spring mattress firmer

With time, metal coils in traditional spring mattresses lose tension, softening the surface. Well, you don't have to replace your mattress entirely. Instead, try switching to a firm mattress topper.  

Sometimes, maybe the problem lies in your bed's support structure. Just check your box spring. It gives added support to your bed, but box springs can lose their sturdiness over time.  A new box spring might give you the desired support and firmness.

How to make a pillow top mattress firmer

A Pillow top mattress comes with an added layer of padding for a more plush feel. However, with time, maybe you'd want to experience firmer support. Here are some hacks you can try:

  • Removing the old box spring. 
  • Inspect your bed frame and fix all the loose screws. Check and adjust the frames alignment as well. 
  • You can also place a foam pad atop the mattress.
  • Choose a top pillow mattress with more springs and less spring gauge.

How to firm up a Tempurpedic mattress

Looking for ways to experience a firm slumber on the soft layers of your Tempurpedic mattress? You can go for added hardness by placing a latex or compact wool topper. 

A topper is a separate layer that helps you with additional firmness or softness. For example, it might have a thickness between 2 to 5 inches. Such layers that specialise in firmness offer some resistance and solidify your bedding. 

Choosing the right sturdy topper might be your problem solver if you are going low with your budget. 

It's a wrap

In summary, adjusting your soft mattress' firmness is easier than you thought it would be. Trying out the given techniques instead of buying a new mattress could save you money. 

If you want to adjust the firmness of your mattress, keep in mind that every mattress type requires a different method. However, we went over a few different ways to help make your soft mattress firmer.