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How Long Does A Memory Foam Mattress Take To Expand?

The excitement of buying something new and getting your hands on it as soon as you unpack never gets old, no matter how old you are. And if it is an essential and new household item, using your newly bought item is even more exciting, especially if it is a memory mattress.

But with this mattress, you must not lie down or take a nap right after you lay it on the bed. Why? Because this foam mattress takes some time to expand to its original shape, making it impossible to lie on them right after getting it home. But the question is, how long does a memory foam mattress take to expand?

Usually, it takes 6 to 10 hours for a memory foam memory to expand by about 80% to 90%. However, the manufacturer still advises waiting at least 24 hours for the foam to expand fully before use. In some cases, a memory mattress can take more than 48 hours to expand, depending on various factors.

So what are the factors behind the memory mattress’s expansion? What can you do if the foam does not seem to expand? You will find all the answers regarding a memory mattress in this article.

How Long Does A Memory Foam Mattress Take To Expand?

Memory foam mattresses aren’t the same as other mattresses. While other ready mattresses come in expanded form, memory mattresses are shipped folded in a box. As they are deflated before packaging, you will have to give them time to expand.

This unique feature of the mattress allows you to transport it to your home without any hassle. Because manufacturers deflate the entire mattress and fold it into a smaller size before putting it in the box. And that is why some people call the memory mattress a bed or mattress in a box.

But how long does a memory foam mattress take to expand?

The memory foam mattresses expand more in the first few hours, and the rest happens a bit slowly. So, in most cases, a memory foam mattress expands about 80% in 4-6 hours. And after 10 hours, the mattress foam will expand by around 90%.

You may think the mattress has expanded fully after that, but it might not be the case. The manufacturers always suggest waiting at least 24 hours before using it to ensure the mattress has reached its full expansion.

And there is another reason why manufacturers suggest waiting 24 hours. If there is a defect in the mattress, like a crack or split, it will become visible after the mattress expands completely.

That makes it essential to wait for 24 hours at least. Besides, only after that you can understand the quality of the mattress and know if it is worth the money you spend. In some cases, you might have to wait 48-72 hours, depending on environmental factors.

Factors That Affect Memory Foam Mattress Expansion

A memory mattress is made of a material known as viscoelastic. Viscoelastic is very sensitive to heat and density, which helps it shrink and expand based on the temperature it is in. So when you lie down on the mattress, it molds itself into the person’s shape as long as you stay on it. But once you rise, the mattress will automatically expand to retain its original shape.

When the foam mattress is deflated for folding, all its air gets pushed out to make it smaller and fit for the box. But as you unpack the mattress and lay it, the open cells start filling with air, and the mattress expands.

Now, not all memory mattresses will expand fully in the same way or within 24 hours. Some might take even longer, up to 72 hours, because of the factors behind the mattress’s expansion.

A memory mattress expansion depends on various factors, such as temperature, density, thickness, etc. Here are some small explanations that will help you understand how the expansion works.

●      Temperature

Memory foam mattresses are similar to human body cells when it comes to temperature sensitivity. The mattress shrinks in colder environments and expands when the temperature is warm.

That means if you put the mattress in a cold room, it will not expand quickly. No, I’m not saying that the expansion will not happen in such an environment, but it takes a comparatively long time compared to a warmer room.

●      Density

Not all memory foam mattresses are made with the same density. Some have a higher density, while others have a bit low. And the density of the foam is what determines the mattress’s firmness.

It means the more density a foam mattress has, the longer it will take to expand, and it will be firmer. On the other hand, mattresses with a lower density will expand more quickly and are softer.

●      Thickness

The thickness of the foam also plays a vital role in the overall expansion time. How? Well, the thicker a foam mattress is, the longer it takes to expand.

You will find the difference if you compare the mattress with a memory foam pillow. Since the pillows are slightly thicker than the mattress, it takes longer to expand fully. So if you think a thicker mattress isn’t worth the shot, you can opt for a memory foam topper.

What Happens If You Do Not Wait 24 Hours?

So what happens if you can’t wait 24 hours before using the mattress? Will it cause any damage to the mattress or its quality?

The answer is no. It won’t damage the mattress or change anything regarding its quality. In fact, if you sleep on the mattress before 24 hours, you are likely to help expand it quickly with your body’s warmth.

But then the question still stands, why do the manufacturers instruct to wait around 24 hours before using the memory foam mattress? Well, if you don’t wait 24 hours, you will likely experience the following.

  • The first thing you will experience is discomfort. If the mattress hasn’t expanded fully, you will not get the same comfortable night’s sleep that you could have if you waited 24 hours.
  • If there is a defect in the mattress, like a tear or crack, it will become visible only after the mattress expands fully. So if you don’t wait 24 hours, you can’t check for any defect and get back to the seller or manufacturer if you can’t claim the issue within a fixed time.
  • Since the mattress is deflated before packing, unpacking it will release gas as it expands. Though it is not so harmful to most, people with asthma can experience slight discomfort when using the mattress before it expands fully.

Whether or not the mattress will expand in more than 24 hours or earlier varies based on what they are manufactured with. So it is best to follow the manufacturer’s instructions or wait a few more hours than recommended to ensure the mattress’s full expansion.

What If The Memory Foam Mattress Does Not Expand?

You already know that the memory foam mattress takes a few to several hours to expand. So if it’s only been an hour or two and you haven’t seen much difference, do not worry about the mattress. It is not an unusual thing with such a mattress.

However, if it has been a few hours since unpacking and the mattress is still the same or hasn’t expanded much, there is a problem here. Because no matter how slow the expansion of a memory foam mattress is, it recovers at least 70%-90% of its size and shape in 4-8 hours.

If the memory foam does not expand at its usual speed, there is a chance that the mattress is faulty or has a defect. It might have a crack that prevents the air from filling its memory cells.

So the best solution you have here is to call the manufacturer or the seller and let them know about the situation. You must take this step even if you see a small crack that does not seem like a big deal. If you reach out in time, the company may fix the issue or replace the mattress.

Other than that, the mattress might not expand for the following reasons.

  • The most common reason why the mattress is not expanding faster is probably because it has a higher density. Mattresses with a higher density can take as long as 72 hours to expand completely.
  • Is the room cold? If it is, then it might be the reason why the mattress is taking longer to expand.
  • Generally, manufacturers advise unpacking the mattress within 72 after purchasing. If you keep the mattress in the box longer than that, it can take longer to expand.

How To Make Memory Foam Mattress Expansion Faster?

I tend not to believe people who buy something new and interesting and tell me they are not excited about using it. The same thing goes for a memory foam mattress because it is not like a regular foam mattress and has many fantastic characteristics.

So it is natural for anyone to want the foam to expand faster so that they can jump on it and enjoy the feel of a newly purchased mattress. But the problem is, you can’t make the mattress expand fully in an hour or two. However, you can fasten up its expansion by trying the following methods.

●      Unbox It Immediately

You don’t want to wait for several days to unpack your newly bought mattress, do you? No. Take the mattress out of its box immediately after it reaches your home. The sooner you take it out of the box, the better chance it has of expanding more quickly.

●      Unpack The Mattress And Lay It

Once you have taken the mattress out of the box, unpack it, unfold it, and lay it flat. It will expose the mattress’s surface to the air and help fill the cells faster to expand it.

●      Adjust The Room Temperature

Memory mattresses will not expand quickly if you keep it in a cold room. In fact, if the room temperature is too cold, the mattress may not expand at all. So make sure your room temperature is warm enough, such as 68 to 70-degree Fahrenheit.

●      Separate The Layers

Some memory mattresses come in layers because they have multiple colors. The good thing about them is that you can take the layers apart, making it easier to lay them separately and helping them expand sooner than expected.

●      Lie Down On The Mattress

I know I said you could not sleep well on an unexpanded mattress, but that’s for your own good. But lying down on new memory foam will transfer your body temperature to the mattress and make it expand it more quickly.

●      Lay The Mattress On A Hard Floor

Another effective way to expand the memory foam mattress is to lay it on the hard floor after unpacking. The mattress will likely receive a warmer temperature of the room batter from the hard floor and expand faster.

●      Ensure Sufficient Air Circulation

If the weather is good, open the windows and help increase the air circulation of the room. It will help fill the memory cells faster and expand the mattress fully in less hours than instructed. If there is a heater in the room, you can turn it on too.

●      Cover The Mattress With Topper And Sheet

Once you realize most of the mattress has expanded, it is time to prepare it for your bed and a good night’s sleep after the 24-hour is up. After laying the mattress on your bed, make sure to use a topper to cover it. Then cover the mattress with a fitted sheet, and they will keep the mattress less cold.

Frequently Asked Questions

Q. Can you sleep on a new memory foam mattress straight away?

It’s not the best idea to sleep on a memory foam mattress straight after unpacking it because it has a lot to process within the next few hours. So it would be wiser to wait at least 8-12 hours before sleeping on the mattress.

Q. Does sleeping on a memory foam mattress before its full expansion damage it?

There’s no possibility of damaging a memory foam mattress by sleeping on it before its full expansion. However, because the mattress is still partially deflated, sleeping on it before 24 hours can make you uncomfortable.

Q. Why is my memory foam mattress still hard?

Cold temperatures can easily make the memory foam mattress a bit stiff. That is why the mattress can seem hard if the room is cold. Another reason why it feels hard is probably because the mattress is not affected by its surrounding environment’s temperature.

Q. Does heat help memory foam mattresses to expand faster?

Since memory foam mattress is compressed or deflated for packaging, it requires room temperature to expand within 24 hours of unpacking. And the room environment or its heat certainly plays a vital role in its expansion.

Final Words

Memory foam mattresses are getting more and more popular because of the comfort they provide and their efficient portability. So if you plan to get such a mattress, make sure to know the answer to one question. How long does a memory foam mattress take to expand?

And if you have read the article, you now know that depending on several factors, the mattress takes 8 to 12 hours to expand. But for your convenience and the best outcome, it is best to wait at least 24 hours before using it.

Besides, giving the mattress time to expand fully will help you identify if there is any defect and claim a refund or exchange from the seller. Now, I will leave the rest up to you.

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