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Do you feel like your baby is too big for his or her crib?

If the answer to that question is yes, then it might be time to start lowering the mattress. Larger babies can outgrow their cribs quickly and may find themselves with little room left in the bed. It may also become unsafe for them as they are able to climb or roll over more easily than when they were smaller.

Lowering the mattress on a crib will give your child more space without taking away from the safety features of the crib itself. So, when can you lower the crib?

When to Lower Crib

You can lower the crib when your baby is around age 2 to 3 years or as soon as your baby is either rolling over or trying to climb. It’s important that you take into consideration that the child can get in and out of the crib safely when making this decision, otherwise it might not be wise to lower it. Whether you have a big crib or a mini-size for small spaces such as apartments, most cribs need to be lowered at some point to ensure they are safe for kids.

If your baby is standing in the crib, then there are no safety concerns with continuing to use the crib. You can lower the crib once your baby is standing and then continue to use it until he or she climbs over the side of the crib.

Once your baby reaches six months old, you should not be using a crib with a mesh exposed because there is too high of a chance that he/she will suffocate in the mesh. If you have a mesh-side crib, you can switch it to a regular crib once your baby begins standing up or trying to climb.

AAP Crib Height Recommendations

The American Academy of Pediatrics recommends a crib with a low enough mattress for your baby to be able to roll over without getting caught. AAP recommends that from age 2 to age 3, you should adjust your baby’s crib mattress height and lower it as the baby grows. AAP recommends that your baby should transition out of the crib by the time they attain 35 inches in height. They also recommend that the crib mattress should be no less than 26 inches below the side rail and advice against using a walled crib when they’ve attained that height.

They also suggest using a firm mattress and not a pillow, blanket or bumpers as these can increase the chances that your baby will suffocate. In a study by AAP, more than 7,900 babies end up in ER because of injuries related to cribs.

When should I lower the crib mattress?

Once your baby is pulling himself/herself up, you can lower the crib mattress to 24 inches.

After your baby is standing with assistance, then you should lower the mattress to 18 inches.

When your baby is about 20 to 40 months old or can climb out of the crib on his/her own, it’s time to still lower the crib or start thinking about purchasing a toddler bed that fits the space and has a low enough space for the baby to escape.

The best way to lower the crib is by using an adjustable rail kit which will allow you to lower the rails at any point along its length. Follow these steps below:

  • 1) Clean off all surfaces on the crib and make sure that there is no dust or grime on it. You don’t want to lower the rail and then get dirt all over your baby’s skin.
  • 2) Look at where you will need to attach the rail and figure out how many sections of rails you will need to use in order to reach the new height needed.
  • 3) Using a Phillips-head screwdriver, adjust the height of the crib rail to the new height needed until it’s firmly attached. You may want to consider fastening that rail at one foot intervals so that you can continue to lower the crib gradually as your child grows. Once it is securely attached, make sure there are no gaps between the new height and the floor.
  • 4) Lowering the crib gradually will prevent your child from being surprised by a sudden change in height. However, if you’ve lowered it too much, your baby might experience hip problems or other discomforts because his/her legs are forced into different positions than they’re used to.
  • 5) Make sure to store all parts of the old rail safety so that they do not fall on your child.

How to lower the crib

What about the mattress height?

The AAP suggests that you lower your baby’s crib mattress height as he or she grows until it is low enough for them to roll over onto their stomachs without getting caught underneath it.

Follow these steps below to know when your baby can climb out of the crib.

  • 1) Once your baby is able to pull himself/herself up, lower the mattress height down to 24 inches. You should do this after they are strong enough that they can support themselves for a couple of minutes.
  • 2) Lower the mattress once your baby starts to stand with assistance. Lower it to 18 inches.
  • 3) Once your baby is about 30 months old or taller, he/she should transition into a bed that has low rails and fits the size of his/her bedroom.