Though a mattress should never be so solid that it becomes uncomfortable to sleep on, a firm mattress does provide benefits. A firm mattress offers a solid support structure beneath your body and keeps you from sinking into the mattress, which can lead to back and neck pain. A firm mattress also has a sturdier surface, which doesn’t move as much when someone gets out of bed, which can be advantageous to those sharing a bed.
If your mattress does not feel firm enough, or if you wake up with pain anywhere on your body, you should take steps to enhance the firmness of your mattress. Using a box spring beneath the mattress provides a solid base underneath the bed that prevents it from sagging and can make the mattress itself feel firmer. Make sure to choose a firm box spring to get the sturdiest support from beneath.
A box spring is not the only option for providing support from the underside of the mattress. A platform bed, which generally has a solid wood or plastic surface, provides a flat, firm surface on which to place a mattress directly. Like the box spring, the platform bed prevents the mattress from sinking from below. If you have a bed frame with rails, you can make it like a platform bed by placing plywood between the rails.
If you don’t mind your bed not being elevated, you have a built-in mattress foundation right in your home. Placing a mattress on the floor creates the same rigid support provided by a platform bed if the floor is hard. On softer flooring surfaces, such as carpet, you may want to lay plywood across the floor’s surface beneath the carpet to give it a more solid base.