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What Are Bed Frame Slats?
Bed Frame Slats
Bed frame slats are what a mattress sits on, and they can also change how a mattress feels depending on how much flex they have.
Without slats, a mattress wouldn’t have anything to sit on, and it would fall straight through the bed as soon as you get on it.
Some slats are straight, while others have a curve that lets them flex under load, creating a cushioning sensation with more bounce.
This article covers everything you need to know about bed slats and tips for choosing the right type for your mattress.
Let’s jump in!
What are bed frame slats?
Bed frame slats are wooden planks that you arrange in a parallel series across the width of a bed frame to make a mattress platform.
Wooden slats are lighter and easier to package and transport than solid bed bases, so they are more popular with standard frames.
Why does a bed need slats?
A bed lifted off the ground needs slats so the mattress can rest on something. Without them, the mattress would fall through.
Every mattress needs a firm base, and slats are more forgiving than solid platforms because they put less pressure on the mattress’s inner components. This improves the feel of the mattress and can make it last longer.
Slat types
Bed frame slats come in two types:
- Straight (no flex)
- Sprung (with flex)
While most people pay no attention to whether slats are straight or sprung, it’s essential to know that they can make mattresses feel different.
![Sprung Bed Frame Slats.](https://www.bedstar.co.uk/wp-content/uploads/2021/07/spung-slat.png)
Here’s how:
Straight slats provide minimal pressure relief, making the mattress do all the work for cushioning and bounce. Sprung slats bend and flex when you move around, so they work with the mattress to provide cushioning.
For these reasons, sprung slats are better for thinner mattresses, while straight slats are better for thick mattresses with better support systems.
What wood is used for wood slats?
Manufacturers specify pine or birch for wooden bed frame slats because they are cheap, renewable, and durable.
While some beds have red or white oak, hickory, or ash slats, there is no practical advantage, and most beds use pine or birch.
How thick should bed slats be?
Bed frame slats come in the following standard sizes - 1x3”, 1x4”, 1x5”, or 1x6”. This means they are 1” thick and 2ft, 4ft, 5ft, or 6ft wide.
However, after milling, the slats are usually about 3/4” thick. This is more than sufficient for heavy people, and wide, heavy mattresses providing the slats are made from solid, flexible wood like pine or birch.
However, you should avoid jumping on your bed because the small surface area of your feet, plus your body weight, can crack the slats.
How much weight do bed slats hold?
![Sleeping positions.](https://www.bedstar.co.uk/wp-content/uploads/2022/09/sleeping-positions.jpg)
Most bed frame manufacturers rate their slats for 300 to 400 lbs when spread across the bed, meaning two 200lb people can sleep on them.
However, some slats are rated to hold no more than 300 lbs, typical for single and small single (toddler) beds. If you and your partner weigh more than 300 lbs combined, verify the manufacturer’s weight limit before purchasing.
Slats vs. solid base
The alternative to bed frame slats is a solid platform such as that provided by a divan base or a metal bed with a wire rack platform.
Slats are lighter, cheaper, and replaceable, while solid bases are heavy-duty. However, the critical difference is how they affect how a mattress feels.
While even straight slats provide some pressure relief on a mattress’s inner components, solid bases provide no pressure relief. They are reliable and robust – so they are better for thick mattresses (over 30cm).
If you try a mattress under 30cm thick on a solid platform and then on sprung slats, the difference is clear – the mattress feels softer on slats every time.