Buying a child’s first proper bed throws up questions nobody warns you about. How high should the rail be. Is that gap too big. What does the label on the base actually mean. And underneath all of it, the one that keeps parents awake: is this thing safe?
We build kids beds in West Yorkshire, so we deal with these questions every week. This guide covers what genuinely matters, what the law requires, and which bits of advice you can safely ignore.
One thing up front. A lot of articles on this topic quote precise millimetre figures for safety rails. Check three of them and you will get three different numbers. We have explained why below, and what to ask for instead.
When to move from a cot to a bed
Most children make the switch somewhere between 18 months and three and a half years. There is no correct age, and rushing it helps nobody.
Move them when you see these signs:
- They climb out of the cot, or try to
- Their shoulders reach close to the cot sides when they sit up
- They stay dry overnight and need to get to the toilet
- A new baby needs the cot
Hold off if your child still sleeps restlessly and rolls a lot, or if the bedroom has hazards you have not sorted yet. A cot that still works is safer than a bed they are not ready for.
Choosing a bed by age
18 months to 3 years
Go as low as you can. At this age children roll, and the drop matters more than anything else. Look for:
- A low bed height
- A safety rail on any exposed side
- No sharp corners or hard edges
- Upholstered sides rather than bare timber
Our kids beds with safety rails sit low and use padded upholstery all round, which suits this age better than a standard frame does.
3 to 6 years
Most children in this bracket sleep in a standard single. Keep the rail on for the first year or so, then take it off once they stop rolling into it.
This is also the age when storage starts to earn its place. A kids bed with drawers absorbs the toys and clothing that would otherwise need a separate unit, which frees up floor space in a small bedroom.
6 and over
From six upwards, children can use a bunk bed or high sleeper. Below six, they should not sleep on a top bunk. That guidance is consistent across UK safety bodies and it is the one age rule worth treating as firm.
Older children can also handle a bed with lift-up storage. Our kids ottoman beds use the same gas strut mechanism as our adult range, so a younger child will not be able to work it alone. That is deliberate.
How safety rails actually work
A rail does one job. It stops a sleeping child rolling off the edge.
That sounds obvious, but it explains why rail height on its own tells you very little. What matters is the height of the rail above the mattress surface, not above the bed base. Fit a deeper mattress and the effective rail height shrinks. Fit one deep enough and the rail stops working entirely.
Why we are not quoting exact figures
Search this topic and you will find guardrail heights quoted as 16cm on one site and 13cm on another, with gap limits ranging from 7.5cm to 30cm depending on who you read.
Those numbers come from BS EN 747, which is the standard for bunk beds and high sleepers. It sets requirements for beds where a child sleeps at height. It does not apply to a low single bed with a side rail, which is what most parents are actually buying.
So quoting bunk bed figures at you would be misleading. Instead, ask the retailer two direct questions:
- Which standard does this bed meet, and can you show me the declaration?
- What is the maximum mattress depth for the rail to work as designed?
Any manufacturer who builds beds properly can answer both in a sentence. If they cannot, that tells you something.
What to check on any rail
- It fixes to the frame. A rail that slots in loosely can be dislodged by a child pushing against it.
- It runs the length of the sleeping area. A short rail in the middle leaves gaps at the head and foot.
- There is no gap between rail and mattress. This is the entrapment risk, and it is the one that causes real harm.
- The bolts stay tight. Check them monthly. Timber moves, fixings work loose.
Mattress fit matters more than the rail
This is the point most guides bury, and it deserves to be near the top.
A mattress that does not fill the frame leaves a gap along the edge. A child can slip a limb into that gap, or roll into it and end up wedged between mattress and rail. The rail is doing its job. The gap is the hazard.
Two rules:
- The mattress should sit snug against the frame on all sides. If you can push your hand down the edge easily, it is too small.
- Do not exceed the maximum depth the bed was designed for. Every centimetre of extra mattress lowers your effective rail height.
Buy the bed and mattress together where you can. Our mattress range lists depths, and we match sizes when you order both from us.
Fire regulations explained
Every bed sold new in the UK has to meet fire safety law. Here is what that actually covers, without the jargon.
What the law requires
Two things apply to a child’s bed:
- The Furniture and Furnishings (Fire) (Safety) Regulations 1988, amended several times since, most recently in 2025. These govern the fillings and covers used in upholstered furniture.
- BS 7177, the standard covering resistance to ignition for mattresses, mattress pads, divans and bed bases. For a bed in a family home, the product needs to pass the Low Hazard rating, which tests it against a lit cigarette and a lit match.
Upholstered bed bases count here too. A base built from timber, fabric and foam burns, so it has to meet the same level as the mattress.
Where to find the label
Look on the base itself, usually on the underside or along one side, and on the mattress.
A valid label prints clearly with legible manufacturer details and the relevant standard. Treat these as warning signs:
- Handwriting anywhere on the label
- Faded or illegible text
- No manufacturer name
- No label at all on a bed sold as new
Headboards work differently
Worth knowing, because it catches people out. Mattresses, divans and bed bases do not need the permanent label that other upholstered furniture carries, because BS 7177 covers them separately.
Headboards do. A headboard counts as upholstered furniture in its own right, and both faces of the fabric have to be tested, not just the side you can see.
Every bed we build gets tested and labelled to these requirements before it leaves the workshop.
Bunk beds and high sleepers
We do not build bunk beds, so treat this section as general guidance rather than a sales pitch.
If you are buying one:
- Check it states compliance with BS EN 747 and ask to see the declaration
- Use only a mattress within the depth the manufacturer specifies, since a deep mattress defeats the guardrail
- Keep under-sixes off the top bunk
- One child on the top bunk at a time
- Assemble it exactly as instructed, with no modifications
- Position it away from windows, radiators and light fittings
Most bunk bed accidents trace back to assembly errors and loose fixings rather than the design itself. Build it properly, then check the bolts every month.
Buying second-hand
We understand why people do it, and we would still say be careful.
An older bed may predate current standards, and years of use loosen joints in ways you cannot always see. Fire labels also matter legally: second-hand furniture sold in the UK still needs a permanent label.
If you do buy used:
- Check for a fire label and read it
- Test every joint and fixing before a child sleeps in it
- Get the full assembly instructions
- Skip it entirely if the frame flexes or creaks under weight
Where to put the bed
Room layout prevents more accidents than any bed feature does.
- Keep the bed away from windows, and fit window restrictors regardless
- Leave clear space around radiators
- Nothing hanging above the bed
- Blind and curtain cords tied high and out of reach
- Rugs with a non-slip backing, or no rug beside the bed at all
- A soft landing beside the bed for the first few months after the switch
Monthly checks
Five minutes, once a month.
- Tighten every bolt and fixing
- Check the rail sits firm with no movement
- Push down the mattress edges and look for gaps
- Run a hand over the frame for splinters or cracks
- Check slats sit properly in their supports
FAQs
What age can a child sleep in a bed?
Most children move from a cot between 18 months and three and a half years. Go by readiness rather than age. Climbing out of the cot is the clearest signal.
Do kids beds need safety rails?
Not by law, but they help for the first year or two after the move from a cot. Fit rails on any exposed side while your child still rolls in their sleep.
How high should a bed safety rail be?
Measure from the mattress surface, not the base. Ask the manufacturer for the maximum mattress depth their rail is designed for, because a deeper mattress reduces the effective height.
At what age can a child use a bunk bed?
Six and over for the top bunk. UK safety guidance is consistent on this and it is worth following strictly.
What fire safety rules apply to children’s beds in the UK?
The Furniture and Furnishings (Fire) (Safety) Regulations 1988, as amended, cover fillings and covers. BS 7177 covers ignition resistance for mattresses and bed bases, and a domestic bed should meet the Low Hazard rating.
Where is the fire label on a bed?
On the base, usually underneath or along one side, and on the mattress. Handwritten, faded or missing labels on a new bed are a warning sign.
Are ottoman beds safe for children?
For older children, yes. The gas strut mechanism needs adult strength to operate, so a young child cannot lift it alone. Keep under-sixes away from the mechanism.
Can I use a second-hand bed for my child?
You can, but check it carefully. Look for a fire label, test every joint, and get the assembly instructions. Older beds may not meet current standards.
What mattress depth suits a kids bed with rails?
Whatever the bed maker specifies. Exceed it and the rail sits too low relative to the mattress to work properly.
Talk to us about your child’s bed
Every JMH bed gets built to order in West Yorkshire and tested to UK fire safety requirements before it ships. Tell us your child’s age and your room size and we will tell you which setup suits.
Browse kids beds with safety rails
Need storage as well? Compare our kids beds with drawers against the ottoman storage range, or get in touch if you want a hand choosing.