A trundle bed is a single bed with a second pull-out mattress stored underneath, making it one of the most space-efficient sleep solutions for sleepovers and shared kids' rooms in Australia. For families juggling cousins staying over, siblings sharing a room, or a child moving from cot to a bigger bed, a trundle solves two problems at once.
It gives you a second sleeping surface when you need it, then gives the floor space back the next morning. This guide explains how trundle beds work, which families they suit best, what mattress sizing to check, and the safety points Australian parents should understand before buying.
What a Trundle Bed Is and How It Works?
A trundle bed consists of a main bed frame, usually a single bed, with a second low-profile bed frame stored underneath on castors. The lower frame rolls out when a second sleeper needs a bed, then rolls back under the main bed during the day. That is what makes it useful in kids' rooms where floor space matters.
Most Australian trundle beds are designed around single sleep surfaces, but the mattress height needs careful checking before purchase. The lower mattress usually needs a slimmer profile so it can slide under the main bed without catching. Many trundle mattresses need to stay under 15cm high, although the final measurement depends on the exact frame.
There are two main styles: pop-up trundles and flat trundles. A pop-up trundle raises the lower bed closer to the main mattress height, so both sleepers feel more even. A flat trundle stays close to the floor and is usually better for occasional sleepovers.
For parents comparing bed types, Boori's explore all kids' beds range is a useful starting point because it shows how single, bunk, loft and trundle options fit different rooms and stages.
Who Trundle Beds are Best for: and When They Make Sense?
A kids trundle bed makes the most sense when a family needs a spare bed sometimes, but not every night. Sleepovers are the obvious example. Instead of storing a folding mattress or blowing up an inflatable bed, the spare sleep space is already built into the room. You pull it out, make it up, then push it away in the morning.
Trundle beds can also help in shared bedrooms, especially in smaller Australian homes and apartments. When two children share a room but the second bed does not need to stay open all day, the trundle helps protect play space, study space and storage access.
They also suit transitional stages. A child who has outgrown the cot may need a proper bed, while the family may still want flexibility for guests, cousins or a younger sibling later. A trundle bed for kids gives that flexibility without committing to a permanent second frame.
Storage still matters around the bed. If a trundle takes up the under-bed space, you may need shelves, drawers or baskets elsewhere. Boori's add storage to your kids' room collection can help keep bedding, toys and clothes organised without crowding the sleep area.
Sizing, Mattress Fit and What to Check Before Buying
Australian standard single mattresses usually measure 92cm × 188cm, and most trundle beds are designed around single-size mattresses for both the main bed and the lower trundle. That measurement should be checked before buying because some trundle frames have their own clearance limits, especially underneath the main frame.
The mattress height for the trundle level is the detail parents often miss. Measure from the floor to the underside of the main bed frame, then allow enough clearance for the trundle frame, mattress and bedding. If the mattress is too tall, it may not slide away neatly. Many lower trundle mattresses need to stay under 15cm high.
Room clearance matters just as much as bed size. When the trundle is pulled out, it usually extends about 90cm beyond the main bed frame. A practical room plan should leave clear floor space on one side, so the bed can open fully without hitting wardrobes, desks or toy storage.
King single trundle setups also exist, usually with a king single main bed and single trundle below. These can work well for older children who need extra length on the main bed but still want the sleepover option. Boori's find the right mattress for your trundle bed collection includes kids' mattress options that help parents compare size, support and fit before finalising the setup.
Safety Considerations and Australian Standards for Trundle Beds
Trundle beds are generally not recommended as a primary sleep surface for children under 3. The lower bed is close to the floor and open on the sides, so it suits children who have better rolling awareness and can manage the bed edge safely. For many families, that means using the trundle level for children aged 3 and above.
For children aged 3--6, the trundle should be set up carefully. Use a fitted sheet that stays secure, keep the floor clear around the pull-out bed, and consider a low-profile guard rail if the child is a restless sleeper. The second bed should feel like a proper sleep surface, not a temporary mattress placed wherever it fits.
Castor quality also matters. The trundle frame should roll smoothly, then lock securely when in use. This is especially important on hard floors, where movement is more likely if the wheels do not hold well.
Australian parents should check that the chosen frame meets relevant AS/NZS furniture safety standards and that the lower mattress is firm and flat. Avoid adding memory foam toppers for younger children because they can create a softer sleep surface than needed. Families who want to compare options in person can see trundle beds in person at a Boori showroom before deciding.
FAQ
Is a trundle bed safe for a toddler?
A trundle bed is generally not recommended as a primary sleep surface for children under 3 because the lower level is open-sided and close to the floor. For children aged 3 and above, it can work when the mattress is firm, the sheet fits securely, and the floor area stays clear.
Can a trundle bed fit a queen mattress underneath?
A trundle bed cannot fit a queen mattress underneath because most trundle frames are made for a standard single mattress. The lower frame is limited by width, castor height and under-bed clearance, so a queen mattress is too wide and too thick for normal trundle storage.
What is the difference between a pop-up trundle and a flat trundle?
A pop-up trundle raises the lower bed closer to the height of the main mattress, which makes it better for regular use. A flat trundle stays low to the floor and usually suits occasional sleepovers. Boori recommends checking the frame type before buying because the two formats feel different.
Trundle bed vs bunk bed --- which is better for two kids sharing a room?
A bunk bed is usually better when two children sleep in the same room every night because it saves floor space permanently. A trundle bed is better when the second sleeping surface is occasional, such as for sleepovers or visiting cousins, because the floor space returns during the day.
What mattress thickness do I need for a trundle bed?
A trundle mattress usually needs to be under 15cm high so it can slide beneath the main bed frame with clearance. Parents should measure the gap before buying, because bedding and the trundle frame also take up space. Boori's kids' mattresses include options for different bed types and sizes.
Can a trundle bed be used as two separate beds?
Most trundle beds are designed to tuck underneath the main bed and are not intended to stand alone as a separate bed frame. Some pop-up models may work independently, but this depends on the exact design. Boori recommends checking product details before assuming the trundle can be used separately.
What size room do I need for a trundle bed?
A trundle bed needs enough space for the main single bed footprint plus about 90--100cm of clear floor space on one side. A room width of around 3 metres is a practical minimum for easy pull-out use. Always check wardrobes, drawers and door swings before ordering.
Summary
A trundle bed is a smart sleep solution for Australian families who want a second bed on demand without the permanent floor space of a bunk bed. It works best when the mattress fits properly, the castors lock securely and the room has enough side clearance. Explore Boori's explore all kids' beds range online, or visit the South Wharf Melbourne showroom to see trundle options in person.
