How Do You Measure Your Bed Frame to Make Sure a Mattress Will Fit Properly?
Finding the right mattress means considering more than your preferred firmness or cushioning. If your mattress doesn't fit its bed frame correctly, you could end up with uncomfortable gaps, restricted movement or an unstable sleeping surface.
Although standard UK mattress sizes make shopping more straightforward, bed frames can vary considerably in their construction. Measuring the space where your mattress actually sits is therefore essential, particularly if you're replacing an older mattress or keeping an existing frame.
Why Should You Measure Your Bed Frame?
A bed frame's advertised size doesn't always tell you everything about the space available for your mattress. While standard frames are generally designed for particular mattress dimensions, the external measurements can be much larger than the sleeping area.
For example, an upholstered king size bed may have a wide headboard and substantial padded sides, but the mattress itself should still match the frame's intended sleeping dimensions.
Measuring helps confirm compatibility before ordering. It also prevents confusion between the frame's overall footprint and the internal area designed to support the mattress.
How Do You Measure the Internal Width?
Start by measuring the distance between the inside edges of the frame's side rails. Position your tape measure across the area where the mattress will sit rather than across the outside of the furniture. Take measurements near the head, middle and foot of the frame, particularly if it's older or has been moved several times. If the measurements differ noticeably, inspect the frame for loose fittings or structural problems.
Write down your results in centimetres and compare them with standard mattress dimensions. This provides a more reliable indication of compatibility than relying on the bed's original name or appearance.
How Do You Measure the Internal Length?
Measure the usable distance between the head and foot of the mattress platform. If your frame has a substantial headboard or footboard, make sure you're measuring the internal sleeping area rather than the decorative outer structure.
UK single and double mattresses normally measure 190cm long, while king and super king mattresses measure 200cm. That 10cm difference is important when replacing an existing mattress.
A frame designed for a standard double won't necessarily accommodate a king mattress, even if the widths appear relatively similar. Always check both measurements before deciding on a size.
What Are the Standard UK Mattress Sizes?
We offer mattresses in standard UK dimensions, making it straightforward to identify a suitable size once you've measured your frame.
A single mattress measures 90cm by 190cm, while a small double measures 120cm by 190cm. A standard double is 135cm by 190cm, and a king measures 150cm by 200cm.
For larger bedrooms, a super king measures 180cm by 200cm. These dimensions refer to the mattress itself, so the complete bed frame may require additional floor space.
Some of our mattress models are also available in European sizes. Always check the precise dimensions rather than assuming UK and European size names are interchangeable.
How Much Space Should Be Around the Mattress?
Ideally, your mattress should fit securely within its intended frame without substantial gaps or excessive pressure against the sides. A mattress that's too small may move during use, while one that's too large may not sit correctly.
Small manufacturing tolerances can occur, so the goal isn't necessarily an impossibly tight fit. Instead, the mattress should rest evenly on its supporting surface without being forced into the frame.
If you're unsure whether your measurements are compatible, check the manufacturer's recommended mattress dimensions before ordering. Avoid deliberately choosing an undersized mattress to compensate for an awkward frame.
Do You Need to Measure the Bed Slats?
Yes. Mattress support depends on the condition and spacing of the slats, not simply the frame's length and width.
We recommend slat gaps no greater than approximately 7.6cm, or three inches. Our current mattress guarantee also specifies slats wider than two inches, providing guidance on suitable support.
Check that the slats are secure, evenly positioned and free from damage. For larger beds, make sure the central support structure is properly assembled and stable. A poorly supported mattress may develop uneven wear even when its dimensions match the frame perfectly.
Does Mattress Depth Matter?
Mattress depth influences the overall height of your bed, which can affect how comfortably you get in and out. It's especially important when combining a tall bed frame with a deep hybrid mattress.
Our Hybrid® mattress range includes different depths, from the 20cm Hybrid® Essential to the deeper premium models. Adding the mattress depth to the frame height gives you a better indication of the finished sleeping surface.
Depth is also important when choosing fitted sheets and mattress protectors. Our current fitted sheets are designed to accommodate mattresses up to 40cm deep, making them suitable for a variety of constructions.
FAQs
Only when the dimensions are compatible. A European double is typically 140cm by 200cm, compared with a UK double at 135cm by 190cm.
Measuring both can be useful, but the frame's intended sleeping dimensions are particularly important. An older mattress may have changed shape through prolonged use.
Ottoman frames still need appropriately sized mattresses. You should also check the lifting mechanism's weight requirements and the clearance needed to open the storage compartment.
Our bedroom layout guidance suggests approximately 60cm along regularly used sides and around 70cm at the foot when it's part of a walkway.
No. A topper changes cushioning rather than the mattress's length or width, so it won't resolve gaps between an incorrectly sized mattress and frame.
