How to Measure Cushions for Outdoor Furniture?

To measure cushions for outdoor furniture, measure the seat frame itself rather than the old cushion, taking width at the front edge, depth from the back support to the front edge, and thickness at the deepest point. Work in centimetres, measure to the outside of the frame where the cushion is meant to sit flush, and take three readings across awkward shapes to catch any taper. If the frame is slightly wider at the front than the back, the front measurement is the one that governs the fit.

Getting this right matters more outdoors than indoors. A cushion that is even two centimetres too wide will bow upwards in the middle, collect rainwater and wear along the fold. One that is too small slides forward every time somebody sits down. Neither problem shows up in a showroom, but both appear within a fortnight of real garden use.

What to Measure and in What Order

Start with width. Place the tape along the front of the seat, from the inside face of one arm to the inside face of the other. If the seat has no arms, such as a bench or a lounger, measure the full frame width and subtract nothing. Next, measure depth from the point where the back support meets the seat, straight out to the front edge. Sit a rigid ruler against the back so the tape does not follow the curve of the frame, since a curved reading will always give you a cushion that is too deep.

Thickness comes last and is the measurement people guess most often. Compress nothing when you measure it. Take the height of the cushion at rest, not under load. A thickness of 5cm to 8cm suits dining seats, while lounge seating usually sits between 8cm and 12cm. Deeper than that on a low frame and you lose back support because your knees end up above your hips.

Measuring Different Frame Types

Rattan and weave frames often have a slight inward taper at the back. Measure width at the front and at the back, then order to the narrower dimension so the cushion drops in cleanly. For slatted timber seats, check whether the slats are level or dished. A dished seat needs a slightly firmer or thicker cushion so it does not sink into the hollow.

Corner and modular seating is where most mistakes happen. Measure every module separately and label your notes, because units that look identical often differ by a centimetre or two. The corner piece is usually a square or a wedge, so record both edges of the wedge rather than assuming symmetry. If you are replacing cushions for a set from our modern outdoor garden seating sets UK range, keep the original layout diagram if you still have it and mark each module by position.

Loungers need a length measurement taken along the reclining surface with the back fully lowered, plus a note of where the hinge falls. A cushion that ignores the hinge point will crease across the wrong line and split its cover early. For frames such as our modern outdoor garden sun loungers UK, measure both sections of the frame either side of the hinge and add them together.

Back Cushions and Scatter Cushions

Back cushions are measured from the seat surface up to the top of the back frame, then across the back at its widest point. Deduct one centimetre from the height so the cushion does not ride up above the frame line. If the back rails are open weave, remember that a thin back cushion will push through the gaps, so 8cm minimum is sensible.

Scatter cushions do not need to match the frame at all, which makes them the easiest way to change how a set looks without replacing anything structural. Standard sizes of 40cm and 45cm square suit most garden seating. Choose covers that unzip and wash, because these are the cushions that take suncream, drinks and garden dust.

Allowances, Seams and Fill

Do not add a tolerance for comfort. Outdoor covers are cut with their own seam allowance, so if you add your own the cushion arrives oversized. Order to the exact frame measurement and let the maker handle ease.

Fill affects fit as much as dimensions do. Reticulated foam drains and dries quickly, which suits seats left out through a British summer. Polyester wadding feels softer but holds water for longer and needs a well drained cover. Fibre wrapped foam sits in between and holds its shape reasonably well on dining chairs. Whichever you choose, look for a cover with drainage holes or a mesh base panel, because water gets in eventually no matter how good the fabric.

Fabric and Fixings

Solution dyed acrylic holds colour best in direct sun. Polyester with a water repellent finish is a reasonable middle option for seats that live under a parasol or a canopy. Whatever the fabric, check the fixing method before ordering: ties, hook and loop strips, or elasticated straps all need a frame detail to attach to. Cushions on a raised dining seat almost always benefit from ties, since they otherwise slide off every time a chair is pulled out.

If you are choosing cushions for a set you have not bought yet, it is easier to shop the frames and cushions together. Our modern outdoor garden dining sets UK sale listings state seat dimensions, which lets you compare cushion sizes before anything arrives. The same applies when you are adding seating gradually to a patio using pieces from our outdoor occasional garden seating UK selection, where seat depths vary noticeably between styles.

Storage Between Uses

Measuring well is only half the job. Cushions last far longer when they are brought in or stored dry. Measure your storage space at the same time as the cushions, because a set of six dining cushions takes up more room than most people expect. A garden storage box, a shelf in a shed or a slim ottoman indoors all work. If you plan to store them outside, allow ventilation so trapped damp does not turn into mildew.

At Furniture in Fashion we find customers who write their measurements down once, keep them on their phone and reuse them each season rarely order the wrong size twice. It takes ten minutes and saves a return.

Fabric and Filling Change the Fit

Two cushions with identical stated dimensions can sit very differently depending on what is inside them. Foam holds its shape and fills a seat frame tightly, so it needs accurate measurements with very little tolerance. Fibre filling compresses more readily and forgives a centimetre either way, which makes it the safer choice if your frame is slightly irregular or has softened with age.

Fabric matters just as much. A tightly woven outdoor fabric holds a crisp edge and looks tailored when the measurements are right, but obviously baggy when they are not. A softer fabric drapes over a frame and disguises small discrepancies. If you are ordering for an older set with worn or uneven timber, the softer option is usually the more forgiving one.

Allow for Removable Covers

If the cushions have zipped removable covers, check whether the stated size refers to the cover or the insert inside it. A cover made to exactly the same dimensions as its insert will be tight to fit and tight to close, and it will look pleasingly full once in place. A cover made slightly larger is easier to remove but can look loose after the insert settles.

Washable covers are worth the small extra cost on garden seating, since outdoor fabric collects pollen, dust and the occasional spill across a season. Measure with the cover fitted rather than removed, because seam allowance and piping add a few millimetres that affect how neighbouring cushions sit against one another on a bench or a corner unit.

Frequently Asked Questions

Should I measure the old cushion or the frame?

Always the frame. Used cushions spread, compress and sometimes were the wrong size to begin with, so copying them repeats the error.

How thick should garden dining cushions be?

Between 5cm and 8cm is comfortable for dining without raising you too high above the table. Thicker pads suit lounge seating where you sit lower and for longer.

Do outdoor cushions need to be exactly the same size as the seat?

They should match the frame dimensions closely. A cushion that fills the seat without bowing is correct. Slightly under is better than slightly over, since an oversized cushion buckles and wears along the crease.

Can I use indoor cushions outside in summer?

Only briefly and only in dry weather. Indoor fill holds moisture, and indoor fabric fades quickly in direct sun, so the saving is short lived.

How do I measure a curved or wedge shaped corner seat?

Record the two straight edges of the wedge, the widest point across the curve, and the depth at the centre. Provide all four figures rather than averaging them.