How to measure curtains – a quick and easy guide to update your windows |

last updated 7 October 2020

Want to learn how to measure curtains quickly and effectively? Curtains are currently taking centre stage in the most dramatic of come-backs as top designers embrace the maximalist aesthetic with stunning results. So if you’re feeling tempted, what should you be considering before taking the plunge? We cover everything you need to know right here...

There are a couple of rules of thumb that will get you off on the right track. Unless you want your window treatments to cover the glass for privacy reasons, or to combat daylight glare in a home office, make sure they can be parked out of the way when drawn to prevent them blocking any natural light. Generally, you will need to allow a minimum of 30cm either side.

With regards to length, always as long as possible to make the window look bigger. ‘There’s nothing worse than curtains that don’t touch the ground, just like trousers that are too short!’ explains Interior Designer Fabrice Bana. Industry expert Sophie Robinson agrees - ‘Don’t scrimp on curtains, they need to be full length and fabulous!’ This also applies to small or short windows, unless you are taking into consideration a bay window, or you are accommodating a piece of furniture that will sit permanently in front of the window. If there is a radiator under the window cill, then a roman blind combined with dress curtains will give you opulent look without the heat loss.

On a handmade curtain with a double, triple, goblet or inverted pleat heading, you will need to calculate your fabric measurement at two and a half times the width of the pole to ensure the curtain folds sit well when shut. For tape headed or wave curtains this can be less, but an absolute minimum of one and a half times the width must be purchased to give the proper fullness. Always allow for between 25 and 40cm extra fabric for turnings, dependent on the chosen heading.

The heading is often dictated by the style of the house. For very traditional interiors, an elaborate triple pleat or goblet will look stunning. Double pinch-pleats are a very versatile designer favourite, giving straight and even folds for a crisp but not too rigid finish. For modern, contemporary glazing, a wave heading is a great option as it falls very simply, has a small park space and has a smart, uniform wave finish when closed. This also works really well under box pelmets for a more tailored look.

As for the fabric, the possibilities are almost endless. Linen, cotton, velvet and wool are all widely used as plain base fabrics or with the addition of patterns applied through being embroidered, woven, screen printed or dip dyed. Combined with a decent lining material, all will hang beautifully. ‘Quality curtain lining will also add extra protection ensuring your curtains last longer, offer insulation and help prevent UV damage from direct sunlight ensuring colours do not fade”, Carl Bennet, Director of Evans Textiles explains.

Ready made curtains are a great option if you are on a budget. For the length, measure from the top of the pole or track to the floor or cill, and for the width measure the width of the window plus 30cm either side to ensure the curtains can be drawn out of the way. It is always possible to get ready made curtains altered to fit your windows by getting them shortened or joining two pairs together like Sophie Robinson - ‘I picked these up from Habitat in the sale and had two pairs stitched together to make them really generous. I also swapped the eyelet heading they came with for a pencil pleat which gives a more fulsome gather.’ In this instance think about investing in a professional seamstress to tailor fit to your windows, and make sure you factor this into the overall cost.

See also:Small Living Room Ideas

How are made-to-measure curtains measured?

The maker or professional installer will use a metal tape measure, a laser measure or a telescopic measuring pole to ensure exact measurements for your particular space.The ‘width’ refers to the length of the track plus any side returns where the track bends back towards the wall. Or the distance between the decorative ends or ‘finials’ on a pole. And the ‘length’ or ‘drop’ is calculated by determining where you want the finished curtain to sit. Extra allowance is needed for the hem (around 6 inches) and for the turn over at the top (around 2 inches). When curtains are being made in pairs, an extra 3 inches is needed for the central overlap.

How much fabric do you need to make curtains?

The majority of fabrics come in 139cm width rolls. The widths are then joined along the seams to the exact pattern forming drops. The number of drops you will need will depend on the size of your window. There are now an increasing number of double width fabrics available at 300cm plus, which can be ‘railroaded’ or turned on their side to create one continuous curtain without visible seams. This works particularly well when used at a large window or bi-fold.

How do you choose the right size curtain?

First look at where the track or pole will be hung. Designers generally recommend as high as possible to make the window and room look taller. Then look at the wall space around the window - is there enough room either side to park the curtains out of the way? If this is not possible, a single side curtain might well be a better bet. Finally, where do you want your curtains to sit - to the cill or to the floor? Or would you like the curtains to ‘puddle’ on the floor, in which case you will need to account for the extra length.

How much does it cost to have curtains made?

‘Bespoke curtains are priced by the size, the heading chosen, the linings and the level of service’, Surrey based curtain maker Clare Young explains. If you also want the face fabric and track or pole sourced, then this will be an additional cost. Look carefully at what the quote includes - do you need to collect and hang them yourself, or will the maker dress them as part of their service? If it’s the latter then any adjustments needed should also be included in the quoted price. Expect to pay from £500 for a fitted pair.

How to measure curtains fitted to a pole

With a curtain pole in place • Width of curtain pole. • c. d. Curtain pole eyelet ring to desired curtain drop. Without a curtain pole in place • Measure the width of the window opening plus the amount you wish the curtains to cover either side of the opening. • Measure the finished curtain length from where you would like your curtains to start and finish.

How to measure curtains fitted to a curtain track

With a curtain track in place • Width of curtain track. • c. d. Curtain track eyelet ring to desired curtain drop.

Without curtain track in place • Measure the width of the window opening plus the amount you wish the curtains to cover either side of the opening. • Measure the finished curtain length from where you like your curtains to start and finish.