Curtain length and fullness: how much fabric a window needs

Curtains look best when their length suits the proportions of the room and the fabric is one and a half to two times the width of the track. The fullness sets both the look and the amount of fabric: a wave heading takes 2× the length of the track, a tape or eyelet heading 1.5× and a pinch pleat heading 2.5×. A hem weighted to suit the fabric, and finished well, makes the curtain fall properly and keep its shape for years.

Three classic lengths at floor level

Level with the floor, with a 1–2 cm gap, is the most practical and versatile length for everyday use. The fabric stays off the floor, keeps cleaner and suits homes with children or pets. Even in new homes the floor can vary by 5–10 mm across the width of a window, so measure at several points.

Just touching the floor is a modern classic that makes the room look larger. It needs a dead-level floor: on an uneven one, the fabric lies on the floor at one side and hangs short at the other. Under the standard Lithuanian ceiling height of 2.5–2.7 m, floor-length curtains make the room look taller.

Pooled curtains are more formal: the fabric lies 10–20 cm on the floor in a soft fold. They suit showpiece rooms. An uneven floor no longer matters, but the fabric gathers dust and needs cleaning more often.

Shorter curtains end 1 cm above the sill or 10–15 cm below it: in a kitchen, over a radiator or furniture under the window, or where the curtain is paired with a roman blind. The diagram shows all four lengths and the fabric width for each heading.

Fullness: 1.5×, 2× or 2.5×?

Fullness is how many times wider than the track the fabric must be for the folds to form properly. It is one of the commonest mistakes: clients save on fabric, and even an expensive one then looks thin.

A wave heading needs a ceiling track with gliders and cannot hang on a standard pole. An eyelet heading needs an open pole no more than 35 mm in diameter. A worked example: a 300 cm track × 2 (wave heading) = 600 cm of fabric in all. When the curtain is taller than the roll width of the fabric, the fabric is turned and joined in widths, so more of it is needed.

The hem: weighted or plain?

Lead weight tape in the hem suits light, soft fabrics best: voile, chiffon and soft voile. It weighs the hem down so the fabric falls well. The tape must match the weight of the fabric exactly: one that is too heavy makes an unsightly roll along the bottom.

A plain hem is turned up and stitched, giving the fabric a clean, straight bottom edge. It suits coarser-weave net sheers and structured fabrics, stops threads pulling out and makes the fabric last longer.

Common mistakes when choosing length and fullness

• —Too little fabric across the width: even an expensive fabric looks flat. A wave heading needs 2× the track length, a pinch pleat heading 2.5× and a tape heading at least 1.5×.
• —Measuring the drop from the sill instead of the track: the curtains come out too short and make the ceiling look lower. Always measure from the underside of the track to the floor.
• —A wave heading on a standard pole: the waves do not form and the gliders do not fit. Use only a ceiling track with gliders.
• —Not checking that the floor is level: even in new homes the difference can reach 5–10 mm. Measure at several points.
• —Lead weight tape too heavy for a light fabric: an unsightly roll forms along the bottom.

Frequently asked questions

How much fullness do curtains need?

It depends on the heading: 2× the track length for a wave heading, 2.5× for a pinch pleat heading and 1.5× for a tape or eyelet heading. A wave heading never needs more than 2×, because the gliders on the track set the spacing of the waves and keep them even. The higher the fullness, the more fabric it takes and the fuller the folds.

What length do you recommend for a bedroom, a living room and a child's room?

Floor length for most rooms, because it makes the window look finished: 1–2 cm above the floor in a child's room, and just touching or resting slightly on the floor in a living room or bedroom. For fullness, allow 1.5× the track length for an eyelet or tape heading, 2× for a wave heading and 2.5× for a pinch pleat heading.

How do I choose the track for each heading?

A wave heading needs a ceiling track with gliders and will not work on a standard pole. An eyelet heading needs an open pole no more than 35 mm in diameter. For blackout, use a ceiling track with wall returns: only that closes the gap between the track and the wall.

How does the width differ between sheer and lined curtains?

Sheers are usually made with a wave heading, so they take 2× the track length. Lined curtains suit a tape heading (1.5×) or a wave heading (2×). Either way, the track should run 20–30 cm past the window on each side, so the curtain covers the window without gaps.

What do sheer curtains cost?

Sheer fabrics cost €9.50–16.50 per metre, from Voile at €9.50 to Nobel at €16.50. For a window 2 m wide with a 2.5 m track and a wave heading: Voile 5.3 m × €9.50 = €50.35, making 5.3 m × €8 = €42.40, ceiling track 2.5 m × €9 = €22.50. About €115 in all, before fitting.

What do lined curtains cost?

Lined curtain fabrics cost €24–43 per metre, depending on how dark they make the room (dim-out or blackout); blackout lining costs €11 per metre. Lined curtains often take more fabric, so they can cost more than sheers. The final price depends on the fabric, the track and the fitting.

How do I measure the drop when the floor is uneven?

Measure from the track to the floor in three places across the width of the window, and go by the lowest point of the floor: even in new homes the floor can vary by 5–10 mm. For a curtain that ends above the floor, take 1–2 cm off the smallest figure; for one that lies on the floor, add 10–20 cm.

What do tracks and mechanisms cost?

A ceiling track costs €9 per metre in white or €10 per metre in black, a wall-fixed pole from €14 per metre, and a motorised track from €170 per metre, fitted and programmed. Making costs €8 per metre for sheer curtains and €13 per metre for lined ones (drop up to 300 cm), and fitting a ceiling track from €9 per metre.

Sheer curtains: lead weight or plain hem?

It depends on the fabric, so judge its thickness and weight first. Lead weight tape must match the weight of the fabric exactly: too heavy for a light fabric, it makes a roll along the bottom and spoils the look. A plain hem suits heavier fabrics that hold their shape on their own.

How long should curtains be from the floor?

The classic length ends 1–2 cm above the floor; for a more formal look, the fabric lies 10–20 cm on the floor. In standard Lithuanian flats, with ceilings of 2.5–2.7 m, floor-length curtains suit almost any room.

When should curtains pool on the floor, and when should they end level with it?

Pool them in showpiece rooms, living rooms or bedrooms where a more formal look is wanted. End them just above the floor in children's rooms and rooms where the curtains are handled often; this is also the length to choose on an uneven floor.

Do floor-length curtains make a room look taller?

Yes, especially in Lithuanian flats of standard height (2.5–2.7 m). Fixing the track 10–15 cm above the top of the window adds to the effect: the wall reads as taller, with no building work at all.