Window Treatments

Window treatment dimensions

Curtains are the cheapest way to change the apparent proportions of a room, and the most commonly hung 10 in too low and 20 in too narrow.

Short answer

Hang the rod 4 to 6 in (10 to 15 cm) above the trim at minimum, and usually about halfway between the trim and the ceiling. Extend it 4 to 10 in (10 to 25 cm) past the frame on each side, and buy 2 to 2.5 times the rod width in flat fabric.

The numbers, at a glance

Rod above the window trim
4 to 6 in (10 to 15 cm) minimum
Rod below the ceiling
2 to 4 in (5 to 10 cm) when the gap is small
Rod extension per side
4 to 10 in (10 to 25 cm)
Fabric fullness
2x standard, 2.5x for pleats
Standard panel width
50 in (127 cm)
Ready-made lengths
84, 96, 108, 120 in

Three decisions decide whether curtains look considered or apologetic, and all three are dimensional.

How high. The rod does not belong on the window; it belongs on the wall above it. Four to six inches above the trim is the minimum that stops the hardware looking like it fell. Halfway between the trim and the ceiling is usually right. When the gap above the trim is under 12 in (30 cm), go to the ceiling and stop arguing with it.

How wide. The rod should extend far enough that the panels stack clear of the glass when open. That stack-back is roughly a third of the panel's flat fabric width for a pleated heading, which for a typical pair on a 60 in (152 cm) window works out at 12 to 16 in (30 to 41 cm) per side.

How much fabric. Total flat width should be 2 to 2.5 times the rod width. Two 50 in panels on a 90 in rod is 1.1x, which is not a curtain, it is a flag.

Ceiling Typical rod height Panel length to the floor
8 ft (96 in / 244 cm) 88 to 92 in 90 to 94 in, buy 96 in
9 ft (108 in / 274 cm) 100 to 104 in 102 to 106 in, buy 108 in
10 ft (120 in / 305 cm) 112 to 116 in 114 to 118 in, buy 120 in

In this section#