Reference
Glossary
Plain definitions of the words on a measuring guide, a spec sheet or a workroom order, with the chapter that explains each one in full.
Some of these words are measurements and mean the same thing in every guide. Others are makers' words ("blackout", "room darkening", "light filtering"), which mean what that maker means; those definitions say so. Where two makers use a word differently, the chapter linked beside it explains how.
| Term | What it means | Where it is explained |
|---|---|---|
| Apron | The strip of trim below the window sill. As a curtain length, "apron length" ends at the bottom of it. | Style and proportion |
| Blackout | A maker's word for a fabric or lining meant to stop light passing through it. No maker gives a percentage for blackout shades; one lining maker defines blackout lining as blocking 99 percent or more of daylight. Light can still come round the edges. | Daylight, glare and darkness |
| Bracket | The piece screwed to the wall, the trim or the ceiling that holds a rod, track, blind or shade. | Hardware and installing |
| Break | A curtain length a little longer than the floor, so the hem bends where it meets it. One maker gives 1/4 to 3/4 in. | Style and proportion |
| Café curtain | A short, straight-hanging curtain over the lower part of a window, sometimes with a second tier above. | Privacy by day and by night |
| Casing | The trim around a window opening. An inside mount sits within it; an outside mount covers it. | Measuring for blinds and shades |
| Cellular shade | A shade of fabric formed into rows of cells (a honeycomb) that traps air. Made as single cell or cell-within-a-cell. | Curtains, shades, blinds and shutters |
| Center overlap | Where a pair of curtains meets, the amount each one laps past the middle so no gap shows when they are closed. | Measuring for curtains |
| Continuous loop | An operating cord or bead chain formed into a closed loop. A loop is a strangulation hazard for young children unless it is held taut or out of reach. | Cords, children and fire |
| Cordless | Operated with no cord a child can reach: lifted by hand, by a spring, with a wand, or by a motor. The industry standard counts a motorized product as cordless. | Cords, children and fire |
| Cornice | A rigid top treatment, like a box across the top of the window, that hides the top of the curtains or shade and their hardware. | Style and proportion |
| Custom | Made to order from your measurements. In the industry safety standard, any product that is not stock. Custom products follow different cord rules. | Buying, ordering or making; Cords, children and fire |
| Depth | The front-to-back space inside the window frame, from the glass (or whatever sticks out from it) to the front edge of the casing. It decides whether an inside mount fits; each maker publishes a minimum. | Measuring for blinds and shades |
| Finished length | The length of a curtain as made and hung, from its top to its hem. Fabric is cut longer to allow for the header and hems. | Measuring for curtains |
| Flush mount | An inside mount deep enough that the blind or shade sits wholly inside the frame, its front level with the casing. Makers list the depth for it separately from the minimum. | Measuring for blinds and shades |
| Fullness | How much wider the curtain fabric is than the space it covers, written here as a multiple: 2 times fullness is double. Some makers write it as a percentage, and their percentages do not all mean the same thing. | Measuring for curtains |
| Glare | Light bright enough, directly or reflected, to make it hard to see a screen, a page or a face. Usually traced to one window at one time of day. | Daylight, glare and darkness |
| Grommet | A curtain heading with metal or plastic rings set into the fabric, which slide straight onto a pole. Best for panels that are not opened and closed often, in one maker's guide. | Style and proportion |
| Header | The fabric folded at the top of a curtain, above the heading, that gives the top its body. Its allowance is part of the cut length. | Buying, ordering or making |
| Heading | The way the top of a curtain is made and attached to its rod or track: pinch pleat, grommet, rod pocket, ripplefold and so on. | Style and proportion |
| Inner cord | A cord that runs through the slats or fabric of a blind or shade to raise it. On older blinds a child can pull an inner cord into a loop. | Cords, children and fire |
| Inside mount | Fitted within the window opening, inside the casing. | Measuring for blinds and shades |
| Interlining | A layer between the face fabric and the lining that adds light blocking, insulation, privacy and body. Bump is a heavy cotton interlining. | Fabric, linings and fading |
| Lambrequin | A stiff, flat valance with a shaped lower edge, often coming down at each side of the window. Also called a pelmet. | Style and proportion |
| Light filtering | A maker's word for a fabric that lets diffused daylight through while hiding a direct view by day. | Daylight, glare and darkness |
| Light gap | The strip of light at the edges of an inside-mounted shade or blind, left so it can move. One maker's cellular shades leave 3/16 in each side by design. | Measuring for blinds and shades |
| Lining | A fabric layer sewn or hung behind the face fabric. It protects the face from sun, adds body and blocks some light; blackout and reflective linings do more. | Fabric, linings and fading |
| Openness factor | The percentage of direct light that passes straight through the gaps in a screen fabric's weave, typically 1 to about 13 percent. | Daylight, glare and darkness; Labels and spec sheets |
| Outside mount | Fitted on the wall or trim, outside the opening, overlapping it on each side. | Measuring for blinds and shades |
| Pinch pleat | A heading in which the fabric is gathered into groups of folds pinched together near the top. Made to be opened and closed daily. | Style and proportion |
| Projection | How far a bracket holds a rod or track out from the wall. Each layer of curtains needs more of it. | Style and proportion; Hardware and installing |
| Puddle | A curtain made long enough to lie in folds on the floor. Makers give from 1 in to 10 in of extra length. | Style and proportion |
| Return | The end of a curtain or valance that turns from the front of the rod back to the wall, closing the side gap. | Measuring for curtains |
| Ripplefold | A heading for a track in which the fabric hangs in even, continuous S-shaped waves, set by the spacing of the carriers. | Style and proportion |
| Rod pocket | A sewn channel along the top of a curtain that the rod slides through. Suits panels that stay put. | Style and proportion |
| Roman shade | A fabric shade that raises in horizontal folds. Styles include flat, cascade, relaxed and hobbled; names vary by maker. | Curtains, shades, blinds and shutters |
| Room darkening | A maker's word for an opaque fabric meant to darken a room. No maker gives a percentage that separates it from blackout. | Daylight, glare and darkness |
| Sheer | A thin, see-through curtain fabric. It gives privacy and light by day, while outside is brighter; after dark, with lamps on, it shows the room. | Privacy by day and by night |
| Shutter | Hinged panels on a frame, fitted in or over the window, that swing open. | Curtains, shades, blinds and shutters |
| Solar shade | A roller shade in an open-weave screen fabric, chosen by its openness factor and color to cut glare and heat while keeping some view. | Daylight, glare and darkness |
| Stack height | The space a blind or shade takes at the top of the window when it is fully raised. | Measuring for blinds and shades |
| Stackback | The wall space open curtains take up beside the window. | Measuring for curtains |
| Stock | Made in fixed sizes before anyone orders it; still stock if it is cut to size in the store or sold online. Stock products follow the federal cord rule. | Buying, ordering or making; Cords, children and fire |
| Tension rod | A spring-loaded rod held between the two sides of a window frame by pressure, with no screws. | Hardware and installing |
| Toggle bolt | A hollow-wall anchor whose bar or wings open behind the wallboard. It needs clear space behind the wall to open. | Hardware and installing |
| Top-down bottom-up | A shade that opens from the top, from the bottom or both, so the lower window can stay covered while sky light comes in above. | Privacy by day and by night |
| Traverse rod | A curtain rod with sliding carriers that draw the curtains open and closed along it. | Measuring for curtains |
| Ultimate load | The load at which an anchor failed in a lab test. Some makers publish this figure and say to design to a quarter of it. | Hardware and installing; Labels and spec sheets |
| Valance | A horizontal fabric hanging across the top of a window, generally to hide curtain tops and hardware. | Style and proportion |
| Visible transmittance | The percentage of visible light that gets through a fabric or film, through the gaps and the material. Lower means less glare. Written Tv on fabric sheets and VLT on film. | Daylight, glare and darkness; Labels and spec sheets |
| Wand | A rigid rod hanging from the headrail, used in place of a cord to tilt slats or to draw a curtain or shade. | Cords, children and fire |
| Working load | The load a maker says to design to. Where a maker publishes an ultimate load, the working load is usually a quarter of it. | Hardware and installing; Labels and spec sheets |
For the numbers printed on labels and spec sheets (openness, the AERC rating, ultraviolet percentages, anchor ratings), see Labels and spec sheets.