To measure for blinds, first decide on an inside mount (inside the window frame) or an outside mount (on the wall or trim above it). For an inside mount, measure the width at the top, middle, and bottom and use the narrowest, then measure the height at left, center, and right and use the longest. For an outside mount, measure the area you want to cover and add a few inches on each side. Always measure to the nearest one-eighth inch, and never reuse one window’s numbers for another.

Inside mount or outside mount, which do you need?

The mount decides how you measure. An inside mount sits inside the window frame for a clean, built-in look that shows off the trim, and it needs enough depth in the frame for the blind to fit. An outside mount attaches to the wall or trim above and outside the opening, which makes a window look larger, hides an out-of-square frame, and blocks more light. Shallow frames, cranks, or obstructions often push you to an outside mount. Choose the mount first, because the measuring steps differ.

How do you measure for an inside-mount blind?

For an inside mount, precision is everything, because the blind is cut to fit snugly inside the opening:

• Measure the width at the top, middle, and bottom of the opening. Use the narrowest of the three.
• Measure the height at the left, center, and right. Use the longest of the three.
• Do not round or adjust the numbers. The workroom makes the deductions needed for a proper fit.
• Check the frame depth to be sure it is deep enough for the product you want.

How do you measure for an outside-mount blind?

For an outside mount, you are covering an area rather than fitting an opening. Measure the width of the space you want the blind to cover, then add about 2 to 3 inches on each side to block light and give privacy. For height, measure from where you will mount the headrail, usually a few inches above the opening, down to where you want the blind to end, whether at the sill, below it, or to the floor. More overlap means less light leak around the edges.

What are the most common measuring mistakes?

Custom blinds are cut to your numbers and cannot be returned, so small errors get expensive. The frequent ones are: measuring only one point instead of three across the width and height, rounding to the nearest inch instead of the nearest eighth, mixing up width and height (always list width first), reusing one window’s measurements for a similar-looking window, and forgetting to check frame depth for an inside mount. Bay windows, arches, and sliders add angles and stacking that are especially easy to get wrong.

Should you measure yourself or have a pro do it?

For a couple of standard windows, careful DIY measuring can work. For a custom order, and especially for a whole home or any specialty windows, a professional measure is worth it. On a custom blind, a fraction of an inch off means gaps, binding, or a unit that will not fit, and since it is cut to size it cannot be returned. That is why Long Island Custom Blinds includes professional measurement as part of the free in-home consultation, so the fit is guaranteed and the mistake risk is on us, not you.

FAQ

Do you measure width or height first for blinds?

Always width first, then height. The industry lists measurements as width by height, and reversing them is one of the most common ordering errors.

How much space do you need for an inside-mount blind?

Enough frame depth for the headrail to sit inside the opening, which varies by product. Deeper products like some cellular or wood blinds need more depth. If the frame is too shallow, an outside mount is the fix.

How accurate do window measurements need to be?

To the nearest one-eighth of an inch. Custom blinds are fabricated to your exact numbers, so rounding even to the nearest quarter or half inch can cause gaps or a poor fit.

Can you return custom blinds if they do not fit?

Usually not, because they are made to your specific window measurements. That is the biggest reason a professional measure is worth it on a custom order, since a mismeasured blind cannot be returned.

Rather not risk the measurement? Long Island Custom Blinds measures every window for you during a free in-home consultation across Nassau, Suffolk, and Queens. Call (516) 363-4670, visit longislandcustomblinds.com, or stop by our showroom at 2000 Fisher Avenue, Suite 122, Merrick, NY 11566.

Related services: Custom Blinds | Shop-at-Home Consultation | Professional Installation

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