The Quick and Easy Way to Measure for Window Blinds

Measuring for window blinds isn’t difficult – here’s what you need to know to get the right fit.

Open Concept Living Room and Dining Room

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Trendy coral-colored X-benches serve as an informal room divider in this open-concept living room and dining room. The rooms are united through shared natural elements, like the wood tables, and the complementary designs of the scroll-back chairs and Chesterfield sofa.

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Brian Kellogg, scripps Networks, LLC

You’ve spent hours picking them for your home and you want them to fit perfectly. Now, how do you measure for window blinds, again?

Inside Mount or Outside Mount

There are two ways to mount blinds, inside the window frame and outside it. For a clean, built-in look, use inside mount. This also allows you to hang other window coverings, like draperies, over the blind.

Use outside mount when you want to make a window look wider and longer, or when you have an unattractive window that you want to hide. It’s also a good option if you have a window that is noticeably off square.

When measuring, use a steel measuring tape and measure to the nearest 1/8-inch. Don’t round your measurements.

Note which measurement is the width by marking a “W” next to it, and note the height with an “H.” Always put the width measurement first. Remember: W x H.

Unless told otherwise, don’t deduct for the mounting brackets or head rail; the factory will do this. Provide the exact window size.

Tip: When using an inside mount, first measure to make sure the frame is deep enough to accommodate the hanging hardware.

Inside Mount Blinds

Once you’ve determined your frame is deep enough for the hardware, take three measurements, one at the top of the window one in the middle and one at the bottom. Use the narrowest width as your measurement.

For the height, measure left, right and center, and record the tallest height.

Outside Mount Blinds

When measuring for outside mount horizontal blinds, start by measuring the window’s width. Then, if possible, add at least 3 inches to each side to ensure you’re covering the light gap and to maximize privacy.

Then measure the window’s height and add at least 2.5 inches to allow the space for mounting brackets and overlap at the bottom of the blind.

Shortening Faux Wood Blinds

There are a variety of reasons to shorten faux wood blinds: you’re hanging old blinds on a new window, you want to correct an accidental mis-measurement, or the off-the-rack blinds you bought are simply too long.

Here’s what you’ll need:

·   scissors

·   flat-head screwdriver

·   needle nose pliers or tweezers

Start by lowering the blind fully. Choose the new bottom slat of the blind by selecting the slat that’s even with, or slightly below, the windowsill.

There should be three cords: a smooth lift cord (that lifts the blinds), a braided ladder cord (that holds the blinds vertically) and a connector cord between each slat, which secures the blinds horizontally.

Count two slats down from the bottom of the sill and cut the ladder cords on both sides of the blind. Warning: Don’t cut the lift cord or the connecting cord!

The slats will fall to the bottom, supported by the ladder cords. Then, about six inches below the windowsill, trim the lift cords and pull out the last two slats, the ones below the new bottom slat.

Tip: Save a couple of the slats for future use.

Use the screwdriver to pry the plugs from the underside of the bottom rail. Slide the rail free from the old slats and cords. Use tweezers or pliers to pull the cut lift cords out of the plughole. Slide the rail onto the connecting cords, just below the bottom slat.

Pull all four of the lift cords out of the last loops on the ladder cord. Then reinsert the lift cords in the holes on the front and backsides of the bottom rail. Pull the lift cords through the bottom holes and double-knot each pair of cords together. Trim the lift cords.

Trim the ladder cords and stuff them, along with the lift cords, into the plughole. Then tap the plugs back in place with the hammer.

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