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  • Writer's pictureSwift Glazing LTD

Tips on Measuring Replacement Windows

Do you plan to measure the replacement windows yourself? This blog post will be quite helpful. Read through it and find actionable tips on measuring replacement windows!

Measuring Replacement Windows Checklist:

What You’ll Need Beforehand

Fortunately, measuring windows is not a process that requires specialized equipment for it to happen. You need to have a few basic things, and you are ready to start measuring your windows for a replacement! Here are the items you will need:

  • A measuring tape for accuracy

  • A notebook for keeping a record

  • A pencil or a pen

How to Measure Replacement Windows?

While measuring your windows, there are two measurements you need to take for most of the cases:

  • Height

  • And Width.

However, remember that if you know that your house walls only allows windows inserted up to 3 inches deep or less, you need to measure the depth as accurately as possible too. You'll be doing all the measurements from the inside, so you don't have to worry about manoeuvring potted plants, trees and other obstacles. You can move the furniture aside, and you're good to go!

Measure the Width of Your Windows:

Remember that the width measurements happen without the parting beads or trim pieces unless you have the window removed.

Start measuring the width of your window. And take multiple readings –a minimum of 3 if your windows are of average height. You can take these three readings from different window sections, for example, one from the top, one from the centre and one from the bottom.

However, if your windows are sizeable, you should divide your windows into more than 3-sections and get their measurements. Make sure that all of them are within 1/8 inches.

Don't forget to note them down, or you'll just keep forgetting and having to re-take them again and again.

Separate the smallest measurement. That is what you will need for ordering a replacement window to ensure a perfect fit.

Measure the Height of Your Windows:

Like the width measurement, you also need to take multiple readings/measurements when measuring the height (minimum 3). For windows that are usually huge, for example, bay windows, try to take more than 3 measurements from different sections and ensure they have even spacing between them.

Again, ignore the beads and trips and start measuring from one jamb to another.

Note down your measurements as you take them and circle the smallest one.

Is Your Window Opening Square?

Here’s how you can check:

The window installer will need to know whether your window openings are square. It helps the installer understand if the window opening requires adjustments or shims before the installation of a new window.

A square opening has four 90 degrees corners and equal diagonals.

To find out if your window has these characteristics, start by measuring diagonals. Place your measuring tape on one corner of your window, say the top left corner, and move towards the one below and opposite (bottom-right). Now do the same by starting from the top right corner. Note down these measurements. If the two matches exactly, your windows are a perfect square.

A slight difference (up to 1/4th of an inch) is also acceptable. However, if the range is wide, your window installer will have to make adjustments.

He will either use wooden shims or he will adjust the openings for a better fit. You can also order customized windows for those openings.

Do You Have an Arch Top or Architectural Windows?

Archtop or architectural windows have straight edges as well as curvature. However, they are measurable most of the times.

For measuring architectural windows you want to replace, you need to measure the straight-lined sections first. Once done with them, measure the curvature by placing your measuring tape from the lowest to the highest point. Again, ignore the trims and measure from the jambs. Note down all the readings.

Different kinds of architectural windows are present, but they always have a curvature you can measure to its centre. These measurements will help you with ordering a perfect replacement and your window installer in making the right adjustments.

If you found this post on how to measure replacement windows helpful, you will love the rest of our blog. Don’t forget to take a look at it!


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