how to measure for replacement windows
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How to Measure for Replacement Windows

From Tape to Trim

Windows are subject to extreme abuse by weather and will wear out over time. Replacing old and weathered windows in your home is a task that anyone can try. When you decide to replace your windows, it is the perfect opportunity to make your home more energy-efficient, safeguard it against the elements and increase its resale value. In this article, we will go over how to measure for replacement windows.

Before you start the measuring process, it is important to note the condition of the existing window frame. Replacements will be attached to the current frames, and therefore, they cannot be damaged or rotten.

Necessary Tools

Window measuring does not require any fancy tools. You will only need the following:

  • A measuring tape.
  • A notepad.
  • A pen.
  • A stepladder or longer ladder; depending on window placement.

Window Measurement Tips

The most important part of measuring windows is to establish an accurate measurement of the width and height. Windows need to be measured from the inside for accuracy.

Measure the Width

At least three accurate measurements at different horizontal points are needed — one at the top, one in the middle and one at the bottom of the window.

Start measurements from the outside posts and not from the trimmings, as those will be removed with the existing window. If the window is taller than standard, take extra measurements to ensure you cover the entire width.

Sketch the window shape on a piece of paper and indicate its measurements, circling the smallest width measurement. This is the rough width measurement.

Height Measurement

Measure three vertical heights — one on either side and one in the center of the window. Take more measurements between these three sections if the window is exceptionally large or built out like a bay. Don’t measure the trims or outside posts, as these will be removed.

Write down the heights and circle the lowest measurements – this is the rough height measurement.

Depth Measurement

This is vital, as some windows are too deep to refit into the opening. Measure from the inside to the outside of the frame, as well as from edge to edge.

Circle the lowest measurement — this is your rough depth measurement.

Round the Numbers

Take the circled measurements of width, height and depth and round them down to the closest one-eighth of an inch.

Buying Custom Replacement Windows

Home improvement centers usually store custom windows, although they are not always the perfect size. It is better to order them according to your measurements, as that will provide the ultimate fit.

Measuring Different Types of Windows

No matter the size or shape of the outdated or broken window, there will always be a perfect replacement. This is also the perfect time to invest in energy-efficient windows or modern units that brighten or modernize your home.

Square Windows

Each corner should be 90 degrees. The length should be equal to the height. If not, notify the installers upfront so they can make the necessary adjustments to the opening when replacing the window. Measure the corners diagonally across the window from the top left to the bottom right and the other way around. Optimally, the difference between the two should be no more than one-quarter inch.

Arched Top Windows

It is a bit more challenging to measure a curved window, but you can make it easier by calculating the square part first. Measure the distance from the lowest part of the window to the highest point of the arch.

Extra Tips for Measuring Windows

You can save a lot of money on contractors if you know how to measure for replacement windows and install them yourself by following these tips:

  • All measurements are taken from inside the home.
  • Accuracy is vital, as this will ensure proper replacement and maximize energy savings.
  • Always list the width before the height.
  • If you want to install an awning or swinging window, consider your outside space, as it may not fit if they are over a roof or next to a garage.
  • New windows should fit squarely and tightly into the frames.

Getting the measurements wrong will result in an ill-fitting window or a piece that you cannot utilize at all. If you do not feel confident enough to measure yourself, consulting a professional window replacement company is your next step.

Contractors are experienced in measuring all sizes and types of window units. Most professional window replacement companies even offer warranties on their windows, saving you time and money.

One thing is for sure, installing more windows in your home allows for beautiful outside views and loads of natural lighting.