how to measure for replacement windows

Jan 07, 2025

How to Measure for Replacement Windows

Replacement windows and doors are a great way of improving the look of your home and cutting your energy bills into the bargain. New windows combine style with practicality, helping transform the look of your house while providing one of the most effective ways of increasing its energy efficiency. 

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Window Replacement Means Knowing Your Window Size

If you’re thinking about replacing your windows, an important first step is measuring them to ensure the new windows you fit are the correct size. This means knowing the width and the height of the windows. So you will need to do height and width measurement. 

But it can get confusing. Do you measure the window’s full frame? And does it also include the window sash, jamb, or the window sill?

Wondering where to start? We’ve got you covered on measuring for replacement window installation with this DIY guide. If you’re ready to get started on window replacement, contact Remodel USA today!

Read on to find out how to measure for replacement windows to get correctly sized windows for your home. If you want to get replacement windows installed without the hassle of measuring for them yourself, simply contact Remodel USA today!

Four Steps for Measuring Windows

So you’ve made a big home improvement decision–to replace your existing windows. You’re hoping for all the aesthetic and energy efficiency benefits that come with this home improvement plan. You’ll probably be wondering how to measure windows for replacement to ensure the new windows you fit are the right size. 

That’s where making accurate measurements of your existing windows is vital. To start, you’ll need a good quality tape measure, a ladder, and a pen or pencil and notebook. Remember that window measurements are recorded in inches. They should always follow this format–width x height. 

The basic process for measuring windows can be broken down into the following steps:

Ensure the Window Frame Corners Are at 90-Degree Angles 

You need to know your window corners are in what’s called “square alignment” before you order any replacement. Each of the four corners should be at a right angle, also called a 90-degree angle. If they are not, that means they are not standard window sizes. You can discover this by measuring the windows from the upper left to the bottom right corner, and then from the upper right corner to the bottom left. If the numbers are within ⅛ of an inch of each other, they have four square corners.

Measure the Window Width

Next, it’s time to assess how wide the window is. The window’s width should be measured at the top of the window, center, and bottom of the window. Measure from brick to brick, not from frame to frame. Your measurements should reflect the total aperture (window opening or “rough opening”) where the window is fitted. Otherwise you could just wind up measuring a badly fitting existing frame. 

Take Window Height Measurements 

Then it’s time to figure out the height, so take a measurement of the window height at the far left side and far right side of the window, and at the center. 

Measure the Window Depth

The final step is to measure the window’s depth. Measure from the window trim inwards. You can round up all your measurements to the nearest quarter inch. It’s a great idea to check your measurements at least two or three times. It’s much less problematic to get them right than to have to alter window frames that have been manufactured. As the expression goes, measure twice, cut once.  

Window Numbering 

New windows come in a huge range of sizes and types, although there are standards manufacturers work to. Different types of windows will typically have a maximum width and length with incremental variations in size. 

When it comes to ordering replacements, window sizes are numbered by manufacturers using a four-digit code to represent width and height. For example, a window that measures 48 inches by 36 inches (four feet by three feet) is denoted 4030. A window that measures 24 inches by 44 inches (two feet by three feet eight inches) is noted as 2038, and so on. 

What to Do If You Can’t Measure Your Windows?

There are several reasons that you may not be able to measure your home’s windows:

  • You don’t have a tape measure.
  • You don’t have a ladder, or the ability to reach higher places in your home.
  • You are not mechanically inclined. 
  • You are not interested in DIY.
  • You just don’t want to hassle with doing these measurements yourself.

If any of these things apply to you, don’t worry. Simply reach out to our window replacement experts at Remodel USA today. We’ll do the measurements for you! Then we’ll take care of everything else when it comes to window replacement. 

Advantages of Replacement Windows

Once you’ve measured your windows and ordered replacements–or have had Remodel USA install them in your home–you can look forward to the benefits of new windows for your home. They include improved security, increasing the property’s value, and better energy consumption. 

For example, windows that are damaged or weakened are a target for burglars. New windows, locks, and fittings can increase security, giving you peace of mind. 

New windows can also provide a boost to the value of your property. Although old window, old frame and wood window styles are sometimes preferred for aesthetic reasons, there is a wide range of practical replacement windows available to suit all tastes.

Perhaps most importantly, new windows are a great way of reducing energy consumption. Worn-out window frames and single-glazed windows tend to mean more energy is used for heating. So replacing windows can help cut your energy bills and make your home more environmentally friendly, too. 

Why Choose Remodel USA? 

Remodel USA has been providing homeowners in Maryland, Washington DC, Virginia, and Pennsylvania with new replacement windows for many years. 

Our windows combine state-of-the-art equipment and know-how, advanced technologies, and dedicated craftsmanship. We also offer all the most popular window styles, including double-hung windows, sliding, bay and bow designs, casement windows, patio doors, and custom windows. We install vinyl replacement windows with advanced insulating properties to significantly reduce heat transfer and potentially lower monthly energy costs. We also have a range of finance options to make your home remodeling project pricing affordable.

We are known for our consultative approach to home remodeling, which helps ensure you get the results you want, and for installing top-quality products. Window panes really are the eyes to the soul of your home. So don’t delay in booking a consultation with Remodel USA today!

Want more information? Read some of our customer testimonials

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To make Remodel USA, a customer and an employee-oriented company that delivers quality products on time, every time for a fair price.

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