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How to take accurate window measurements?

Taking accurate window measurements

Many people assume that buying windows for a house is a simple task. You just call a manufacturer, provide them with all the necessary details and that's all, the job is done. Unfortunately, that’s not the case. Buying the most fitting windows for a house is in our opinion a rather complicated process and taking accurate window measurements is one of the most important steps to make the whole experience as smooth as possible.

How poor measurements might affect your windows?

You should know, that even minor measurement inaccuracies (like 1 cm) might prove to be a huge problem in the future. Because you won't be able to get an accurate, airtight, and watertight seal. In other words, if the window was installed it could create an opening for insects, allow drafts to enter a home, increase humidity as well as the risk of mold and mildew, and could cause noise pollution to enter your household.

6 steps to ensure that your windows are accurately measured

Over the years many experts covered the topic of taking accurate window measurements. By analyzing this topic and thanks to our knowledge in this matter we were able to create these 6 steps. Following them will give you the best shot at making precise measurements.

1. Use metric not imperial

First of all, for anyone who would like to use the imperial metric system – it’s not a good idea. In this case, it’s best to take the measurements in millimeters, not in inches. Why? The reason is simple. The metric system is much more accurate. Furthermore, it removes any room for error when the window manufacturer is forced to covert your measurements.

2. Measuring the window hole

This is one of the most important steps. Hence, you should first step outside, then measure the height and width of the window hole. Please remember that height measurements must be taken from underneath any existing removable windowsills, as this will help to avoid any errors. If your property is rendered then you should take off a little of the render itself and measure the brickwork edge.

3. Measure brick to brick in at least three different places

One thing that you should keep in mind is the fact that not all openings are exactly perfectly square. Therefore, the bare minimum of measurements which should be taken is three: top, middle, and bottom for the height, and the same should be done for the width. This will allow your window manufacturer to have an accurate idea of the exact size of the space into which the finished product is supposed to fit.

4. A secret for taking accurate window measurements - deduct 30-50 mm

This might sound like a piece of odd advice, however, hear us out. You always need to subtract 30-50 mm from the final height and width measurements. Why? The answer is relatively simple. This is to allow for a small fitting allowance around the new frame which you are going to put into the hole when installing the window. Furthermore, it will allow for minor adjustments to make sure that the windows sit perfectly in the right position.

5. Never measure the old frame

It seems that in the process of taking accurate windows measurements, this is one of the most common mistakes. Ignore the old frame. Measuring it is pointless due to the fact, that you are going to throw it away anyway. Especially if you take into consideration the fact, that it might be warped, so the results might be wrong anyway. Measuring the window opening will always be your best bet.

6. Be sure about your measurements

This is the most important point in this discussion. Make sure to double-check, or even triple-check if you have to, that your measurements are 100% accurate. This is important because window manufacturers will not take responsibility for unfitting windows if the measurements turn out to have been incorrect. If you are not confident in your ability to measure the window openings correctly, you can always ask a professional for help.

You can ask your manufacturer or distributor to take the window measurements for you. Most companies will offer such services. Hence, you can easily utilize them for your benefit and not worry that the measurements are not correct.

Stick to the above guide and we’re sure that your window measurements and in turn your windows are going to be exactly right, allowing you to avoid any significant issues in the future.

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