7 Expert Tips for Measuring for Replacement Windows

7 Expert Tips for Measuring for Replacement Windows

February 27, 2018
By:
Martin Whitmore, President of US Window & Door
7 expert tips on replacing windows

The easiest way to get a new window is to do a pocket replacement. This means you replace your old window with a new unit that is exactly the same size, and you’re usually able to leave the window trim just how it is. In any case, it’s important that you get it right when measuring replacement windows.

Of course, this depends on how your window is made. In some cases, you may have to remove the trim so you can get a proper measurement.

Now, measuring your window is pretty straightforward, but there are some tips you need to know to make sure you don’t end up with the wrong measurements. There’s nothing worse than measuring your window, buying a replacement, and finding out it’s too big.

So make sure you read through these seven tips before you start measuring for replacement windows.

How to Start measuring for Replacement Windows

These next few tips will show you the best way to measure a window so you don’t have to worry about doing it wrong. Remember to measure slowly. It’s okay to start over if the numbers aren’t turning out quite how you think they should.

Tips on Measuring Replacement Windows

1. Go With the Smallest Measurement

You have to measure your window from a few different angles to make sure you get the right size for your replacement. And you’ll probably end up with slightly different numbers for each one.

Slightly different numbers are okay, but if the numbers are wildly off, you should probably remeasure. The numbers should always be very close to each other.

The smallest number of your measurements should always be the number you choose for the overall measurement. This way you’ll know the replacement will fit even in the smallest places.

2. Measuring Replacement Windows: Do It Three Times Over

This doesn’t mean measure your windows in three different spots (though you should do that too), this means measuring your windows a total of three times.

If you measure incorrectly once, one of the other two times should help you catch your mistake.

But don’t just measure the first time and speed through the next measurements. Take your time and act like you’re starting over from scratch. You won’t catch any mistakes if you aren’t really paying attention.

3. Measuring Replacement Windows for Width

When you’re measuring for replacement windows, grab a tab measure and start with the width.

Place one end of the measuring tape against the window jamb and measure all the way to the other jamb. Do not measure from the stop mold or the parting bead. These will likely be removed and replaced along with your window.

You may need to remove the interior window trim to accurately measure the from jamb to jamb, but in most cases, you shouldn’t have to.

In total, you should take three measurements of the window’s width: at the bottom, at the middle, and at the top. When you’re finished measuring (remember to do all three measurements three times), take the smallest number.

4. Measuring Replacement Windows for Height

To measure the height of a window, use your measuring tape to measure from the windowsill to the top window jamb. Don’t confuse the windowsill with the window stool.

The windowsill is the board the window closes over. The window stool is a fancy interior molding that makes the window look nice and finished.

Keep in mind, the middle of the windowsill usually slopes slightly away from the house so dirt and water will fall back outside. So when you measure the height, make sure you measure as close to the edges as possible.

You should still measure the middle of the window too, but don’t be surprised if that measurement is a little bigger than the others.

In total, you should measure the height of your window on both sides and in the center.

5. Measuring Replacement Windows for Depth

This refers to the rough window opening. Use your measuring tape to measure between the outside and inside stops. This measurement could be as small as 1/4 of an inch or, depending on the window, a bit larger.

You may not necessarily need this measurement to get a window replacement. Talk to your service provider and ask if they need it before you get started. If you aren’t sure whether you’ll need the measurement or not, it’s a good idea to measure it anyway.

It’s better to have the information just in case instead of putting your window replacement on hold to go back and get it.

6. Once You Have All the Measurements, Make Them Smaller

This will make it easier for professionals to install your replacement window.

You don’t necessarily have to do this, but some professionals prefer it. Ask them if they recommend reducing the measurements before getting your replacement windows.

If they do recommend making the measurements slightly smaller, you should take away no more than 1/4 of an inch from the width and 1/2 an inch from the height. Any more and you replacement may not fit properly.

7. Don’t Take Out Your Current Window When Measuring for Replacement Windows

Some replacement windows have to be custom made, so if you take out your window to measure, you could be without a window for a very long time.

If for some reason you have to remove your window before you can make measurements, make sure you have some sort of backup plan.

Measuring Replacement Casement Windows

When You’re Measuring for Window Replacements, Double Check Everything

This means the measurements, the type of window you need, and if your replacement needs to be custom made. If you take out your window and the replacement doesn’t fit, you’ve got problems. Living without a window is essentially the same as living with a giant hole in your wall, and that’s not very pleasant.

And make sure you measure all your windows that need replacements. Don’t just assume one window is going to be the same size as all the others, even if it should be. Again, it’s better to be safe than sorry.

Are you ready to get some new windows? Take a look at some of the windows we offer!