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How to Measure the Jamb Width?

How to Measure the Jamb Width?

One of the many decisions you need to make when shopping for a new door is what size jamb to get. This is particularly important if you are considering getting custom doors for interiors

If you don't know how to measure the jamb width, don't worry! This blog post will show you how. With a few simple steps, you'll be able to get the perfect fit for your space.

Steps of Measuring a Door Jamb

The jamb is the frame that surrounds the door. It has several parts, including the stop, the sill, the transom, and the threshold. But how do you measure a door jamb? 

Step one: Measure the Jamb

When measuring a door jamb, you will need a tape measure to calculate the distance between the top and bottom of the jamb (not including the trim). This will give you the height.

You'll also need to measure the distance between the left and right sides of the jamb to get the width. Finally, use a ruler or a caliper to tape the thickness of the jamb. 

Make sure to write down the measurements so you don't forget them!

Step two: Measure Door Casing

Frame casings come in a variety of sizes, so it is important to have measurements before starting. But how do you measure a door jamb casing?

You will need to measure the distance between the frame and the drywall to determine the height and width of the casing. This has to be measured both inside and out, and the measurements may differ. In most cases, two to three inches of molding will suffice because there may not always be a gap to fill or the difference may be very little.

You'll also need to measure the thickness of the trim. To do this, simply use a ruler to measure the thickness of the trim.

Write these figures down too so you won't forget them.

Parts of Door Frame

Modern interior doors boast frames that are composed of several parts, all of which work together to support the structure and keep it in place. 

Components of a frame typically include the header, jamb, stop, sill, and threshold. 

The header is the horizontal beam at the top of the frame. It's typically the heaviest part of the frame and helps to bear the weight of the structure. 

The jamb is a vertical piece of wood that forms the sides of the opening. They provide support and stability for the frame. 

The stop is the horizontal piece of wood that forms the top of the opening. The sill is a horizontal piece of wood at the bottom of the frame. And the threshold is the piece of wood that is placed beneath the sill.

All these parts work together to help your door to function correctly.

What are Typical Door Jamb Sizes

You might be surprised to learn that there is no such thing as a "standard" door size. In fact, jamb sizes can vary greatly depending on the type of door you have, its size, and even its style. French doors for example can be quite tall.

However, typical sizes tend to range between:

  • 4 9/16" for a 2x4 frame with 1/2-inch drywall
  • 5 1/2" for thick drywall or stucco on a 2x4 frame
  • 6 9/16" for a block wall or a 2x6 frame

If you're trying to figure out what size jamb you need, then it's important that you learn how to measure a door jamb size using the tips above. This will ensure that the structure fits snugly into the jamb and that there are no gaps or spaces around it.

Final Words

It is important that you get your measurements right when looking to determine door jamb size for exterior or interior doors. If you get the size wrong, your door may be noisy, not close properly, and definitely result in poor insulation. 

According to the US Department of Energy, improperly installed doors can cause significant energy loss every year. It's therefore important that you get things right to avoid higher energy bills.

Now that you know how to measure a door jamb, why not get started with updating your entryways? 

Choose from the best selections on United Porte and breathe new life into your living space.


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