How long of rail do I need for a 42 inch barn door?

13 Apr.,2024

 

How big should my barn door be?

When buying a sliding barn door, a prevalent question is: how tall and wide should my barn door be? Most people do not know that measuring your door frame for a barn door is different from measuring for a regular swing door.

You will need a different size for a sliding door versus a traditional swinging door in the same size opening. 

Unlike swinging doors, where the door has to exactly fit the door frame, with barn doors, you will need a slightly larger door than the opening. Why? Because if you have a door that is the exact same size as the opening, you will have lots of light and sound coming through the edges of the door. And if your opening is irregular, it will be evident when the door is closed.

 

Consider Privacy

As mentioned before, it is essential to make the door overlap the opening to ensure privacy and aesthetics. We recommend adding at least one inch overlap on each side of the opening or molding. The more overlap you have, the less light and sound will come through the edges. 

 

How to determine your barn door width

To determine how wide your door should be, measure the opening from one side to the other.

If your door has molding frames, you will need to measure the distance between the outside edges of the molding.

Lastly, you need to add 2" (two inches) to your width measurement. The extra inches will ensure that you will have privacy and no gaps when closing your sliding barn door. 

 

Barn door width measurement example

Let's take a look at another example of how to determine the width of your sliding barn door.

In this example, the opening has no molding. The distance between the edges of the door opening is 36," and we will add 2" (two inches) to that measurement (one inch for each size): 36" + 2" = 38" 

In this example, the barn door should be 38" inches wide.

 

How to determine your barn door height 

To determine the ideal height for your barn door, you will have to measure from the floor to the top of the door opening. If your opening has molding frames, measure from the floor to the outside edge of the frame. Add one inch to your final measurement to find out the ideal height of your door. 

 

Barn door height measurement example

 In this example, the door frame has no molding. The distance from the floor to the top of the opening is 80". For the final measurement, we need to add one extra inch: 80" + 1" = 81" 

In this example, your barn door should be 81" tall.

Note: Keep it in mind that for proper operation, your barn door should be 1/2" above the floor. Don't forget to check your sliding hardware kit installation requirements.

 

How long Should My Barn Door Hardware Track Be?

Now that we know how to measure for a barn door, another critical question is: how big should your barn door track be?

Your track size should be at least double the size of your door width; this will ensure that the door will completely uncover the entrance when open. The correct measurement will also provide a smooth, effective, and safe operation of the door.

 

Barn door hardware track measurement example

In this example, the door is 38" wide. For the door to cover the entrance when closed, we need to make sure the track is at least double the door size: 38" + 38" = 76". 

For a door 38" wide, we will need a 76" long.

Note: Make sure you have enough wall space on the side of the opening for the door to open completely. 

Now you know how to shop for the perfect barn door! Take a look at our vast collection of sliding barn doors and barn door hardware kits!

What other barn door questions do you have? Let us know in the comments!

For all other Door Opening Sizes, use this formula to find the Recommended Minimum Rail Length

(Single Rails Only)

(Door Opening * 2) + 6"

(Round up to the nearest half-foot)

How long of rail do I need for a 42 inch barn door?

Rail Size Chart