The Most Important Parts of a Front Door


The Most Important Parts of a Front Door

Your front door is more than a door—it’s a whole system. There are many connecting parts that work together to create a strong barrier against intruders as well as elements like air and water. However, the names of these various components can make things a bit confusing when it comes time to replace your door.

Here’s a quick list of the most important parts of a front door that may impact your search for a new one. 

Parts of a Door

Parts of a Door

1. Transom

The window above the door. If you must replace your door, it’s important to keep the design of your current transom glass in mind to ensure an overall cohesive look. Many Masonite glass designs are available with matching transoms.

2. Door Frame or Door Jamb

The side jambs, head jambs, and mulls parts that make up the frame. The size of the frame determines the size of the door that fits in it. Door frames (also called door jambs) are also relevant to your search for a new door due to aesthetic and performance purposes. They can be made of wood or aluminum and can be ordered primed and ready to paint or pre-finished to blend in seamlessly with whatever door you choose.

 3. Mull Post

The structural post between the sidelite and the door, which means you only need to worry about this component if you have sidelites.

4. Door Slab

The door panel itself. Exterior door slabs are made from wood, fiberglass or steel. Each material offers its own unique benefits. Learn more about which door material may be right for you.

5. Sill

A horizontal beam below the door that supports the frame, prevents the door from swinging through and keeps the elements out. This part of the door is sealed, fastened to the floor and then covered with a threshold to protect against the elements and general wear and tear.

6. Sidelite

A fixed narrow panel, usually glass, installed next to an exterior door panel for decorative purpose. Just like with a transom, many Masonite glass designs are available with matching sidelites.

7. Brickmold

The molding around windows and exterior door frames on the exterior-facing material of the building. It serves as an aesthetic boundary between the siding and the frame and is mostly used in pre-hung units.  

Knowing these main door parts will make it much easier when shopping for your new system or talking with a pro about your project.  For more information or specific questions, connect with a Masonite dealer near you.

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About Masonite

At Masonite, we create Doors That Do More™ to enhance the spaces where our customers live, work, heal and learn. Our beautiful, durable doors are environmentally responsible and are designed to provide more light, sound control and protection.


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