100% secure
online shopping
On all orders!  
Continental US
Order online or call


Call Us Today!

The differences between masonry doors and doors for prefabricated fireboxes are visually minimal but necessary to meet air flow requirements set by fireplace manufacturers. Masonry doors are engineered to have tight tolerances to help prevent energy loss while the doors are closed when fire is slowing down. Doors for prefabricated fireboxes are specifically designed to allow air to pass through the door frame to meet manufacturer requirements and allow the firebox to stay at a safe operating temperature.

Don't have time to read this?
Snap a pic of your fireplace and we'll tell you what you have!


A common misconception is if there is stone, brick, tile, or rock around your fireplace, then it is a masonry fireplace. This is not true.  Many zero clearance fireplaces have brick, tile, rock, or stone exteriors.  It's what is on the inside that counts. Manufacturers have become very good at making pre-fab fireplaces look like they are masonry.

Take a look at all of the fireplaces below.  Can you guess which ones are zero clearance fireplaces?  Click on the images to get a closer look.




It was a trick question - because ALL of them are pre-fab fireplaces.

Please read through the information below to make sure you are not mistakenly ordering the wrong type of fireplace door.

We want you to be safe.


Masonry Fireplaces
Click here to learn how to measure your Masonry Fireplace.

Masonry Fireplace Chimney

• Requires a brick or stone chimney
• Generally built during the construction of the home.
• The fireplace's construction becomes part of the home's structure.
• Created from clay, rock, brick or glass.

Masonry Fireplace

Masonry fireplaces can accommodate a variety of fireplace doors. Aluminum fireplace doors and steel fireplace doors are available in many styles and finishes to accommodate nearly every décor and price range. From classic to contemporary, the possibilities are endless. Steel fireplace doors allow unlimited customization including arches and laser cut designs. Aluminum fireplace glass doors are made from extruded aluminum and can be formed with curves and radius for a truly unique look.

Masonry Fireplace

Masonry Doors:
All masonry fireplace doors or screens are designed to overlap (sit on the face of) the opening or inside(sit inside of the opening). Fireplace openings should meet the following requirements:

Masonry Fireplace

• Suitable mounting surface on top and bottom of opening
• Mounting surface must be level.
• Fireplace opening should be square and level. Doors are made square. Any out of square conditions on the opening will be exaggerated, or will prevent installation.
• When measuring the height, always make note of the lowest and highest point. Example: If the lintel bar is lower than the brick, it is very important to inform FireplaceDoorsOnline.com of this. This will affect whether the fireplace door will mount correctly.




Zero Clearance Fireplaces
Click here to learn how to measure your Pre-Fab Fireplace.

Zero Clearance Fireplace Chimney

• Known as factory built, zero clearance or pre-fab fireplaces.
• Factory built fireplaces are easy to spot. If your outside chimney is faced with the same siding material as your house, you have a factory built fireplace.
• Requires a steel pipe chimney
• Added to the home during or after construction.
• Typically installed inches from combustible material.
• Firebox manufactured from metal. If there is any metal around the fireplace itself, you have a factory-built fireplace.

Zero Clearance Fireplace

Factory-built fireplaces, also called " Zero Clearance" or ZC fireplaces, are designed to be built with very little clearance to combustible components of your home. They can do this because they have designed the fireplace so that cooling air insulates the hot firebox from the structure of the home. The glass doors must be designed to allow that cooling air to flow the way the firebox manufacturer designed it to flow. Gaps between the glass and frame vents exist on ZC doors to allow for this airflow.

Pre-fab Fireplace


Zero Clearance Fireplace Doors:
These doors fit inside the Zero Clearance (or prefabricated) firebox. Fireboxes are machine made, and tend to be square.

Manufactured Fireplace


Still as a precaution, measure the width and height on three places, as described in the Masonry Door measuring above, and use the smallest number to be submitted in your online order.




If you're still not sure what tip of fireplace you have, send us a:
Send us a Snapshot Quote!


Or call us at 1-877-373-6677!

If you are 100% sure of the fireplace you have, click on the appropriate picture below to start searching for the fireplace door of your dreams!

Masonry Fireplace Doors  Fireplace Doors for factory built fireplaces