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Should a Fireplace Mantel Be Wider Than the Fireplace?

A fireplace can easily become the focal point of a room if decorated properly. The beauty of a fireplace depends on the surrounding elements. The size of a mantel is very important in bringing out the right look for your room. 

Now, as you plan to install a new mantel for your fireplace, you might be in a dilemma regarding the size of it.

Should a fireplace mantel be wider than the fireplace?

A fireplace mantel should be wider than the fireplace. In fact, for a room to be aesthetically pleasing, it is imperative that the mantel is not smaller than the firebox, or else, it may look awkward. The mantel should be at least 3 inches wider than the firebox on each side. 

The mantel width can become a matter of real stress if you’re not sure about its sizing. Balance is very important when it comes to creating the perfect room. If the mantel is smaller than the firebox, it will look out of place and make the firebox appear awkward.

However, a mantel completes the fireplace. Without it, you will still have a fireplace that may also work great, but with the inclusion of a mantel, you can achieve the perfect outlook that will seem even warmer and comfier. 

It’s true that there’s no fixed size or design of a mantel that you should necessarily go for. The choice depends on the space and aesthetics of the room, the design of the fireplace, and your preference. But the right mantel can bring the best look out of your fireplace.

How wide should your fireplace mantel be? What size should a fireplace mantel be?

There’s no right width for a fireplace mantel. While it must be wider than the fireplace to look good, it can be as wide as you want if that goes with your room. It is considered that the mantel should be at least 3 inches wider than the firebox on each side

Generally, you can find fireplace mantels 6 inches or even more past the firebox and those look great. The wider the mantel, the better it will look. But of course, the width should match the structure and size of the room as well. 

Some rooms really complement exceptionally wide mantels, while some don’t.

4 factors to consider for mantel width

While the mantel should be placed at least 3 inches past the fireplace, there are some factors that you should consider for mantel width.

Firebox dimensions:

The dimension of the firebox will help you determine the width of the mantel. You can measure the dimension of your firebox to get a clear idea about how wide the mantel should be. The minimum width should extend past the firebox by at least 3 inches. 

Remember that wide mantels help the fireplace stand out even better. So don’t refrain from getting an even wider mantel. The common width of a fireplace mantel used by homeowners extends past the fireplace by 6″, 12″, and even more. 

To determine that, you should consider these other factors.

Dimensions of the area or materials surrounding the firebox:

The area as well as the materials surrounding the fireplace play an important role in determining the right width for the mantel. Usually, the area around the fireplace is made of fireproof materials that are included for safety precautions along with decorative purposes. 

The materials can include bricks, wood, or tiles. The mantel width should not be narrower than the fireplace surround or it won’t look pleasant. Make sure that the mantel is at least of the same width or more than the surround.

Hearth size:

If your existing fireplace has a floor area or hearth, you should consider the size of that to determine the mantel width. Similarly, if you’re building a new fireplace along with a hearth, it should play its role in determining the mantel width. 

Usually, it is better to keep the mantel width the same as the hearth width.

If your fireplace has an exceptionally large hearth, it is okay for the mantel to be smaller. A mantel that exceeds the hearth width does not look very pleasing. So either go for the same width as the hearth size or opt for a narrower span for the mantel shelf. 

Room size:

You must consider the room size before you decide on the mantel width. Consider the wall that the fireplace is installed in. Consider the placement and numbers of doors and windows in the room. 

The overall layout of the room should be taken into consideration to choose the right width for the mantel. Big rooms can look good with wide mantels. But smaller rooms may not look good if the mantel is too wide.

What is the clearance for a fireplace mantel?

Since the use of a fireplace involves fire and drastic heat, there must be some clearance regarding the use of different materials. General fire code states that a mantel made of combustible materials must be at least 6 inches away from the fireplace opening

The same distance applies to non-combustible mantels as well. Also, you should use a non-combustible material between the mantel and fireplace opening for safety. 

The code also states that for every 1/8 inch of protruding combustible material, you are bound to add an additional inch of clearance. 

How to size a fireplace mantel?

Sizing a fireplace mantel can be a bit tricky, but it’s not that difficult. There are three main measurements that you will need to properly size a fireplace mantel. 


You can measure the depth of a mantel starting from the back of the mantel. You have to start from the back edge and end at the face of the mantel. The depth of a mantel should be determined properly. A little bit of depth can allow you to decorate the shelf beautifully. 

But if the depth is too much, it can trap the heat from the fireplace which is unwanted. 


You can measure the width of a mantel starting from one end of the mantel to the other end of it. The width is the longest measurement of a mantel. For some rooms, you can go as wide as you wish to with the mantel and even cover the whole wall if it looks good. 

But for smaller rooms, you may have to choose the width carefully.


The height of a mantel actually measures the thickness of the mantel. You can measure it from the top edge of the mantel shelf to the bottom edge. The height of the mantel from the floor and the fireplace itself are also important.

Consider the arrangement near the fireplace to determine the height off the ground. An average fireplace mantel height is somewhere in between 4′-6′ above the ground. To get the right height, the room size should be taken into account.

How do you hang a floating mantel?

A floating mantel is quite easy to hang. Check out the following steps to do it at home. 

Mark the area where you will hang the mantel:

First, you should mark the area where you want to hang the floating mantel above the fireplace. Consider the room’s aesthetics as well as the height from the fireplace to determine the right height. 

If you are hanging it on a stone or brick wall, you will have to use masonry bits, hammer drill, and masonry lag bolts. To mount it on drywall, you will need to find the wall studs. For that, you will be using a drill bit and wall anchors. 

Measure the mantel size:

Next, you must determine the mantel size. Consider all the factors that are required to determine the right width, depth, and face height of the mantel. 

Add support by drilling holes in the wall:

As you’ve selected the position of the mantel, now it’s time to drill holes for the lag shields. Then you can install the lag bolts into the stone or brick. 

Measure and drill holes on the mantel:

You need to drill holes in the same points as the wall on the mantel. Measure carefully and drill the holes so you can start the installation.

Hang the mantel carefully:

Now all that’s left is holding the mantel in place and pushing it through the holes so it can be tightly secured in place.

Caulk the seam for a flawless finish:

This step is not mandatory. But for a flawless finish, you can caulk the seam to complete the task. Let it dry completely before you start decorating it.

Final Thoughts 

A fireplace mantel should be wider than the fireplace. It should be at least 3 inches past the firebox on each side. In fact, the wider the mantel is, the better. A wide mantel highlights the fireplace well. Also, if the mantel is narrower than the fireplace, it will look awkward.