How to Repair Cracks Inside Fireplaces?

If you own a fireplace, you may have noticed some cracks or holes in the mortar that surrounds the bricks. The mortar is the original material used to build the fireplace. You can fix these small cracks by simply replacing the mortar, but larger and deeper cracks require a more sophisticated approach. 

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First, determine the size of the crack. Larger cracks can allow the flames to penetrate to combustibles and cause damage. This is particularly the case with wood burning fireplaces. However, even a small hole can pose a fire hazard. 

Next, determine whether the mortar is the correct material for the job. Some materials, such as acrylic mortar, are better suited for the job. Aside from the obvious reason of making the repair easier, the acrylic mortar will not stick to the soot surface. Instead, it can help keep embers from igniting the soot. 

Once you know what material you need to replace the mortar with, you can move on to patching the hole. This can be a do-it-yourself project, or you may want to hire a professional. Most do-it-yourselfers will remove the old panel and replace it with a new one. It’s also a good idea to ensure the new panel will fit snugly against the other panels in the fireplace. 

Before starting your repair, make sure the mortar is cleaned off and dry. Use a shop vacuum to get rid of any dirt or debris that has accumulated over time. Cleaning the mortar is also important because it will help you to see if any of the material has broken off. 

Next, apply the proper type of fire cement. This is a specially designed material that withstands the high temperatures of a fireplace. Depending on the product you use, you will need to wait a few hours to allow the material to harden. 

Next, consider the appropriate width of the mortar joint. Mortar joints that are too wide can cause cracks. There are some special high-temperature caulks that you can purchase to repair small gaps. 

Finally, you’ll need to use the proper tools. Having the right tools will enable you to complete your fireplace repair in a matter of minutes. While you’re waiting for your replacement to arrive, don’t try to move the fireplace yourself. Ideally, it should be placed on a strong foundation. Otherwise, you risk having it shift around, causing the mortar to fail. 

In all likelihood, you’ll be able to enjoy your fireplace in about 24 hours after completing the repair. However, if your cracks have been left unattended for some time, you may need to wait a week or more before you can light your fireplace again. When repairing a fireplace, it’s always a good idea to check it in the morning before lighting a fire. 

Although a fireplace may need to be repaired from time to time, it’s usually not too difficult to do. It’s important to take care of any issues that arise while they are small so you can keep them from getting worse.