Are You Using the Right Refractory Mortar Product for Your Project?

October 29th, 2015

For more than 40 years, Heat Stop products have been used across the country. As the years have progressed, we have added several Heat Stop products to the mix; however, using the right Heat Stop refractory mortar product is critical to the success of your project.

Are you using the right Heat Stop product?

With such a range of products available, it can be easy to confuse Heat Stop mortar products' intended uses with the uses of Heat Stop castable products — or even other homemade formulations (including fireclay).

Why it's important to choose the right Heat Stop product

It's extremely important to choose the right Heat Stop product for your projects. Heat Stop products that are not applied correctly may not achieve the intended results. Here's an example: Heat Cast 40 is a castable product intended to be used instead of firebricks or to make special shapes. It should be applied 2" thick. If it is not applied thick enough, it may not be structurally sound for the intended application. Applied correctly, it is of course a very sound product.

Similarly, Heat Stop premixed or Domestic Fireplace Mortar are products intended for interior (no moisture) applications. Using them in high moisture applications may not achieve the intended results. For exterior applications, it's important to only use Heat Stop 50 or Heat Stop II.

Top usage mistakes with Heat Stop products

Choosing the right product is essential, but once you have the right product for your project, proper usage ensures the success and safety of your project. Here are the top three usage mistakes to avoid with Heat Stop products:

  1. Not mixing the Heat Stop premix or Domestic Fireplace Mortar products thoroughly before use. Just because they are labeled "premix" doesn't mean they couldn't use a little stir!
  2. Making mortar joints too thick when applying Heat Stop premix or Domestic Fireplace Mortar (joints should be 1/16" - 1/8")
  3. Using premix products (Heat Stop premix or Domestic Fireplace Mortar) for interior applications.

When using Heat Stop products, be sure to understand the building codes in your area, and follow them. Pay special attention to codes that require the use of refractory mortar (code ASTMC-199), and learn about good quality masonry practices. Follow these suggestions and avoid the mistakes noted above, and your project will be on its way toward successful completion.

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