Masonry Fireplace Accessories: Firebrick & Mortar

FireRock Adhesive Mortar for firebrick applicationFireRock Adhesive Mortar

FireRock Adhesive Mortar must be used to install the firebox in order for the FireRock warranty to be valid. It may also be used to install the firebrick, though substitutions are allowed. Substitutions in the firebox will result in a non-compliant unit and will invalidate the FireRock warranty.


  Weight per bag: 25 lbs

  Bags per pallet: 96 bags

  The appropriate number of bags for each fireplace are included with the installation kit

  Mortor for masonry chimney block must be purchased separately

  One bag of mortar is needed for every 6 masonry chimney pieces



Mix mortar with water to a trowelable consistency. Mix at a low speed to avoid entraining excess air into material.



  Mix mortar with water until smooth and without dry spots (see instructions on bag)

  Apply sufficient amount to surface to ensure 100% coverage is obtained

  Must use FireRock Adhesive Mortar to erect all FireRock firebox and chimney components

  After setting of a component, the mortar must be able to be seen at the surface of the joint and subsequently smoothed

  Do not apply if temperatures are below 40 degrees F

  Under normal conditions assembly is cured in 24 to 48 hours

  See our maintenance tips for wear & tear


Firebrick options for FireRock fireplacesFirebrick Colors & Sizes

Firebrick used must comply with ASTM standards C1261 and C27 and meet or exceed the requirements of local, national and international building codes regarding fireplace and chimney construction and the National Fire Protection Association NFPA-211. A compliant firebrick lining is 1 ¼” or 2 ½” thick. Although you can use either firebrick thickness to line the sides, back and floor of the firebox, FireRock recommends using the 2 ½” thick firebrick to line the floor and ¼”on sides to provide true opening size.


  For your convenience, FireRock stocks firebrick in 3 sizes and two colors to accomodate the most popular firebrick patterns (Running Bond, Stacked Bond, Basket Weave, Full Herringbone, Split Herringbone)

  Available colors include Red and Buff

  Full Firebrick dimensions: 4” (W) x 9” (L) x 2 ½” (D)

  Split Firebrick dimensions: 4” (W) x 9” (L) x 1 ¼” (D)

  Soaps (Buff color only): 2 ¼” (W) x 9” (L) x 1 ¼” (D)



Firebrick popular pattern options for FireRock fireplaces

Click to View Other Masonry Fireplace Accessories:

Installation Kits  |  Outside Air Kit  |  Solid Chimney Block   |  Chimney Pots

Offset Blocks   |   Metal Chimney System   |   Height Extension Kit   |   Bricking Flange

Not sure what direction you want to take with your next project? Contact us to learn from our experts.

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