How to Repair a Vertical Crack in a Brick Chimney Wall

Sometimes unsightly vertical cracks may appear in your brick chimney walls. Don’t despair, as long as you are not afraid of heights the cracks are relatively easy to repair. Here’s how:

Materials Need to Repair a Vertical Crack in Brick Chimney Walls

In order to repair vertical cracks in brick chimney walls you will need to first gather together the following materials;

1 roll wide duct tape, heavy duty
1 pair scissors
1 large bucket and stirring stick
1 bag brick mortar
1 plastic funnel
1 large piece of pressed board (to serve as a brace)
1 wooden 2 by 4 (to serve as a brace)
1 box nails
1 hammer
1 pointed trowel
1 square trowel
1 medium size paint brush
1 pair work gloves
1 pair safety goggles

Step 1: Cleaning and Preparing the Vertical Crack for Repair

Clean the vertical crack by removing any loose brick and mortar. You may need to use a pointed trowel or paint brush to do this. Once the vertical crack has been properly cleaned, cover three feet of the bottom portion of the crack with heavy duty duct tape. The duct tape will help hold the brick mortar in place while it dries so you will want to make sure that the tape is well secured to the bricks. Continue by taking out your large bucket and preparing the brick mortar according to manufacturer’s instructions. You will, however, want to make sure that the brick mortar is runny enough to be poured through the funnel and down into the crack.

Step 2: Pouring the Mortar into the Vertical Crack

Carefully place the funnel at the top of the duct tape seam and hold it into place as you pour the brick mortar into the funnel and down into the vertical crack. It is important to note that despite the heavy duty nature of the duct tape, it is not recommended to repair more than three feet of vertical crack at a time. Therefore, if the vertical crack in your brick wall extends over three feet in length, you will need to repair the crack in segments.

Step 3: Finishing the Repair

Using the hammer, nails, wooden two by four and pressed board, construct a vertical brace. Buttress the wooden brace up against the duct taped repair area and allow it to sit like that undisturbed until the mortar sets. Depending on the brand of brick mortar used, this may take up to four hours. In the advent of a vertical crack that is over three feet long, once the mortar used in the first three feet of repair has set, you may continue filling the hole by repeating the above steps. Once the entire crack has been filled and the mortar has cured, the wooden brace may be removed.

My husband and I are homeowners and have a history of buying and renovating properties. We tend to do all of the renovations and repairs ourselves.

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