How to Replace Damaged Bricks

Replacing damaged bricks on your home or building can seem like an intimidating task, but with the right tools and techniques, it can be accomplished by most DIYers. Properly replacing bricks helps restore the structural integrity and aesthetic appeal of your masonry. In this comprehensive guide, we will walk you through the entire process of replacing damaged bricks, from assessing the damage to finishing the repair.

Assessing the Damaged Bricks

The first step is to closely examine the damaged bricks and determine the scope of the problem. Consider the following when inspecting the bricks:

Location of the damage – Make note of where on your home or building the damaged bricks are located. This will help determine the best way to access and repair them.

Number of damaged bricks – Count the total number of bricks that need replacing. This will allow you to purchase the correct quantity of new bricks.

Type of damage – Look for cracked, crumbling, missing, or otherwise deteriorated bricks. This will indicate whether a simple replacement will suffice or if there are larger underlying issues to address.

Mortar condition – Check if the mortar around the damaged bricks is also deteriorated. Crumbling or missing mortar will need repointing after the bricks are replaced.

Structural issues – Determine if the damaged bricks are isolated incidents or signs of sinking, shifting, or other structural failures. Larger issues may require professional expertise.

Thoroughly inspecting the damaged bricks and surrounding area will provide the information needed to continue with the repair. If the damage appears extensive, consult a professional mason before proceeding.

Gathering the Right Materials

Replacing bricks requires a few specialized masonry tools and materials. Gather the following before starting your repair:

Replacement bricks – Match the size, color, texture, and shape of your existing bricks as closely as possible. Purchase from the same manufacturer if available. Get 10-20% more than needed to account for breakage and imperfect cuts.
Masonry chisel – A large cold chisel helps split whole bricks down to size. Look for one with a blade at least 1 inch wide.
Brick hammer – The Hammer ‘s flat blade end is used to chip away old mortar. The pointed end helps split bricks. Get at least a 3-pound hammer.
Mason’s trowel – A pointed trowel applies new mortar between bricks. Use a sturdy steel trowel with a triangular 4″ to 6″ blade.
Grout bag – To apply mortar in small spaces, use a grout bag fitted with a large tip opening. You can also use a standard zip top bag.
Masonry saw – For large repairs, a compact masonry saw neatly cuts bricks to size. Look for a 4 1⁄2 or 5-inch diamond blade.
Mortar mix – Use a premixed Type N or Type S mortar that matches the strength and color of the existing mortar.
Safety gear – Wear safety goggles, dust masks, heavy work gloves, and ear protection when cutting bricks.

Having the right tools and supplies on hand will make replacing damaged bricks much simpler. Avoid improvising with inferior equipment.

Removing the Damaged Bricks

Once you have thoroughly assessed the damage and gathered supplies, it’s time to start removing bricks. Take care not to damage surrounding bricks during removal. Follow these steps:

1. Clear the area – Remove any obstructions from the front and back of the repair area. You’ll need ample working room.

2. Outline the damaged section – With a pencil or chalk, mark the perimeter of bricks to be removed. This helps avoid over-cutting.

3. Chisel inward from edges – Use the masonry chisel and hammer to chip away the surrounding mortar, working inward from the edges.

4. Extract whole bricks first -Try to remove any intact bricks before broken sections. Extract them carefully to avoid damage.

5. Split partially damaged bricks – Use the chisel and hammer to split any broken bricks so they can be removed easily.

6. Remove all debris – Clear away all loose brick and mortar pieces. Use a shop vacuum for small dust and particles.

7. Wipe the area clean – Use a damp cloth or brush to wipe away any remaining dust and particles from the cavity.

Take time to cleanly remove all damaged brick and mortar before moving on to the next stage. Any debris left behind can weaken the repair.

Cutting Replacement Bricks

In most cases, you’ll need to cut replacement bricks down to size to fit in the repair area. Measure precisely and use a masonry saw or chisel to get a close fit:

For small repairs, score the desired cut line with the chisel’s edge, then strike firmly to split the brick.
For large areas, mark cutting lines with a pencil. Use a masonry saw fitted with a diamond blade to slice bricks cleanly.
Cut bricks 1/8″ smaller than needed to allow space for mortar between bricks. Test fit each cut brick.
Cut replacement bricks to interlock with existing brick patterns for the best structural integrity.
Wear safety goggles, gloves, and a dust mask when cutting bricks. Keep hands clear of the blade.
Use a saw with a water attachment to keep dust at a minimum.

Accurately sizing and cutting replacement bricks helps the repair blend into the existing masonry. Taking proper safety precautions reduces the risk of injury from sharp and flying debris.

Installing Replacement Bricks

Once the damaged bricks are removed and replacements are cut to fit, it’s time to set the new bricks into place:

Lightly dampen the repair cavity and new bricks with water before installation. This helps the mortar adhere.
Use a mason’s trowel to apply a layer of fresh mortar 1⁄2” to 1″ thick where the next brick will sit.
Set the replacement brick into the mortar bed. Position it evenly with surrounding bricks.
Apply pressure and a slight twisting motion to work the brick into the mortar for a secure bond.
Use a level to ensure the new bricks sit flush with existing rows. Adjust as needed while mortar is still soft.
Fill any gaps around the bricks with mortar using a grout bag or trowel. Strike flush with the face of the wall.
As you work, scrape away excess mortar and keep bricks clean using a trowel or wire brush.
Allow mortar to fully cure for a few days before final cleaning and sealing.

With care and patience, the new bricks should set tightly in place, securely bonded to the surrounding masonry.

Repointing Mortar Joints

Replacing damaged bricks often requires repointing the joints between the bricks for a seamless repair. Follow these tips for repointing with fresh mortar:

Use the mason’s hammer and chisel to clear away old, cracked mortar to a depth of 1⁄2” or more until you reach solid material.
Brush or vacuum away all loose debris and dust.
Dampen the joint cavities before applying new mortar. This helps adhesion.
Fill joints with fresh mortar using the grout bag. Aim for a compact, consistent fill.
With a trowel, strike off excess mortar so it’s flush with the brick edges.
When mortar becomes crumbly, run a metal striking tool along joints to compress and smooth them.
After mortar dries, brush the joints to remove dried excess mortar.
Apply a final brushing 1-2 days later once mortar has fully hardened.

Repointing provides an attractive finish and seals joints against water penetration. Take care to match the original mortar style.

Finishing Touches

Once the brick replacement is complete, there are a few finishing steps to blend it seamlessly with the existing wall:

Clean the repair area – Use a stiff masonry brush and water to remove all dried mortar and dust from replacement bricks and surrounding masonry.
Seal the mortar – Apply a masonry sealer to the joints according to manufacturer directions. This prevents water damage.
Color touch-up – Dab on mortar coloring with a paintbrush to help new mortar blend with old. Match the original hue.
Paint sealant – Coat replacement bricks with a masonry paint or sealant to match the color and texture of the original bricks.
Inspect your work – Look over the repair area to ensure the new bricks blend seamlessly with the old in all aspects – color, alignment, mortar style, etc.

With attention to detail on cleanup and blending, the brick replacement should be practically undetectable compared to the original wall. Taking time with finishing ensures a durable, seamless repair.

How to Replace Damaged Bricks: FAQ

Replacing damaged bricks on a masonry wall or structure? Here are answers to some frequently asked questions about completing a successful DIY repair:

How do I match old bricks when purchasing replacements?

Closely examine the size, shape, color, texture, and thickness of the original bricks. Take a sample with you when shopping for the closest match possible.
Check with the local brick supplier to see if they have bricks from the same or similar batches. Manufacturing details often leave distinguishing marks.
If unable to find an identical match, choose replacement bricks in a close shade. Use coloring agents and sealants to blend them after installation.

What mortar mix should I use?

Inspect the original mortar for the mix ingredients, usually sand, lime, and cement. Attempt to get a similar premixed mortar blend.
Type N mortar provides medium strength for above-grade exterior walls. Type S mortar offers higher strength for below-grade use.
Be sure to match the mortar color as well. Add mortar pigments if needed to achieve the original hue.

How long does the mortar need to cure before finishing?

Allow fresh mortar to cure for 2-3 days before final tuckpointing and cleanup. This ensures an adequate bond while still soft enough to tool smoothly.
Wait 5-7 days before applying any sealants or color agents to the repaired area. Mortar will fully harden within 28 days.

What causes bricks to deteriorate prematurely?

Repeated exposure to moisture from rain, sprinklers, etc. can damage brick and mortar over time. Good drainage and proper sealing helps prevent deterioration.
Freezing temperatures and thaw cycles can crack bricks, especially in colder climates. Keep walls properly sealed against water penetration.
Poor original materials, like low-fired bricks or weak mortar, may fail sooner than quality materials. Using the proper regional materials can extend the lifespan.

When should I call a masonry professional instead?

For any signs of sinking, shifting, or structural instability, contact a mason to inspect for underlying issues before attempting repair.
If the repair area involves an arched entryway or structural feature, have a professional handle the brick replacement and modifications.
For multistory buildings or repairs over 20 feet tall, consider scaffolding and harness precautions a professional is better equipped for.

Conclusion

With the right tools and preparation, most damaged brick replacement projects can become DIY repairs. Always begin by thoroughly assessing the damaged area to determine the scope and requirements of the repair. Be sure to gather quality matching bricks and mortar along with masonry-specific tools for cutting, chiseling, and shaping replacement bricks.

Carefully follow the steps to remove damaged bricks, cut replacements, repoint mortar joints, and blend the repair area into the existing wall. With diligence and proper technique, the finished result should withstand the elements and pass as original construction for decades to come. Periodic inspection and timely repairs help preserve your masonry’s longevity and aesthetic appeal.