Signs That Mortar Joints Need Repair or Replacement

What are mortar joints?

Mortar is the material used between bricks or stones during masonry construction. It serves to seamlessly join individual units together, providing a weather-resistant layer.

There are several mortar joint profiles used in brickwork, including flush joints where the mortar is level with the bricks, raked joints that are recessed, and struck joints with a raised profile. Cement, lime, sand, and sometimes other additives like brick dust or polymers are commonly blended to create mortar mixes. The type of joint style and formulation used affects how porous the mortar is and how quickly it weathers over time.

Common Causes of Mortar Joint Deterioration

Weather and Environmental Factors

Those living in Fredericton know that the city experiences significant freeze-thaw cycles throughout the winter months when temperatures can drop below freezing for weeks at a time. If your home is in Fredericton, you are all too familiar with how moisture gets trapped in materials like mortar during the winter.

The fluctuating temperatures mean that water in the pores of mortar joints will expand and contract, which can cause small cracks to form. Over many years, this freeze-thaw activity contributes to flaking and damage in mortar.

With Fredericton’s location near the Saint John River as well, high moisture levels mean rain and groundwater are common even after snow melts in the spring. This prolonged exposure allows water to slowly erode and break down the cement in mortar over decades.

Fredericton’s climate also means mortar may be subjected to more ultraviolet radiation from sunlight. The UV exposure can negatively impact some mortar formulations by degrading the bonding material over extended periods outdoors.

Age and Wear

As a masonry wall ages, normal settling of the foundation may put stress on mortar joints, causing fine cracks or separations to form. General wear can gradually deteriorate surface mortar faster than interior joints as well.

Poor Initial Construction

Mortar that was hastily mixed, not given enough time to cure before use, or laid improperly will break down quicker when environmental stresses are applied. Low-quality aggregate or excess water content leads to a weak mortar mix.

Structural Movement and Stress

Seismic activity, shifting soils, or wood framing problems that put undue pressure on a masonry wall can crack otherwise durable mortar joints over the long run. Nearby construction work may introduce harmful vibrations.

Key Signs Mortar Joints Need Repair or Replacement

• Crumbling or Powdery Mortar – Failing mortar often first appears as sand or small flecks of cement sloughing off near cracks and joints. Brushing with your hand leaves behind a powdery residue where the cement binder is deteriorating.
• Visible Cracks and Gaps – Small hairline cracks may be superficial, but cracks wider than 1/16 inch often penetrate deeper. Look for horizontal or vertical cracks across multiple courses of bricks, indicating structural settlement issues.
• Loose or Falling Bricks – Unsecured bricks that rock or are loose in the wall may soon detach completely under weather exposure, causing damage or safety hazards.
• Water Infiltration – Areas of darker mortar that seem wet long after rainfall indicate absorption problems. Look for interior damp spots or efflorescence as well.
• Discoloration and Staining – Surface stains may be superficial, but widespread or penetrating discoloration could suggest underlying deterioration.

How to Repair Damaged Mortar Joints

For minor repairs like small cracks or isolated loose bricks, a DIY repointing kit can work well if you follow directions carefully. But widespread damage or signs of structural issues demands a mason’s expertise to ensure the fix is long-lasting. They can properly remove loose or disintegrated mortar before filling and tooling new mortar joints.

Professional brick repointing helps prevent moisture penetration and further deterioration. For very large cracks, severe spalling, or other extensive signs of failure, partial or full replacement of defective areas may be necessary instead of repair alone. Taking prompt action when warning signs first emerge helps avoid costly reconstruction work in the future.

Preventative Measures and Maintenance Tips

While wear and tear on mortar over decades is inevitable, regular maintenance can slow its effects:

• Inspect brickwork and caulk or repoint as needed every 7-10 years depending on weather exposure.
• Ensure water drains away from the foundation with good grading and intact gutters/downspouts.
• Seal any cracks above grade to prevent moisture from being absorbed deep into the wall.
• Apply a breathable water proofer or sealant to exterior mortar joints about every 5 years.
• Monitor for plant growth too close to the structure, which can promote moisture problems.

Call the repointing experts in Fredericton

If you’ve identified signs that your home’s mortar joints need repair or replacement, it’s time to call the repointing experts in Fredericton. One of the most trusted names for quality masonry services is Atlantic Brick and Stone.

As a leading repointing contractor in the area, we have decades of experience providing expert tuckpointing, brick repair, and masonry construction services. Our trained team of masons can properly evaluate the condition of your brickwork, propose a tailored solution, and complete all work to high standards.

To discuss your project and get an estimate for repairs from the best repointing specialists in Fredericton, contact us for all your masonry needs. Our masonry repairs are backed by strong warranties.

To Close

• Watch for crumbling or powdery mortar, cracks over 1/16 inch, loose bricks, or water stains as signs a mason should evaluate the brickwork.
• Having a mason assess the damage can help determine if repair or replacement is needed.
• Addressing issues early avoids more serious problems developing that require costlier fixes like partial brick replacement later on.
• With routine maintenance like inspections and repointing, the masonry can stay structurally sound and protected for decades.

FAQs about damaged mortar joints

What does bad mortar look like?

Bad mortar may appear crumbly, powdery, cracked, or discolored. It can fall out easily when pressed or scraped with a tool. Sections may be soft, friable, or out of place compared to adjacent intact areas.

What is the lifespan of mortar?

The typical lifespan of mortar is at least 30 years when properly applied and maintained. Mortar exposed to harsh weathering will deteriorate faster, often over 17-20 years.

Will new mortar stick to old mortar?

New mortar will generally bond well to sound, intact old mortar. But if the old mortar is degraded, repointers must remove and replace it a few inches into the joint to ensure strong adhesion of the new mortar applied. Proper surface preparation is key for bonding.

What happens if you don’t repoint?

Failing to repoint deteriorating mortar joints can cause several issues over time for the brick structure. Moisture is able to penetrate deeper into the bricks, and freeze-thaw cycles will worsen, expanding cracks in the mortar. Individual bricks may shift or fall out of position within the wall. Interior walls of the structure could be damaged by leaks developing through cracks.