Mortar joints make up a noticeable part of every brick wall’s surface. They hold the bricks together, spread the load and keep water out – and on exposed walls, they shape the final look. Understanding brick mortar joints helps you get a wall that is both strong and attractive.
What is a Mortar Joint?
A mortar joint is the layer of mortar between bricks. There are two main kinds:
- Bed joints: horizontal joints on which bricks are laid
- Perpend (head) joints: vertical joints between bricks in the same course
A typical joint thickness in Indian brickwork is about 10 mm. Uniform bricks make it easier to keep joints thin and consistent.
Common Types of Brick Mortar Joints
| Joint Type | Appearance | Weather Resistance | Best Use |
|---|---|---|---|
| Flush | Level with brick face | Moderate | Walls to be plastered or painted |
| Concave (bucket handle) | Curved inward | Very good | Exposed exterior walls |
| V-joint | V-shaped groove | Very good | Exposed walls with sharp lines |
| Weathered | Sloped downward outward | Very good | Exterior walls in rainy areas |
| Struck | Sloped inward at the bottom | Poor outdoors | Interior walls |
| Raked (recessed) | Set back from face | Lower | Decorative walls, shadow effect |
| Beaded | Raised bead | Moderate | Decorative and heritage work |
Flush Joint
Mortar is cut level with the brick face. Simple and quick, but not the most water-resistant, so it is often used where walls will be plastered.
Concave Joint
Formed with a curved jointing tool that compresses the mortar. It sheds water well and is one of the most recommended joints for exposed brickwork.
V-Joint
A V-shaped tool creates a sharp groove. It sheds water well and gives crisp shadow lines.
Weathered Joint
The mortar slopes so the top edge is set back and the bottom is flush, helping rainwater run off.
Struck Joint
The opposite slope of a weathered joint. It can hold water on the ledge, so it is better for interiors.
Raked Joint
Mortar is removed to a small depth, creating strong shadow lines that highlight each brick. It looks striking but can collect water, so it needs dense bricks and good workmanship outdoors.
Choosing Joints for Exposed Brick Walls
- For exterior walls in heavy rain, choose concave, V or weathered joints.
- For interior feature walls, raked or flush joints give different visual effects.
- Match mortar colour to the bricks for a uniform look, or contrast it to highlight the pattern.
Get design ideas from our exposed brick wall design ideas and see finished work on our projects page.
Common Site Mistakes with Mortar Joints
1. Using Dry Bricks
Very dry bricks suck water out of the mortar, weakening the bond. Wet bricks appropriately before laying as per your engineer’s instructions. Learn why bricks are soaked in water before laying.
2. Thick or Uneven Joints
Joints much thicker than needed weaken the wall and waste mortar. Uneven bricks are a common cause, so choose uniform wire cut bricks.
3. Unfilled Vertical Joints
Leaving perpend joints half-empty lets water in and reduces strength. Every joint should be fully filled.
4. Retempering Old Mortar
Adding water to mortar that has started setting weakens it. Mix only what can be used in time.
5. Wrong Mix Ratio
Too little cement weakens the wall; too much can cause shrinkage cracks. Follow the specified ratio. See how much cement and sand is required for 1000 bricks.
6. Skipping Curing
Brickwork should be kept moist for several days so the mortar gains strength.
7. Mortar Smears on Exposed Bricks
Wipe off extra mortar before it hardens. For cleaning later, see how to clean exposed brick walls.
8. Tooling at the Wrong Time
Tool joints when the mortar is thumbprint-hard, not too wet and not fully set.
Mortar Joints and Brick Bonds
The joint type works together with the bond pattern. English and Flemish bonds show off neat joints, while stack bond relies on perfectly straight joints. Learn more in our guide to brick bond types and brick arch designs.
Why Mahaluxmi Bricks?
Neat joints begin with good bricks. Mahaluxmi Bricks, established in 1982, produces uniform, sharp-edged bricks that make thin, straight joints easy to achieve. Explore our hand moulded bricks, brick collection and full product range.
Final Thoughts
Brick mortar joints are much more than filling between bricks. The right joint type protects your wall from water and improves its appearance, while good site practice keeps it strong. Choose the joint to suit your wall, avoid common mistakes, and use quality bricks for long-lasting masonry.
Contact Mahaluxmi Bricks
Looking for premium-quality bricks for your next project? Explore Mahaluxmi Bricks, a trusted brick manufacturer in India, or contact us for a free quote.
Email: mahaluxmibricks@gmail.com
Address: HVQ3+2Q8, Derabassi – Barwala Rd, Bhagat Singh Nagar, Dera Bassi, Punjab 140507
Phone: 098888 06069
FAQs – Brick Mortar Joints
1. What is the standard thickness of a brick mortar joint?
A joint of about 10 mm is typical in Indian brickwork, though your specifications may vary slightly.
2. Which mortar joint is best for exterior walls?
Concave, V and weathered joints are best for exterior walls because they shed water effectively.
3. Why do mortar joints crack?
Common reasons include wrong mix ratio, dry bricks, poor curing, retempered mortar and structural movement.
4. What is a raked joint?
A raked joint has mortar removed to a small depth, creating shadow lines. It looks attractive but can hold water, so it needs care outdoors.
5. When should mortar joints be tooled?
Tool joints when the mortar is firm enough to hold a thumbprint but has not fully set.
