Brick masonry is a traditional construction technique that relies heavily on the style and strength of bonds formed between bricks. These bonds are created by arranging bricks in a specific pattern and connecting them with mortar, which fills the spaces and grooves between bricks to form a cohesive structure. Choosing the right bond style is crucial in masonry, as it influences the strength, stability, and appearance of the wall. The most commonly used materials for bonding bricks include cement mortar, lime mortar, and, in some cases, mud mortar.
In this article, we’ll discuss the primary types of bonds used in brick masonry, their structural roles, and additional, less common bond types used in decorative or specialized applications.
Common Types of Bonds in Brick Masonry Wall Construction
The four primary bonds commonly used in brick masonry construction are:
- Stretcher Bond
- Header Bond
- English Bond
- Flemish Bond
Each bond type has unique characteristics, applications, and limitations, which we’ll explore in detail below.
Detailed Explanation of Common Bonds
1. Stretcher Bond
In stretcher bonds, bricks are laid with their longer, narrow side (stretcher) facing outward. This simple pattern, also known as a running bond, involves each brick overlapping halfway over the one below it in successive layers.
- Use: Stretcher bonds are primarily used in half-brick thick walls, such as partition walls.
- Limitations: This bond lacks the strength required for full-width load-bearing walls and generally requires additional structural support.
- Applications: Commonly used in steel or reinforced concrete-framed buildings as an outer facing and in cavity walls, as well as for boundary and garden walls.
2. Header Bond
Header bonds are formed by placing each brick with its shorter, square end (header) facing out. This type of bond is also known as a heading bond.
- Use: Suitable for full-brick-thick walls, usually around 18 cm in thickness.
- Key Feature: To achieve consistent overlap, three-quarter bricks are used at intervals.
- Applications: Often used in walls requiring greater thickness and structural strength than those built with stretcher bonds, such as walls in full brick thickness.
3. English Bond
English bond is a robust and widely used bond that alternates courses of stretchers and headers. Headers are centered on the stretchers below, with each row aligned vertically.
- Structural Advantage: The alternating courses create excellent structural stability, and the arrangement helps distribute load across the wall.
- Special Technique: Quoin closers, or bricks cut lengthwise, are placed at corners to enhance stability.
- Applications: English bonds are highly suitable for load-bearing walls, where strength and durability are key considerations.
4. Flemish Bond
Flemish bond, also known as Dutch bond, alternates headers and stretchers within each course, resulting in a visually appealing pattern. It requires skilled workmanship to ensure accurate alignment of vertical mortar joints.
- Aesthetic Advantage: The alternating header-stretcher pattern gives Flemish bond a decorative look, making it a popular choice when appearance is prioritized.
- Sub-types:
- Single Flemish Bond: Combines Flemish on the front with English bond at the back to blend strength and aesthetics.
- Double Flemish Bond: Alternates headers and stretchers on both faces, giving a uniform look but with slightly reduced structural strength.
- Limitations: This bond is weaker than the English bond in terms of load-bearing capability and requires skilled labor.
- Applications: Ideal for visually appealing walls that may be plastered later, as well as decorative wall applications.
Other Types of Bonds in Brick Masonry
Apart from the primary bonds, several other bond types are used for specialized purposes, such as decorative patterns or unique structural needs:
- Facing Bond: Combines bricks of different colors or textures, used mainly for facade enhancement.
- Dutch Bond: A variation of the English bond, often used for its aesthetic appeal.
- English Cross Bond: An adaptation of the English bond that provides enhanced horizontal alignment for added strength.
- Brick on Edge Bond: In this bond, bricks are laid vertically, providing a distinct pattern suitable for decorative purposes.
- Raking Bond: Bricks are laid diagonally to add strength and aesthetic appeal, commonly used in curved or angled walls.
- Zigzag Bond: Features a diagonal pattern, creating a unique look that also reinforces wall strength.
- Garden Wall Bond: An arrangement of stretcher and header courses designed for garden walls, where aesthetics often play a significant role.
Conclusion
Choosing the right bond type in brick masonry is essential for achieving both the desired structural stability and aesthetic effect. The primary bonds – stretcher, header, English, and Flemish – offer a range of options for different wall types and functions. While the English bond is known for its strength, the Flemish bond provides a visually appealing pattern but requires higher skill and labor. Other bonds such as the facing, Dutch, and raking bonds offer unique designs for specialized applications.