Brick Masonry

BRICK MASONRY

Brick masonry is built with bricks bonded together with mortar. For all permanent buildings lime or cement mortars are used. But for temporary sheds mud mortar may be used. Brick masonry strength depends on the type of bond and materials used for construction. They play an important role in providing strength, stability, and durability to the brick masonry.

TYPES OF BRICK MASONRY

The arrangement of bricks in brick wall construction is called brick bonds. Types of bonds in brick masonry wall construction are classified based on laying and bonding style of bricks in walls. The bond in brick masonry is developed by the mortar filling between layers of bricks and in grooves when bricks are laid adjacent to each other and in layers in walls. The various types of bonds generally used in brick masonry are:

❖ Stretcher Bond: A stretcher is the longer narrow face of the brick. Stretcher bond is also called as running bond. This type of bond is created when bricks are laid with only their stretchers showing, overlapping midway with the courses of bricks below and above. Stretcher bond in the brick is the simplest repeating pattern. But the limitation of stretcher bond is that it cannot make effective bonding with adjacent bricks in full width thick brick walls. They are suitably used only for one-half brick thick walls such as for the construction half brick thick partition wall. Walls constructed with stretcher bonds are not stable enough to stand alone in case of longer span and height. Stretcher bonds are commonly used in the steel or reinforced concrete framed structures as the outer facing. These are also used as the outer facing of cavity walls. Other common applications of such walls are the boundary walls, gardens etc.

❖ Header Bond: A header is the shorter square face of the brick. Header bond is also known as heading bond. In header bond brick masonry all the bricks are arranged in the header courses. This type of bond is useful for the construction of full brick thick walls. In header bonds, the overlap is kept equal to half width of the brick. To achieve this, three quarter brick bats are used in alternate courses as quoins.

❖ English Bond: English bond in brick masonry has alternate courses consisting of headers and stretchers. Headers are laid centered on the stretchers in course below and each alternate row is vertically aligned. This is considered to be the strongest bond. Hence it is commonly used bond for the walls of all thicknesses. To break the continuity of vertical joints, quoin closer is used in the beginning and end of a wall after first header. A quoin close is a brick cut lengthwise into two halves and used at corners in brick walls.

❖ Flemish Bond: In this type of bond each course comprises of alternate header and stretcher. Alternate courses start with stretcher and followed by header. Flemish bond is also known as Dutch bond. To break the vertical joints queen closers are required, if a course starts with header. Every header is centrally supported on the stretcher below it. The thickness of Flemish bond is minimum one full brick. The disadvantage of using Flemish bond is that construction of Flemish bond is difficult and requires greater skill to lay it properly as all vertical mortar joints need to be aligned vertically for best effects. In walls having their thickness equal to odd number of half bricks, bats are used to achieve the bond. Flemish bonds have better appearance but are weaker than English bonds for load bearing wall construction. Thus, if the pointing has to be done for brick masonry walls, then Flemish bond may be used for better aesthetic view. If the walls have to be plastered, then it is better to use English bond. Flemish bonds may be further classified as:

Single Flemish Bond: It is a combination of English bond and Flemish bond. In this type of construction, the front exposed surface of wall consists of Flemish bond and the back surface of the wall consists of English bond in each course. Minimum thickness required for single Flemish bond is one and a half brick thickness. The main purpose of using single Flemish bond is to provide greater aesthetic appearance on the front surface with required strength in the brickwork with English bond.

Double Flemish Bond: Double Flemish bond has the same appearance both in the front and back elevations, i.e. each course consists of alternate header and stretcher. This type of bonding is comparatively weaker than English bond.

❖ Garden wall bond: The arrangement of bricks in the English Garden Wall is similar to that of the English bond except that the heading courses are only inserted at every course whereas stretchers are used in bodi consequent courses. In short, the arrangement consists of one course of headers and three courses of stretchers. The queen closer is placed next to the queen header of the heading course for giving the necessary lap. The Flemish garden wall bond has Stretcher, Header & Stretcher Model. It is also known as Sussex Bond. It is also known as balanced bonding. In the Flemish garden wall bond, it is two types of variation of Flemish bond one is 3 stretchers in 1 header ratio other is 2 stretchers in 1 header ratio.

❖ Raking Bond: In this bond type, the bonding bricks are laid at any angle except zero or ninety degrees. This type of arrangement helps to increase the longitudinal stability of thick walls' built-in English bonds. In this pattern of bonding, the space between the all external stretchers of a wall is filled using bricks inclined to the face of the wall. Raking bond is introduced at certain intervals along with the height of any wall. It is of two types:

Diagonal Bond: It is best suited for walls of two to four brick thicknesses. A diagonal bond is normally introduced at every fifth or seven-course along with the height of the wall. Bricks in this type of bond are placed end to end in such a way that extreme corners of the sequence remain in contact with stretchers.

Herringbone bond: This type of bond is suited for very thick walls usually not less than four bricks thick. In this pattern of brickwork, bricks are laid in course inclined at 45° in 2 directions from the center. This type of bond is also commonly used for brick paving.

❖ Zigzag bond: Zig Zag Bond is very similar to herring-bone bond. The only difference is that in this case the bricks are laid in a zig-zag pattern. It is mostly adopted in brick-paved flooring.

❖ Stack bond: In a stack bond, all the bricks are plainly loaded on top of each other and held with mortar where all bonds are perfectly aligned. Because of its weak masonry structure and less strength, Stack bonds are perfect for decorative purposes. This bond is a non-structural bond, hence not suitable for walls which require transferring loads.

BENEFITS AND LIMITATIONS OF BRICK MASONRY OVER STONE MASONRY

Benefits:

❖ Bricks are light in weight and hence handling them is easy.

❖ Bricks are easily available around cities and their transportation cost is less because their weight is less. Stones are to be brought from quarries which are located only at few places.

❖ Since shape and size of bricks are uniform, it does not need skilled labour for the construction.

❖ It is possible to use all types of mortar in brick masonry. For temporary buildings even mud mortar can be used.

❖ In brick masonry mortar joints are thin and hence construction cost is reduced considerably.

❖ Brick masonry has better fire and weather resistance compared to stone no s masonry.

❖ Thinner walls can be constructed with bricks but it is not so with stones.

❖ It is easy to form openings for doors and windows.

❖ Dead load of brick masonry is less.

Limitations:

❖ ❖Strength of brick masonry is less than that of stone masonry.

❖ Brick masonry needs plastering and plastered surface needs colour washing. Stone masonry doesn't need them and hence maintenance cost is more in brick masonry.

❖ Brick masonry absorbs water and there is possibility of dampness. There is no such problem in stone masonry.

❖ Stone masonry gives massive appearance and hence for monumental buildings stone masonry is preferred over brick masonry.

❖ More architectural effects can be given in stone masonry compared to that in brick masonry.

❖ Durability of brick masonry is less when compared to stone masonry.