Method of Laying Brickwork in Masonry Construction - lceted

METHOD OF LAYING BRICKS

Tests to find the quality of bricks have been studied in the previous article. Good bricks should not disintegrate when placed in water. This is very important as when these bricks are used with cement mortar, we should thoroughly soak them before laying. Only when fat lime or clay mortar is used or when one is forced to use bricks that are not well burnt, this soaking rule has to be relaxed. The time of soaking can be found from a field test. In all cases, bricks should not be handled in baskets or in any other mode which will destroy the sharpness of their edges.

 

How do you build a masonry wall? | Procedure of Brickwork in Masonry Construction

Brick Laying Operation

The operation of bricklaying in ordinary general work is as follows. A layer of mortar is spread to cover the full width of the wall for a suitable length of the lower course. The end brick is then laid on it. Each brick is then properly bedded usually with frog up. (Bricks with 10 mm deep frog are to be laid with frogs up and bricks with 20 mm deep frog are usually laid with frog down to save the quantity of mortar.)

 

For this purpose, the inside faces of each brick are buttered with mortar before the next brick is laid and pressed against it by tapping it with the handle of the trowel or wooden mallet. On completion of a course, the vertical joints are fully filled with mortar from the top. Finally, we press the side bulging mortar in firmly to be level with the face of the wall if it is to be left unplastered.

 

In the common practice adopted by many masons, a row of bricks is first placed on a thin layer of bed mortar leaving the cross joints empty. Then a heap of mortar is thrown over the top of the bricks and the cross joints are filled with mortar placed on the top with a trowel or straight edge while adding a copious amount of mortar. Strictly this is not a good practice. (However, when using cement mortar of high strength, the loss of strength due to violation of these rules may be only marginal.)

 

The walls are raised truly plumb. All courses are laid truly horizontal and all vertical joints truly vertical. Vertical joints in alternate courses should come directly, one over the other. The thickness of the brick course is to be kept uniform. For this purpose, a wooden straight edge with graduation giving a thickness of each brick course including joint can be used for guidance.

 

For a thick wall, the above operation is repeated along with both faces of the wall and the interior filling bricks for the thick wall are laid in a similar manner. The open joints inside are filled with mortar as each course is completed.

 

This operation of filling open joints is termed flushing-up. It is wrongly omitted for several courses on some badly-executed jobs and only done afterwards (not after every course) in an inefficient manner. It is not a good practice and should be avoided as it is essential that every course should be flushed up to the level if good work is required.

 

Grouting

When brickwork is set with a fine joint, it is usual to fill the interior joints with a thin liquid mortar. This process is called grouting.

 

Larrying

In heavy engineering works or buildings, where the walls are very thick, the facing bricks are laid in the usual manner. For laying the inner bricks, mortar is shovelled into the interior of the course, spread out and water is added at the same time to thin out the mortar.

 

The filling bricks are then squeezed into position. The mortar rising and filling the vertical joints completely and forms an exceedingly strong and solid wall. This is known as larrying.

 

Building Rat Trap Bond

For a rat trap bond work (as in the construction of cavity walls), if the mortar is placed carelessly on the brick, some of it will fall into the cavities and will be wasted.

 

To avoid this, a piece of wood (about 1 metre long and 75 x 20 mm in section, as used for cavity walls) can be held in the hole over the middle of the wall to cover the cavities while applying the mortar.

 

What are the points to be considered while constructing brick masonry?

Points to be Observed

(i) At the end of the day's work, the top of the brickwork shall be thoroughly cleaned of all mortar and the frogs, if laid up, are kept exposed to their full depth so as to provide proper keying for the next course. The face of the brickwork shall also be cleaned of all mortar droppings, etc.

 

(ii) When circumstances render it necessary to carry on a portion of a building in uneven courses, the work shall be built back (according to the bond used on the work) at an angle not steeper than 45 degrees so as to ensure a uniform and effective bonding. It should not be left toothed.

 

(iii) If facework is to be left unplastered, every joint should be neatly struck at the close of the day's work and before the mortar has completely set to give a good appearance. Otherwise, for faces to be plastered, finishing of the face joints should be carried out as discussed in below  (This is very important.)

 

(iv) The walls should be uniformly raised all around not leaving any part one metre (three feet) lower than the other. A day's work should not be more than 1.5 m high.

 

(v) All iron fixtures such as holdfasts, pins, etc., to be built in the wall should be embedded in cement mortar or cement concrete in their correct positions preferably during the progress of the work itself or arrangements should be made to fix it without breaking the wall.

 

How to prepare the brick surface for plastering?

Preparation of Brick Surface Meant for Plastering

When the facework is to be later plastered or the joints alone are to be pointed, the joints must be raked while the wall is being built. It should be raked to a minimum depth of 12 mm by a raking tool during the progress of the work itself, when the mortar is still green.

 

If this raking is not carried out during the erection of the wall, the plaster to be added later may detach or fall off due to lack of grip, especially from smooth machine moulded bricks. If plastering or pointing is not envisaged, the joints must be struck flush and finished at the time of laying itself, as already stated.

What Is the Correct Ratio of Sand to Cement for Masonry?

 

How do you build a half brick wall?

How do you build a 4.5” brick wall?

Half-brick walls tend to crack unless care is taken in its construction. Brickwork in half-brick masonry is to be carried out with stretchers in 1 : 5 mortar.

 

In special cases, if it is considered necessary to reinforce the same (as in long lengths of walls) with two 6 mm MS bars provided at every third or fourth course in 20 mm rich cement mortar 1 : 3. Half the mortar joint (10 mm) is first laid and the other half (10 mm) is laid after the reinforcement is placed so that it is fully embedded in the mortar. (Any contact of the reinforcement with the brick will hasten corrosion of the steel and damage of the wall.)

 

These walls are generally plastered with cement plastering 1 : 5 with a thickness of 12 mm. This plastering also adds to the strength. If these walls are planned to be stopped at door height (as usually done in the tiled roofs with ceilings), the walls should not be stopped exactly at top of the door level and abruptly left at that level.

 

One layer of bricks should be laid over the door frame and throughout the length of the wall and then only the partition wall should be finished. A top layer of steel in cement mortar is also advisable.

MUST-READ: Types of Bonds Used In Brick Masonry Wall Construction And Their Uses

How to Protect and Curing for Brick Walls?

Brickwork should be protected from rain by suitable covering when the mortar is green. Ideally curing of brickwork, especially in cement mortar, is done (as in concrete work) by thoroughly saturating it with water after setting of mortar (preferably after covering it with straw, hessian, gunny bags, etc.) for fourteen days.

For important works, further curing by wetting once a day is to be continued for another seven days. However, in actual practice, the curing is carried out by keeping the work moist for a minimum period of seven days only. Brickwork in lime mortar also requires gradual drying out but does not require as careful curing as brickwork in cement mortar. (Lime mortar acquires strength by carbonation.)

 

How to Do Scaffolding For Brickwork?

Ideally, double scaffolding with two sets of verticals is to be used for exposed and important works. For ordinary works, single scaffolding with one end of horizontals resting on the wall being built is permitted.

Where the scaffolding pole rests on the wall, only one header brick shall be left out so that the bond of the wall can easily be made complete and perfect after the scaffolding is removed. Such holes shall not be allowed in places such as in pillars or columns (less than one metre in width) carrying heavy loads.

 

Where 4.5 Inch Wall Used in Building Construction?

Half brick wall or 4.5 inches (120mm) thick brick wall used for internal wall partition

 

Can we use a 4.5-inch wall as a load-bearing?

No

 

How many bricks equal a cubic foot?

14 nos

 

How many bricks are in a lorry load?

3000nos