Detailed Specifications of Brickwork
First Class Brick Work First class bricks and cement mortar are applied for first-class brick work. It is mostly suitable for load bearing walls. It is made of rich mortar with a ratio of 1:3 to 1:6 between cement and sand. First class bricks are recognized with their uniform color and a ringing sound created by striking the bricks with each other . The edges and surfaces of the bricks are smooth & the size is uniform. These bricks are not chipped and do not contain any cracks. First-class bricks do not consume water in excess of 1/6 of their weight. When the bricks remain dry, there is no salt deposit. First-class bricks contain at least 105.kg of crushing strength per square. cm
Specifications of First class brickwork • • • • •
All the used bricks should be first-class. Check first-class brick characteristics. Prior to use, bricks should be immersed in a tank. Soaking should remain in progress unless the air bubbles are stopped. Soaking should be done for a period of 12 hour before use.
Mortar specifications for first class brickwork • • • • • • • • • • • • • •
Material of mortar should have uniform specifications. For mortar, fresh ordinary Portland cement with uniform specifications should be used. Sand should be sharp and does not contain any organic and foreign particles. The sand should be coarse or medium to make the mortar dense. Local fine sand can be utilized for weak mortar. Cement sand ratio of mortar should be 1:3 to 1:6 as indicated. Mortar materials should be weighed with the measuring box in order to achieve the correct proportion. To retain a consistent color, the materials of mortar should be mixed dry initially. The platform should be cleansed properly for mixing mortar. Mixing should be completed for minimum three times. Water should then be slowly added to make it workable. Mix the mortar freshly. There should be no use of old mortar. For one hour of work, mortar should be mixed with water to allow morter to be used prior to setting.
Lime Surkhi mortar • • • •
If the lime surkhi mortar is indicated, it should be mixed in a ratio of 1:2 to 1:3, as defined, by grindi ng in a mortar mill for minimum three hours on the same day. Lime is supposed to be fresh and filtered. It is recommended to utilize fresh mixed mortar. Hand mixing is allowed for small works, just as for cement sand mortar.
Placing of first class brickwork • • • • • • • • • • • • • • • •
Unless otherwise stated, bricks should be arranged in English bond. Each course of brick should be arranged horizontally. There should be a perfect plumb wall. Consecutive brick layer vertical joints should not be put on each other. Alternate brick layer vertical joints will come directly over each other. Clean cut bricks should be used for closers. Closers should be positioned at the end but not at the other side of the walls. For face work, the brick with perfect shape should be applied. The mortar joint should not surpass the thickness of 6 mm or 0.5 inches. Mortar should be used to fill the joints entirely. Bricks should be placed upwards with frogs excluding in the top brick layer. Frog should be placed downward at the top of the brickwork course. Brickwork should be accomplished at a height of 1 meter or 3 feet. The stepping should be performed at an angle of 45 degrees if one part of the wall is required to be delayed. If projections are required in one course, it should not be in excess of 1/4th of the brick. All joints are raked and faces of wall are cleansed after completion of each day’s work.
Curing of First class brickwork • •
For minimum 10 days, brickwork should be retained wet. Top of the walls should be drenched with adequate water at the end of the days work by creating small weak mortar edging to include minimum 2.5 cm or 1 inch deep water.
Other requirements for first class brickwork • • •
Brickwork should be covered during construction to keep it safe from the harmful effect of heat, rain, frost, etc. In order to facilitate the construction of brickwork, there should be appropriate scaffolding. Scaffolding should be adequately strong to be able to withstand all the expected loads.
Measurement of First class brickwork • • • • • •
The measuring unit for brickwork should be in cubic meter or cubic feet. Different types of brickwork containing different mortar should be taken under individual item. Thickness of wall is considered as multiple of half brick. As for instance half brick wall thickness is considered as 10 cm or 4.5 inch. Full brick wall thickness is considered as 9 inches or 20 cm and so on. Rate is taken for the complete work along with scaffolding and all tools and plants utilized.