Specifications of First class brickwork
- All of the bricks used should be of first class.
- See the characteristics of first class bricks .
- Soaking of bricks should be done by submerging in a tank before use.
- Soaking should be continue until the air bubbles are ceased.
- Soaking should be for a period of 12 hour before use.
Mortar specifications for first class brickwork
- Material of mortar should be of standard specifications.
- For mortar, cement should be fresh ordinary Portland cement of standard specifications.
- Sand should be sharp and free from organic and foreign particles.
- If we want to make rich mortar, sand should be coarse or medium.
- For weak mortar, local fine sand may be used.
- Cement sand ratio of mortar should be 1:3 to 1:6 as specified.
- To get the required proportion, materials of mortar should be measured with the measuring box.
- Materials of mortar should be first mixed dry to have a uniform color.
- The platform should be clean for mortar mixing.
- Mixing should be done at least three times.
- Then water should be added gradually for workable consistency.
- Mortar should be freshly mixed.
- Old mortar should not be used.
- Mortar should be mixed with water for one hour work so that mortar may be used before setting.
Lime Surkhi mortar
- If specified lime surkhi mortar, should be mixed in 1:2 to 1:3 ratio as specified, by grinding in mortar mill for at least three hours to use on the same day.
- Lime should be fresh and should be screened.
- Fresh mixed mortar should be used.
- For small work, hand mixing may be allowed just as in the case of cement sand mortar.
Laying of first class brickwork
- Bricks should be laid in English bond unless otherwise specified.
- Every course of brick should be horizontal.
- Wall should be truly in plumb.
- Vertical joints of consecutive brick layer should not come on each other.
- Vertical joints of alternate brick layer should come directly over one another.
- Closers should be of clean cut bricks.
- Closers should be placed at the end of the walls but not at the other edge.
- Best shaped brick should be used for face work.
- Mortar joints should not exceed 6 mm or 0.5 inch in thickness.
- Joints should be fully filled with mortar.
- Bricks should be laid with frogs upwards except in the top brick layer.
- In the top course of brickwork, frog should be laid downward.
- Brickwork should be done for 1 meter or 3 feet height at a time.
- When one part of the wall has to be delayed then stepping should be done at an angle of 45 degree.
- Projections where made should not be more than 1/4th of the brick in one course.
- All joints should be raked and faces of wall should be cleaned at the end of every day’s work.
Curing of First class brickwork
- Brickwork should be kept wet for the period of at least 10 days.
- Top of the walls should be flooded with water at the end of the days work by making small weak mortar edging to contain at least 2.5 cm or 1 inch deep water.
Other considerations for first class brickwork
- Brickwork should be protected from the effect of sun, rain, frost etc., during the construction.
- Suitable Scaffolding should be provided to facilitate the construction of brickwork.
- Scaffolding should be strong enough to withstand all the expected loads to come upon them.
Measurement of First class brickwork
- Brickwork should be measured in cubic meter or cubic feet.
- Different kinds of brickwork with different mortar should be taken under separate item.
- Thickness of wall should be taken as multiple of half brick.
- For example half brick wall thickness is taken as 10 cm or 4.5 inch.
- Full brick wall thickness is taken as 9 inches or 20 cm and so on.
- Rate should be for the complete work including scaffolding and all tools and plants used.
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