AAC Block is the most commonly used construction material for Blockwork. It is easily available in market with various thickness like 100mm,150mm and 200 mm.
Some check points to be considered while doing blockwork
Pre Masonary Checks
1) Clean the entire floor before starting the line-out of masonry and then apply cement slurry before layout.
2) RCC surface to be hacked properly / bonding agent need to be applied if Sand Cement Mortar Used.
3) Green mortar dash to be applied to RCC surface.
4) Do Lay out with higher grade or DPC course in RCC as specified.
5) AAC blocks to be wetted by sprinkling as specified
6) Tray / bund to make available at masonry location.
7) Required size of pharmas to make available for batching of sand if required.
8) Required size of cans to measure water for control of water cement ratio.
9) Ensure that all required type of tools available with mason.
10) Do Sieving of sand through 4.75mm sieve for Sand cement Mortar used.
11) Checking should be done as per Architectural drawings
During Masonary checks
1) Dimensions and diagonals of room checking after first layer done.
2) Vertical mulian reinforcement as per drawing and check the position for the same.
3) Powder water ratio shall be maintained in 25 – 30 % as specified by Manufacturer.
4) Block work should be in proper alignment and plumb. 5 / 5mm
5) Joint thickness (horizontal / vertical) to be maintained properly. (3-5mm)
6) Filling of joints is mandatory as bonding is directly depends on the surface.
7) The height of block masonry constructed in a day not more than 1.2m max.
8) First layer of Jointing mortar shall apply on DPC course/ Concrete Bund properly and then place blocks.
9) RCC band (patli) to be placed in masonry at 1 meter. Reinforcement to be checked and dimensioned.
10) Joint between R.C.C. beam frame and brick masonry shall keep at 20 mm.
11) Lintel anchorage and bearing adequate as per General design guidelines
12) Anchoring of holdfast as specified
13) Metal packing to be done at junction of RCC & masonry – Ascogrout shall place in between RCC and block jointing.
14) RCC band (patli) shall place in masonry at 1 meter only after full block layer completion and arrange thickness of bond beam accordingly so that there should not be any cut piece used in the last layer of the block.
Post Masonary checks
1) Check the jointing of block is done properly and gaps also filled by jointing mortar.
2) Concrete bund, Bond Beam & Vertical Mulian shall be cured properly for minimum 10 days.
2) Gaps shall be filled with Jointing mortar to ensure proper bonding.
4) Plumb of Masonary shall be checked and maintained properly.
Most important component of Blockwork
1) DPC – Damp proof course is one of the most important elements of a blockwork. The DPC protects the property against moisture rising from the ground. During the construction of DPC on plinth the surface to be neat and clean. If 100 mm blockwork is there 100 mm thickness of DPC required. Height of DPC generally varies between 150 mm to 200mm. The height to be adjusted in such way that last layer of block shall be full piece (No cut piece).
If steel provided in design then it should place in middle of DPC height and should be drilled in RCC wall.
2) Bond Beam /Tie Beam/Patli Beam – To avoid the buckling a tie beam / patli is provided in wall, which reduces the free standing height of wall. When we build a structure in reality like, home, hospitals, commercial spaces etc. we have constraint of space and to reduce the cost, smaller thicknesses of walls are designed. When we cant increase the thickness of wall, only option left is to reduce the height of wall by introducing the Tie beam / Patli into the wall.
In Tie beam / Patli reinforcement , steel bar should be taken either into column, beam or slab so that they can hold the wall and reduce its free standing height.
Tie beam / patli is useless if its not anchored in the structure.
3) Mullion -A mullion is a vertical element that often constructed at Door opening ,Window opening and if wall is longer, then at every 3 meter distance mulions shall be casted as per drawing.
Mullions are tall slender masonry columns which span between the massive masonry construction of the main wall construction. They supports panes of glass, which are subjected to strong gusts of wind. General thickness of mulions is preferred 150 mm for 100 mm blockwork wall, and 200 mm for 150 and 200 mm thickness wall. As per design steel vertical bars and stirrups to be provided maintaining the spacing. Purpose of mulion only be fulfilled when the vertical bars inserted into top slab.
4) Lintels -Lintels are structural components installed over an opening in a wall, like a window or a doorway, to support the loads above the gap and prevent the structure from collapsing. When the height of door is 2.4 m then lintel shall be 200 mm for 100mm thick block work and 250mm when 150mm and 200 mm thick block work.
