AAC BLOCK MASONRY

AAC BLOCK MASONRY1Prerequisite

Before starting any block work, prepare masonry layout on a typical floor plan. Thickness of each wall is marked on plan in different colours.Marking (Chhapkam) must be done on every floor and before starting of block work, concerned site engineer must check the opening, room dimensions, position of door frames and windows as per the architectural working drawings.Pre-wetting of block should be done before 2 hrs, and it should be surface dry at the time of using.

2Masonry3Marking (Chhapkam)

PPC cement with a proportion of 1:6 is to be used for 1st and last layer of masonry having joint thickness of 10-12mm.

4Application of Chemical MortarMix proportion :- Water : Chemical = 1:3 or As per Material specification.First Course (Nondh): The first course of concrete block masonry shall be laid with great care, making sure that it is properly aligned, levelled and plumbed, as this may assist the mason in laying succeeding courses to obtain a straight and truly vertical wall.

5Every layer of chemical mortar should applied with notched trowel

Thickness of layer should be min. 5mm.6Line, level and plumb should be checked for every layer.

7Bends, stubs and studs should be provided as per approved drawing

8Joint should be staggered and to be filled up with mortar

9Checklist for AAC block Sr. No.Checks DescriptionYesNoNot Applicable1.Surface cleaning, removal of nails, binding wire from RCC member2.Check quality of blocks and dimensions (Approved source)3.Check type of masonry and the nature of bond required4.Reduced level to be marked at each column5.The level of RCC band marked on the column with due consideration of layer thickness6.Marking of wall layout7.Wetting of surface of block. Mortar ratio 8.Check after 1st layer Dimension, right angles, plumb, offset etc.9.For successive layer checka.Plumb, levelb.Consistency of mortarc.Raking of jointsd.Level of RCC stiffener10.Provision of openings, doors, windows10Plastering11Before plasteringPlaster should only be started after completion of block masonry and electrical works.Plaster to be started only after complete curing of electrical casing (Zari), Repair works if any should be done.Check the door and window frames alignment, level and plumb before starting the plaster.Clean the RCC surface with water and remove tapes, nails, slurry leakage, shuttering oil and also repair honeycombing if any.

12Chicken mesh should be provided at electrical casing and junction of RCC and Masonry before 24hr of plastering.All hacking/tancha work (roughing the surface) should be finished on R.C.C work.

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Plastering1:4 CM should be used..Once the making of tanchas (roughing the surface) are done,12 to 15 mm thick plastering block/level pads (Thaiyas) should be prepared on masonry work for referencing purpose.With the respect to plastering block/level pads (Thaiyas), whole plastering activity should be carried out.

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Preparation of surface should be carried out before plastering with chemical mortar

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First coat of plaster should be applied with mortar of high water content. Then subsequent coat should be applied with mortar of low water content.At last it should be finished with the help of float and trowel. No uneven surface should be observed.Write date of plastering on the plastered surface for 7 days curing.

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Checklist for plasteringSr. No.Checks DescriptionYesNoNot Applicable1Surface preparationa. Hacking of RCC surfaceb. Provision of chicken mesh at RCC and Masonry junctionc. Cleaning of the surface where mortar is to be mixedd. Wetting of base surfacee. Check thickness of level pads2Check that proper scaffolding is provided3Check type of plaster4Check No. of coats and thickness required5Check mix proportion 6Check consistency of mortar7Check dimension, right angles, plumb, door / window opening8Check curing for 7 days17

Thank you18