Building_Construction (1)

Basic Concept about Building Construction Prepared By S M NazmulHaque

Construction Stages • For any type of Project the Construction Stages are • Conception of Scheme • Site Investigation • Designs • Drawings & Estimating • Preparation of Specifications • Procurement of Materials • Supervision

Construction Stages for Building Project • For Building Project the Construction Stages are • Conception of Scheme • Take clear concept about the function of building, feasibility study etc. • Site Investigation • Concept about the neighborhood environment, land dimension, soil testing etc. • Designs • Architectural and Structural Designs • Drawings & Estimating • Detail Working Drawing and Estimation of BOQ • Preparation of Specifications • Detailed specification about each item of construction

Construction Stages for Building Project • Preparation of Time Schedule • Prepare time schedule to complete the project in time. • Procurement of Materials • Procurement of materials and supply materials to the site within scheduled time to continue the project without interruption. • Construction • Sub-Structure • Super-Structure

Construction Time Schedule(For a small construction) • Excavation 7 days • Cement concrete in Foundation 4 days • Masonry in Foundation 7 days • Masonry in Superstructure 28 days • Roofing 7 days • Plastering 14 days • Wood Work 7 days • Flooring 14 days • Fixing Service 14 days

Construction Time Schedule

Sequences of the Building Construction • Site Clearance • Demarcation of Site • Positioning of Central coordinate i.e. (0, 0, 0) as per grid plan • Surveying and layout • Sub Structure • Foundation work • Shallow Foundation • Deep Foundation • Under Ground Reservoir • Grade Beam

Sequences of the Building Construction • Super Structure • Short Column • Column and Beam • Slab • False Slab • Brick Work • Lintel • Duct and Grill • Electrical and Plumbing • Sanitary Work • Window and Door • Plaster • Final Finishing Work

Sequences of the Building Construction • Site Clearance : The very first step is site clearance which involves removal of grass and vegetation along with any other objections which might be there in the site location. • Demarcation of Site: The whole area on which construction is to be done is marked so as to identify the construction zone. In our project, a plot of 450*350 sq ft was chosen and the respective marking was done. • Positioning of Central coordinate and layout : The centre point was marked with the help of a thread and plumb bob as per the grid drawing. With respect to this center point, all the other points of columns were to be decided so its exact position is very critical.

Shallow Foundation Sub Structure • Foundation • Shallow foundation : A foundation whose depth below the surface is equal to or less than its least dimension. Most strip and pad footings fall into this category. • Strip foundation : Often termed a continuous footing this foundation has a length significantly greater than its width. It is generally used to support a series of columns or a wall. • Pad footing : Generally an individual foundation designed to carry a single column load although there are occasions when a pad foundation supports two or more columns. • Raft foundation : This is a generic term for all types of foundations that cover large areas. A raft foundation is also called a mat foundation and can vary from a fascine mattress supporting a farm road to a large reinforced concrete basement supporting a high rise block.

Excavation • Excavation : Excavation was carried out both manually as well as mechanically. Adequate precautions are taken to see that the excavation operations do not damage the adjoining structures. Excavation is carried out providing adequate side slopes and dressing of excavation bottom. The soil present beneath the surface was too clayey so it was dumped and was not used for back filling. • Plain Cement Concrete: After the process of excavation, lying of Brick Flat Soling or cement concrete that is CC is done. A layer of 3 inches was made in such a manner that it was not mixed with the soil. It provides a solid base for the foundation. • Placing of Reinforcement will discuss on later slide.

Brick Flat Soling • Material Requirements: • 1st Class solid Bricks, fine sand. • Construction Methods: • Compact the surface by Hand rammer and sprinkling water. • Level the surface. • Lay the Bricks flat in surface contact with each other with frog mark upwards. • Keep Break joints in the subsequent row of Bricks in English Bond pattern. Joints will not be in the same line. • Use broken Bricks, if any, at the edge of the area. Fill small gaps or joints between the Bricks with local fine sand. (FM = Minimum 0.50) Brush in until the joints are filled with sand. Do not use water for flushing in of sand to the gaps. • Inspection • Check the finish surface is leveled both longitudinally and transversely.

Blinding Concrete (Mat Foundation) Material Requirement • Cement: Ordinary Portland cement • Brick Aggregate: Brick into chips of size 25mm downgrade. • Coarse Sand: (F.M.2.5-3.0) • Local sand: (F.M.1.2-1.5) • Water: Potable normally municipal supply water. Construction Methods: • Thickness: • Provide 75mm without Brick Flat soling. Use Polythene sheet below. • Provide 50mm over Brick flat soling. Use polythene below blinding concrete. • Provide 75mm over Brick flat soling in Ground floor car park area. Manufacture of Blinding Concrete: • Proportioning • Mix Cement, sand & brick khoa in the ratio of 1:3:6 by volume in Boxes or cans equivalent to volume of 1sack of cement.

Blinding Concrete Measurement of Material • Measure material volume in Boxes or cans equivalent to volume of 1 sack of cement. Mixing of Material • IC present at mixing place to monitor and control the ratio & quantity of material in the mix. • Machine mixing same as outlined in “RCC” instruction No. 09020500. • Alternative hand mixing allowed for blinding concrete as follows: • Mix the materials on a clean solid watertight masonry platform. • Spread the measured quantity of sand evenly on platform. • Dump and distribute the cement evenly on sand. • Mix sand & cement thoroughly until the mixture is of even color. • Spread the measured quantity of brick khoa in another place of platform. • Spread sand cement mix on Brick khoa. • Thoroughly mix the above at least 3 times- shoveling & turning over by twist from centre to side. Then again from side to centre and again from centre to side

Blinding Concrete • Add water gradually and turn the materials as above till the whole surface of each aggregate become coated with san cement mortar and the mix becomes plastic to give a uniform concrete. • Placing and Compaction • Clean the area from dust or of foreign materials. • Take level pillars of fresh concrete in the area at suitable intervals but not more than 2m c/c both ways. • Lay the concrete gently (not thrown) from one side. Use the concrete mix within 45 minutes after the water is added. • Use wooden rammer for compaction. • Roughen the surface for joining future work before the concrete bending. • Curing: • After 24 hours of laying of concrete moist the Blinding concrete surface by flooding with water or by covering with moist gunny bags at least for 7 days.

Deep Foundation • Deep foundation • A foundation whose depth below the surface is greater than its least dimension. Piles and piers fall into this category. • Pile foundation : Piles are used to transfer structural loads to either the foundation soil or the bedrock underlying the site. They are usually designed to work in groups, with the column loads they support transferred into them via a capping slab. • Pier foundation : This is a large column built up either from the bedrock or from a slab supported by piles. Its purpose is to support a large load, such as that from a bridge. A pier operates in the same manner as a pile but it is essentially a short squat column whereas a pile is relatively longer and more slender.

Pile Foundation • Why pile foundation is required • When the subsoil immediately below the foundation is not suitable to take up the loads from the structure, then pile foundation is required. • Why pile provided • To obtain the necessary bearing capacity on a bad soil. • Provided as a column support • Function of pile • Protect the foundation against slipping • Transfer the load (Soft Soil to Hard Strata) • Protect the foundation against scouring • Improving bearing capacity

Pile Foundation • Tripod • Horizontal rod • Chisel (φ = φ of pile - 2 in.) • Bucket • Funnel • Treme pipe • Casing • Wings machine • Mass rod (≈ 1 ton) • Boring pipe • Hosepipe • Suctions pipe • Pump engine • Steel bar • Cement concrete • Pulley • Mixing machine • Tape • Hook • Wire • Welding equipment • Leveling tube • Fera (generally 1/2 bag vol.) • Beller Required Instruments

Pile Foundation • Procedure of Pile Contraction • Identification of quality and sufficient stock of Materials • Identification of previously placed center of pile with reference to grid line • Centering the Chisel of Tripod Stand • Checking diameter of Pile and Chisel • Ensuring rebar’s free from rust, oil, etc. and Size, Length & Nos. of Steel bar • Conforming lap length according to Design • Ensuring proper welding and Clear Cover using chair • Diameter, Length of Casing pipe satisfactory • Identification of chisel diameter • Wash boring satisfactorily completed • Treme pipe length and diameter satisfactory • Ensuring safety, security and working environment

Pile Foundation • Pile Cap • Procedure of pile cap contraction • Excavating the earth fill where pile cap will be placed • Break down the pile up to pile cut off level • If desire fresh concrete is not found at required level, pile will break down until fresh concrete is grown up. That’s why, short column length will increase. • Leveling and compacting the earth level 3 inches below the pile cut off level • 3 or 4 inch. Cement Concrete will cast • Steel bar will placed according to Design • Checking of clear cover and shutter w. r to grid line • After casting the pile cap, short column will be cast up to grade beam

Grade Beam • Grade Beam • Procedure of grade beam casting • Excavating the earth where grade beam will placed • Compacting the bottom layer • 3” BFS will placed • Shuttering w.r.to grid line • Leveling the beam bottom • Checking of Steel bar and clear cover • Investigation of casting work and maintaining top level • Ensure perfect construction joint if needed

Column • Column • Procedure • 5 in. kicker is used to set up column in place • 1 tie will set up within 5 in. • Lapping must not exceeding 50% main bar in same place • 30D or 40D lapping is generally taken • Turn buckle is use for shuttering column • Key used for Bonding • Hessian sheet is use for curing • Concrete block is used for ensuring clear cover • Identification of proper vibration and dumping of concrete below 6 ft height • Function of Kicker: • Set up the column in place • Ensuring vertical alignment • Use as a support for shuttering of column

Slab • Slab Casting • Identification of required props and shutter (Wooden or Steel) • Identification of required plane sheet and rupban sheet • Leveling and checking of props and shutter • Checking out required steel bar and its placement • Checking Block and Chair used for maintaining clear cover • Identification of available materials and instruments for casting • Identification of slab level & investigating the vibration work • Check leveling which is done by Patta • Identification of electrical line, plumbing and sanitary duct, railing steel, drop wall steel • Proper curing should be maintain

Reinforcement • Reinforcing Bar Binding and placement • Material Requirements: • Tore steel-Cold twisted deformed bar conforming to BS 4461-1978 Procured from Manufactures like BSRM, Diamond Steel and Eastern Steel or other approved Trader or Product Brand. • Binding Wire: • Not above 24G galvanized iron wires. • Construction Methods: • Clean all loose scale, dirt, paint oil, grease, or other foreign substance from the reinforcement. • Cut the reinforcement as per sizes and as per lengths shown in the drawing. Stack the fabricated bars size wise & member wise. • Reject the bar which cracks during straightening. • Clean and Oil the form before placing reinforcement where applicable especially in case of slab. • Accurately place all reinforcing bars in exact position as per size and spacing shown on the drawings.

Reinforcement • Place sufficient Blocks, chairs & spacers so that bars do not sag between supports nor displaced during concreting or any other operation over works, Use spacer Bar, chair or Pre-Cast mortar blocks separate the Layer of bar. • Secure the Bar crossing each other by 24G Binding Wire so that they do not slip over each other at the time of fixing & concreting. • Keep Concrete cover as following to protect reinforcement from corrosion. • In foundation: 75mm • In column: 37mm • In Slab: 25mm • In Structure Adjacent to earth: 75mm • In roof beam: 37mm

Reinforcement • Terms used in Reinforcement • Bar-bending-schedule : Bar-bending-schedule is the schedule of reinforcement bars prepared in advance before cutting and bending of rebar's. This schedule contains all details of size, shape and dimension of rebar's to be cut. • Lap length: Lap length is the length overlap of bars tied to extend the reinforcement length. Lap length about 35 – 45 times the diameter of the bar is considered safe. Laps of neighboring bar lengths should be staggered and should not be provided at one level/line. At one cross section, a maximum of 50% bars should be lapped. In case, required lap length is not available at junction because of space and other constraints, bars can be joined with couplers or welded (with correct choice of method of welding).

Reinforcement • Anchorage Length : This is the additional length of steel of one structure required to be inserted in other at the junction. For example, main bars of beam in column at beam column junction, column bars in footing etc. The length requirement is similar to the lap length mentioned in previous question or as per the design instructions • Cover block : Cover blocks are placed to prevent the steel rods from touching the shuttering plates and thereby providing a minimum cover and fix the reinforcements as per the design drawings. Sometimes it is commonly seen that the cover gets misplaced during the concreting activity. To prevent this, tying of cover with steel bars using thin steel wires called binding wires (projected from cover surface and placed during making or casting of cover blocks) is recommended. Covers should be made of cement sand mortar (1:3). Ideally, cover should have strength similar to the surrounding concrete, with the least perimeter so that chances of water to penetrate through periphery will be minimized. Shape of the cover blocks could be cubical or cylindrical. However, cover indicates thickness of the cover block. Normally, cubical cover blocks are used. As a thumb rule, minimum cover of 2” in footings, 1.5” in columns and 1” for other structures may be ensured.

Concrete Material Required • Ordinary any Portland Cement. • Aggregate : Stone/Brick Chips of mean size 25mm downgrade. • Sylhet Sand : (F.M. 1.8 – 2.5) • Coarse Sand : (F.M. 1.2) Construction Method: Mixing: • Screen excessive dust from aggregate, max. Allowable dust 3% by volume. • Check the Formwork before commencing concreting. Clean the Formwork and wash, the Formwork with clean water thoroughly of all extraneous material before placing concrete. • Fix reference level mark with paint in reinforcement of column or with nails in formwork to control the thickness of concreting & level of the upper surface. • Measure the aggregates and sand as per proportion by can equivalent to a sack of cement.

Concrete • Dump the measured quantity or materials as per proportion specified in the drawing in the Drum of mixer machine and thoroughly mix with required quantity of water for a period of not less than 2 minutes after all material the water are in the drum, Control water quantity by measuring slump. Slump not to exceed 50 mm. PM must be at mixture machine point to control the quality of the mix and ensure slump. Placing • Depute QE at placing point of concrete, use the concrete within 45 minutes after the water is mixed. • Does not drop concrete freely from a height exceeding 2.00 M not deposit concrete in large quantities at any point exceeding 450 mm thick. • Make level or reference pillars with concrete before concreting operation proceeds. • Lay concrete from one end & then continuously proceed to the other end. Fresh concrete should not be deposited against concrete which is in position more than 45 minutes. The edges of old concrete are broken to give a firm bonding.

Concrete • Compacting: • Compact the concrete immediately after placing by internal vibrator till scum of mortar appears. Compact within 20 minutes the mixture is placed in position. • Do not vibrate much longer & stop vibrating as soon as laitance of mortar appears on the surface. Excessive vibration segregates the mix. • Do not apply vibrator directly against the reinforcement or against the concrete which has developed initial set. Apply vibration in the area of freshly deposited concrete. Do not allow vibrator to the concrete 2 hours after compaction. • Leveling & Curing: • Check and finish the top surface of concrete at every 37 from the reference painted or nail mark. • Keep scratch in the slab or provide keys in the column lift to put subsequent concrete in the proceeding days. • Keep the concrete surface after 24 hours continuously wet with water till the removal of Formwork with pounding of water or covering with wet Hessian cloth.

Concrete • Testing & Inspect: • During concreting, take slump of concrete for every 20 cum of concrete. Correct the mixture by adding cement and sand till the slump value is within 50mm. • Procedure for making & curing of Cubes and Cylinder. • Materials (concrete) for specimen should be taken from three on four random mixes. • The cylinder or cube should be properly cleaned & thinly oiled but no excess oil should be visible on the inner surface. • The nuts & boils should be lightly fixed with the base plate and no gaps should be there within the parts of cylinder on cubes. • It is necessary that the cylinder & cube should be on the level surface before making.

Form Work • Shuttering and Scaffolding : The term ‘Shuttering’ or ‘Formwork’ includes all forms, moulds, sheeting, shuttering planks, walrus, poles, posts, standards, leizers, V-Heads, struts, and structure, ties, prights, walling steel rods, bolts, wedges, and all other temporary supports to the concrete during the process of sheeting. • Form Work: Forms or moulds or shutters are the receptacles in which concrete is placed, so that it will have the desired shape or outline when hardened. Once the concrete develops adequate strength, the forms are removed. Forms are generally made of the materials like timber, plywood, steel, etc.

Form Work • Material Requirements: • Mango wood plank of various sizes. • Steel shutter. • MS Plain sheet. • Sheet metal lining. • Props. • Construction Methods: • Use all column form made of 16 SWG steel sheet with holes for fixing & tighten. Height should not exceed 2m. • Use wooden form for footing, beam and slab made of mango wood planks with minimum thickness of 25mm and include necessary battens, struts, runner & tics etc. Do not use warp wood for shutter. • Use steel shutter for Beam where directed, made of 16 SWG steel sheets with necessary holes & clamps and strong MS Angle Frame. • Wooden planks of size 125mm in width & 25mm in depth minimum for slab form. Clear gap between each plank should not exceed 150mm. • Use thin metal 32G sheet lining in between the joints of wooden form & properly nailing it to make form watertight.

Form Work • Form fixing: • Clean the steel Forms with steel scraper or steel brush to make it free of rust, encrustations of mortar or other foreign materials. • Apply oil to the Form either Mobil or thin tar to avoid sticking of the concrete with Form. Wipe out excess Form oil. • Tighten the column with nuts & bolts at any holes and with T-Bolts. • Check the Vertical Alignment both transverse and longitudinal & after proper verticality fix the steel shutter with turn bolt and tie bolt Then again check vertical alignment by adjusting turn bolts • Propping and Centering: • Use Bamboo post 3" dia as prop @ 600 mm C/C for slab. • In between bamboo props use steel post @ 1800 - 2100 mm C/C depending on size of room space. • Tight the props at both ends, no loose props should be used. • Use horizontal bracing at 12000mm level for height more than 3m. • In addition to turn bolt &. T -bolt fixing in the column shutter use bamboo/steel prop as strut in inclined. • Before concreting, check the props are intact and during casting keep 2 carpenter/shuttering men for constant watch on prop and take immediate remedial measure as soon as any of props get loosened.

Form Work • Immediately before concreting is commenced, the formwork is carefully examined to ensure the following: • Removal of all dirt, shavings, sawdust and other refuse by brushing and washing. • The tightness of joint between panels of sheathing and between these and any hardened core. • The correct location of tie bars bracing and spacers, and especially connections of bracing. • That all wedges are secured and firm in position. • That provision is made for traffic on formwork not to bear directly on reinforcement steel. • Verticality of the Structure • All the outer columns of the frame were checked for plumb by plumb-bob as the work proceeds to upper floors. Internal columns were checked by taking measurements from outer row of columns for their exact position. Jack were used to lift the supporting rods called props

Form Work • Removal of Form work: • Remove the Formwork as per time elapse after concreting. • Footing 1 days • Columns, walls, vertical members: 2 days. • Soffits of slabs and beams • (Up to 4.5m span) 14 days. • (Above 4.5m span) 21 days • Gradually and uniformly lower the props to avoid shock or vibration and damage to concrete. Operation should go from middle for slab bounded at all sides and for cantilever from free end. • Pull from wood all nails. Do not allow nail bending by hammering against the face of wooden form Board.

Common Reasons for Leak in Concrete Common Reasons for Leak of Quality in Concrete Work • Use of too much or too little water for mixing, or water carelessly added during mixing • Incomplete mixing of aggregate with cement • Improper grading of aggregates resulting in segregation or bleeding of concrete. • Inadequate compaction of concrete • Using concrete which has already begun to set. • Placing of concrete on a dry foundation without properly wetting it with water. • Use of dirty aggregate or water containing earthy matter, clay or lime. • Too much troweling of the concrete surface. • Leaving the finished concrete surface exposed to sun and wind during the first ten days after placing without protecting it and keeping it damp by proper methods of curing.

Brick Work and Plaster Work • Brick Work and Plaster Work • Instruments use for Brick Work and Plaster Work • Measuring steel tape • Leveling pipe • Sprit level • Tri square • Plum bob • Trowel • Wooden float • Mental float • Level gauge

Brick Wall Brick Wall Work Procedure • Before setup the layout floor should be keep clean • Identification of proper curing period of brick so that the water penetrates to its full thickness. Normally 6 to 8 hours of wetting is sufficient. • Before work, cured brick should be dry at least 1 hour • Chipping the area before brick place • Grouting by the water cement paste • Brick will place according to layout • Checking the verticality of brick work by plum bob • Vertical joints shouldn’t be continuous but staggered. • All bricks should be placed on their bed with frogs on top • Thread, plumb bob and spirit level should be used for alignment, verticality and horizontality of construction. • A maximum of one meter wall height should be constructed in a day. • The joint thickness shouldn’t exceed 1 cm. It should be thoroughly filled with the cement mortar 1:4 to 1:6 (Cement: Sand by volume) • Joints should be raked and properly finished with trowel or float, to provide good bond • Brickwork should be properly cured for at least 10 days

False Slab & Grill False Slab • Leveling by water level • Checking of reinforcement distribution • Position check for exhaust fan • Maintain proper distance with fan to light Grill • Thickness check by slide calipers • Measurement checks (width, length, diagonal etc.) • Vertical alignment check • Proper wielding for Grill

Plaster Work Plaster Work Procedure • Chipping ,Brush and scrap the cured surface to make it free from mortar oil, greasy spots and efflorescence and loose materials. • Wash the surface with water and kept surface moist (but no surface water) before commencing plaster Surface will be saturated surface dry. • CC will be as like as paste. (Ratio 1:4 to 1:6 depends on Surface) • Grouting the surface by the water cement paste • Set up the distance between two wall face • Vertical level check by gauge w. r. to beam face • Maintaining door’s wood in same level with plaster face

Curing • Following are the methods for curing different building parts:- • Walls – Water should be sprinkled from the top such that it covers the whole area of the wall and it should be remain wet. • Slab – Ponding should be done on the slab by constructing bunds of mortar • Beams and columns – The beams and columns can be maintained wet by tying gunny bags around the periphery and by maintaining it wet always. Roof Beam should be sprinkled from the top such that it covers the whole area of the beam and it should be remain wet.

Wood Work Quality control for Door’s wood Frame • Use wood which is free from sap. Knots. Cracks, large holes or any defects or diseases affecting appearance and strength. • Work on Dry timbers. • If the color of wood is light, it will bad • Dimension check • Sand paper the member to remove roughness & ensure plainness before assembling them. Joints must be well matched and tight. Properly glued and secured with hardwood screws.

Wood Work • Finish the surfaces smooth by sand papering and planer as to perfectly make the surface free from: • Disfiguring Effects • Stain • Dents Of Chisel • Uneven Planning • Uneven Sanding • Tool Marks • Scratches • Uneven Trimming and Gouges. • Paint the unexpected face of Frame in contact with masonry or concrete surface with 2 coats of tar paint before fixing. • Fix the frames truly vertical. Check the vertical alignment with spirit level and with plumb bob.

Wood Work • Shutter • Do not use wood as mentioned in above for shutters and that each plank must be straight without any wrap or bow. • Take planner machine with fine abrasive paper for smooth leveling of the shutter. No grain showed be detectable by touch with Hand and planning to continue till a smooth, highly level surface attained. • Before varnishing polishing properly clean surface free of dust, dirt adhesives and other foreign substances lightly rub down with abrasive paper each coat before applying the next No excess polish or polish mark be visible. Excess oil be removed to avoid sticky surface as it catch dust. Evenly spread the polish. • Use Lacquer polish (either yacht of elite or original China Lacquer) as final touch over 3 coats polish/Varnish. • Fix locks and other fastening only before fixing various sanitary and electrical fixtures. • However, for fabricated door shutters procured as for example for PARTEX Boards. • Properly store the door shutters in a dry well ventilated damp proof area. Do not store in area prove to alternated wet and driving. Prefabricated shutter in touch with water will swell become disfigured & warped.

Painting • Plastic Emulsion Paint: • Do not apply paint on the surface not cured for at least 14 days and which is not at least 45 days old. Use only in Interior. • Completely dry the surface. Do not use paint on wet or damp surface. • Brush down thoroughly with stiff Brush/Sand paper to remove loose surface contamination and particles. Scrape off hard and cement splashes. • Make defects with cement sand cure & completely dry the patch. • Apply water base sealer with brush/roller, coverage area 52sqm/4liter(1 Gallon). Add 20% water as thinner. Apply sealer uniformly so that surface is whitish.

Painting Putty preparation and application: • Preparation: • Chalk Powder (England) = 1 bag • Enamel paint = 1 Liter • Plastic Paint = 1 gallon • Water = as required as per surface condition to make paste • Applications • Days putty should be used on that day of preparation. After application of putty sand preparing to be continued till the visibility of plaster surface. • Paint to be applied after minimum 4 days of application of putty. • Percentage of water mixing with the paints for painting 1st coat. 20% water subsequent coats. 15% water interval 7 days minimum between successive coats. • Coverage Area: 32 sqm/4 liters can for spot less.

Painting Enamel Paint • Use enamel paint in steel structure Pipe rail or steel Gate etc. • Surface preparation • Use steel brush and emery paper no. 320 to rub the surface until rust/any scale/concrete mortar on the steel surface are removed. • Apply primer as follows; • For MS surface Red oxide/ Read Lead primer. • For G.I surface use Zinc Chromed primer. • 1st Coat: Thin with 5% max T-6 thinner and then apply after 2 days of primer application. 2nd & 3rd coat same as mentioned for plastic paint. Each coat thin with maximum 5% T-3.Thinner.

Painting Distemper • Use in interior wall & ceiling over plastered surface where recommended. • Surface preparation is same as plastic paint. • Add water to the Distemper. Mixing ratio of water to paint = 2:3. Thoroughly mix the paste with water to make unifom1 consistency. Do not mix with any other paint or powder. Do not keep thinned material for more than 1 how' for reuse. • Apply with Brush or roller. • Apply 2nd coat and 3rd coat in the above manner as for 1st coat but interval between successive coats be minimum 48 hours.

Painting • Outside Paint: • Use paint instructs color exterior cl\1ubion. Use 2 coats with primer or 3 coats without premier. • Use white cement mixed with Aica/Glue as primer and then cure for at least 7 days. • Thoroughly stir the paint and thin with 15% clean tap water. • Touch putty may be allowed if undulation is visible. • Apply 1st coat with Roller. • Completely dry the 1st coat.

Building_Construction (1)