Good Practice. Pit size for excavation should be minimum of 30 cm larger than the PCC size on all sides.

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2 7steps Here you'll learn about the 7 stages of construction that go into the making of your dream home. From 'Excavation & Setting Out' right until 'Flooring'you'll find good practices to follow, the right proportion of material mixes and tips on making your home earthquake resistant.

3 1 Excavation & Setting Out This is the first activity in your building project. It is needed for the foundations and basement of your house, underground water tank, septic tank, laying drainage, water lines & electric cables. Excavating in black cotton soil? Good Practice Pit size for excavation should be minimum of 30 cm larger than the PCC size on all sides. Increase the pit size as the depth increases. As the depth increases, the sides begin to crumble and collapse. Brace the sides with tight shoring work. Never start excavation of 2 adjacent pits simultaneously. Avoid excavation on rainy days.

4 Marking Insist on a marking plan (also known as Centreline drawing) from your architect. Ensure that the drawing details are diligently transferred to the ground. Have the workers place pegs on ground till foundation work is complete and construction of walls is ready to begin. Remember, any mistakes in marking would be permanent and costly to correct. So take great care in marking out your house well.

5 2. Foundation & Plinth The foundation provides anchor to your house; and when Mother Earth grips them tight your structure above the ground becomes stable. The plinth further offsets the load from the walls and distributes it uniformly over the foundation. Good Practice No harm in making your foundations stronger than necessary. After all, your house has to last for generations! Keep a provision for one more storey you might add later. Place the foundation of your house on hard strata, ensure that you carry out excavation until hard strata is reached.

6 Checklist for plinth work Check the distance between masonry walls for room dimensions. " Control the mix of concrete carry out compaction by means of a vibrator. Remove all grass shrubs and loose material from the plinth area. Check and maintain proper sunken levels for bathrooms. Make your house earthquake resistant! Keep the foundation as you normally would, with just a steel rod inserted that goes all the way down into the foundation. Package the steel rod with cement-sand mortar filling all around.

7 Termite attack? No problem! Termites rise from the soil and should be eliminated right there, at the source. Always get anti-termite treatment done for the foundations. Spray the mixture on the bed and sides of the foundation trenches, using 5 litres of the solution per square metre area. Later when the foundation has been raised and back filling done, spray the solution again on the filled up ground. Perfect Mix Prepare a solution of 0.5% Heptachlor, 1% Chlordane, and 1 % Chloropyrifos, and mix with water.

8 3 Brickwork Bricks are one of the most common building materials. To build a strong house, use good quality bricks. Clay is the most common material used in the making of bricks. Make your house earthquake resistant! Avoid formation of fault lines i.e. the bricks should not overlap in a straight line. Keep the orientation of bricks different for each layer. Where should you place doors and windows? Do not keep doors and window openings close to a corner. Keep every opening, door or window, at least 2'from a corner. Keep a minimum distance of 2' between adjacent openings, such as for example between a door and a nearby window on the same wall. Avoid too many openings on the same wall. For a 10' room, the total opening size should not exceed 4', in a single-storeyed house Keep the lintel band continuous; ideally at plinth level, at sill level, and at the level above the doorway.

9 How to test for a good brick? Drop a brick vertically from a height of 1 m. A good quality brick will not break. Strike two bricks against each other. Good quality bricks will produce a clear ringing sound on contact. Perfect Mix For a 4" thick wall (partition walls in the middle of the house), keep mortar proportion as = 1:4 (cement:sand) For a 9" wall (outer wall), keep mortar proportion as = 1:6 (cement:sand) Good Practice Begin work at the corners, first to a height of 3 or 4 layers with base extending in steps. Place all bricks on their bed. The depression on top provides space for the mortar to bond well. Use line-string, plumb bob, and spirit level for checking alignment, and to keep vertical and horizontal lines straight. Soak your bricks in water for 8 hours at least before use, else it will absorb moisture from mortar.

10 Plastering protects the surface of the masonry from the elements, especially rain. It provides lateral stability by binding all bricks and also protects the joints. Perfect Mix Outside plaster = 1:4 (cement:sand) Internal plaster = 1:5 Roof plaster = 1:3 Good Practice Keep the wall slightly wet before starting the plastering. Dry walls absorb plaster, this leads to shedding of plaster after some time. Do not prepare entire mix for the day at one go. Prepare in small quantities so that it is used up in an hour's time. Use chicken wire mesh for plastering joints between concrete and brickwork. Ensure continuous curing for days.

11 This is a commonly followed roofing practice, and refers to laying a slab of Reinforced Cement Concrete (RCC) on the supporting walls, columns, beams of the house. Make your house earthquake resistant! Provide for a band with steel rods at plinth level, i.e. just where the wall starts above the foundation. Provide for a band also at lintel level i.e. above door/window level, running all through the building. 1 Strengthen all corners and junctions with steel rods going down into the foundation. Perfect Mix The composition of concrete for slab casting works should be = 1:1.5:3 (cement:sand:coarse aggregates)

12 How to avoid leakage in the roof? Use concrete in the correct proportion with water proofing compounds also added in the mix. Compact the concrete well with an appropriate vibrator (surface/plate vibrator) to free all air pockets. Good Practice Use cover blocks (tied to the steel bars) to keep the bars in place, and to prevent them from exposure to air. Treat the face of formwork with form release agents, a mix of diesel and grease for example. Keep the surface continuously moist for days. Keep the formwork tight and leak-proof, to prevent cement-sand-water from leaking. Steel rods should be free of rust, oil, paints, or mud.

13 13 Waterproofing 6. Waterproofing Waterproofing maintains the appearance of the building and increases the life of the structure. For good water-proofing work, selection of quality material and workmanship is important. Waterproofing your terrace? Here's how Prepare the surface Chisel away the extra mortar gathered on the terrace using a chisel and hammer. Clean the terrace thoroughly with water. Add 1 bag of cement to 100 litres of water, stir the mixture to get a consistent cement slurry. Spread the slurry on the terrace and allow it to penetrate uniformly over the cleaned surface. Brick bat coba coat Fix brick bats in cement mortar layer of 1:6 proportion with water-proofing compound in a slope of 1:150. Fill cement mortar in 1:4 proportion with waterproofing compound in the brick bat joints. Ensure a rounded lining near the rain water pipe. Cure for 7 days. Final coat Spread cement mortar in 1:4 proportion with water-' proofing compound over the brick bat coba, and level surface with a wooden float. Apply thick cement slurry over leveled surface, along with water-proofing compound for a smooth finish.

14 Make a tile pattern 1' x V of 3 mm thickness, to prevent cracking of the top layer. Clean and cure the final coat for 21 days with at least 6" water standing on the water-proofing. Water-proofing your chajja? Here's how Clean the top of the chajja, and chisel extra mortar if any. Apply a thick cement slurry over the top of the chajja. Apply 1:1.5:3 metal screed coat over the slurry. Ensure a rounded lining near the rain water pipe. Cure for 7 days. Apply a finishing coat with cement mortar in 1:4 proportion with the water-proofing compound. Pre-monsoon precautions! Avoid leakages before the rains set in Clean all rain water pipes. Clean terrace and do not allow any organic material to remain on surface.

15 Perfect Mix 1:6 (cement mortarrwater-proofing compound) for laying brick bats. 1:4 (cement mortar:water-proofing compound) in brick bat joints. Remember! In your enthusiasm to damp-proof your house, do not exceed the dosage quantities. Excessive quantity of the water-proofing compound or admixture will have a negative effect on quality of concrete.

16 Flooring 16 flooring The floor of your house is the basis for its residents, the furniture and equipment; in short it provides a horizontal surface for your lifestyle. All floors should provide strength and stability, resistance to dampness, excellent appearance, and should be free of maintenance. Choose your floor finish Cement concrete floors Wears well, and is easy to clean and maintain. For lesser floor thicknesses, use aggregate upto 1/2"size. Perfect Mix 1:1.5:3(cement:sand:coarse aggregates) Terrazzo/Marble chips f loori ng Marble chips are laid on a layer of cement concrete. The topping (also known asterrazzo) is laid while the under layer is still plastic, but has hardened sufficiently enough. Perfect Mix Under layer = 1:2:4 (cement:sand:coarse aggregates), 1" thick Top layer = 3:1 (cementmarble powder); 1.5:1 (marble chips:binder)

17 Tile Flooring Tile flooring makes for a beautiful appearance, and can be executed quickly. Ceramic and vitrified tiles are very popular; they don't require grinding or polishing and are strong. Perfect Mix 1:6(cement:sand) Laying tiles? Good Practice Immerse tiles in water 3-4 hours prior to laying. Aminimumof7 days of curing is recommended after tiles are fixed. Lay your tiles after the bedding has been sufficiently levelled and lightly compacted. Flooring for your balcony? Good Practice Give a proper slope to allow water to flow through the spout. Fix the spout 10"away from the side wall to prevent water from stacking inside the balcony area.

18 Know your Materials Brick Bricks are one of the most common building materials. To build a strong house, use good quality bricks. Clay is the most common material used in the making of bricks. You'll find 2 kinds of bricks in your neighbourhood country bricks and wire cut bricks. Wire cut bricks are costlier than country bricks.to give a fair idea of the cost, wire cut brick are costlier to country bricks by 25-30%. How to test for a g o o d brick? Strike two bricks against each other. Good quality bricks will produce a clear ringing sound on contact. Drop a brick vertically from a height of 1 m. A good quality brick will not break. Keep a brick immersed in a water tank for 24 hours and then check its weight. If there is more than a 15% difference between the dry and wet weights of the brick, it is not fit for use. E.g. Assume the weight of a dry brick is 2 kgs. After soaking in water for 24 hours, if it weighs 2.3 kgs or more, the brick is not fit for use.

19 Building a wall? Good Practice Ensure the bricks have been soaked in water for 8 hours before beginning work. Place all bricks on their bed. The depression on top provides space for the mortar to bond well. Use line-string, plumb bob, and spirit level for checking alignment, and to keep vertical and horizontal lines straight. Begin work at the corners, first to a height of 3 or 4 layers with base extending in steps. Joints should be raked and finished with a trowel. Build to a maximum of 1 m wall height daily. Remember! Keep systematic bond throughout the brickwork, vertical joints should be staggered and not continuous. For a 4" thick wall (partition walls in the middle of the house), keep mortar proportion as = 1:4 (cementsand) For a 9" wall (outer wall), keep mortar proportion as = 1:6 (cement:sand)

20 These are small pieces of stone gravel which give strength to the concrete. Generally, they come in 2 sizes- 20 mm and 10 mm. Stone dust is used as fine aggregate and stone pieces as coarse aggregate. They make 70-75% of total volume and give body to the concrete. Good Practice Ensure that the pieces do not contain clay, mud or dirt particles. The space between big pieces of aggregates should be filled up by small pieces. The vacant space between small pieces should be filled up by sand. This makes the concrete dense. Generally 20 mm and 10 mm aggregate ratio of 60:40 and 70:30 offers best results.

21 Buying aggregate? Remember. Suppliers will quote the price of aggregates per cubic foot or cubic metre or even per truck. At the time of delivery do measure the quantity. Do not procure aggregates of uniform size, they tend to leave voids in between, which reduces total weight. Watch Out! If the content of 10 mm stone is lowered, sand requirement goes up and will consequently require more water. In turn, water quantity per bag of cement will increase, leading to late setting and poor quality of concrete.

22 Steel Although concrete has good compressive strength, it does not withstand tension or bending stresses by itself. To overcome this, steel rods are placed inside concrete to provide strength. It forms the basis of the concrete structure and is generally laid out in a circular cross section called Reinforced Cement Concrete (RCC). For building your house you would need 6 to 20 mm diameter bars. Thermomechanically treated (TMT) bars with added features (twisted or ribbed steel) are also available. Every bar is of 11 m length and weighs 0.64 kg/m.

23 Lap length (the overlap between a bar and the next extension) should be 50 times the diameter of the bar. Stagger the laps for even distribution of strength; a maximum of 50% bars should be lapped per section. If required lap length is not available at the junction due to space/material constraints, use couplers or weld properly. Anchorage length (extra length of steel from one structural member into another at the junction) should generally be equal to Lap length.

24 Sand Sand is an ingredient of mortar for plastering brickwork, and is also used as aggregate to fill voids while concrete is made. How to check for quality? Take a handful of sand and press it in your palm. If there is mud, dirt or any other contamination, it will stick to your palm. Such sand has too much silt and clay to be of use in construction. Try this simple test. Fill a glass container with sand upto half its capacity and pour clear water three quarters full. Shake it vigorously and let it settle for half an hour. Clean sand will settle at the bottom immediately. Clay or silt in the sand will make the water muddy and will settle slowly on top of the sand (add one teaspoonful of sand to quicken the process). The thickness of silt/clay layer should not be more than 4% of the sand layer. If higher, the sand must be washed before use. Good Practice Clean sand through a wire mesh so that mud pieces, shells and other impurities are well isolated. Watch Out! Wet sand can cause problems! Sand that contains moisture before mixing causes the particles to increase in volume. This is called Bulking. For example, sand with 6% moisture content shows around 30% bulking. This means you need to add approximately 30% extra sand. You would therefore also need to correct the volume of water in the mix. Construction labourers tend to add a lot of water, sometimes more than required. If the sand being used is already wet, then more water will weaken the mix. If you find the sand being used is already wet, instruct your contractors to add water judiciously. The sand you use should have no clay, dirt, mica, or sea shells!

25 Cement Cement is a binder, which along with water binds together a mixture of sand and aggregates to make concrete. Proper selection of cement guarantees a strong and stable construction. Cement types- what to use and when? Ordinary Portland Cement (OPC) Available in grades like 33,43, 53. Good for brick joining, plastering. Blended cement Also known as Composite cement, or Pozzolona cement. Good for all general construction, such as concreting, brick joining and plastering.

26 Why use Blended Cement? It gives concrete better strength and durability. Reduces leaching (washed up lime that comes out and weakens construction. Prevents crack formation as less heat is let out as it sets. Resists chemical attacks from elements in ground, air or water. Requires less water to prepare concrete. In comparison to OPC, it uses 10% less water. Did you know? What 33,43 & 53 grades if cement mean? 33,43, and 53 grade means that at 28 days, the cement mortar cube has a compressive strength of at least 33, 43, and 53 MPa {Mega Pascals) respectively. Does the colour of cement have bearing on its quality? No, quality is determined by the colour and quantity of raw materials used. Does a higher grade of cement ensure better results? The grade only indicates its compressive strength at 28 days! But cement continues to increase in strength beyond that period of time for much longer. Blended or Composite cements render higher strengths for a longer duration.

27 How can I store cement safely? Water is enemy no.1 of cement during storage. Ensure that cement is kept free of moisture while storing. Storage area should have concrete floor raised at least 150 mm above ground level, with airtight doors and windows. At site, cement should be kept on a raised platform and covered with a tarpaulin. Should I use cement that sets quickly? Quick setting of cement depends not only on the quality of cement but also on the quantity of water used in preparing the mix. Wait that little extra for your cement to set slowly and gain in strength. Do not look for premature results, give concrete adequate time to set properly and attain full strength. deteriorate. So move cement in and out of the store in a first-in-first-out method. Use cement within 2-3 months from the date of manufacture. How to test for good quality cement? Take a little cement and make a paste adding 1/4th quantity of water. Make little cubes of 50 x 50 x 20 mm size. Leave aside for a day. Test the blocks to see how easily they break. If the cement is of good quality the blocks will be firm and will not crumble or break if you try to crush it with the pressure of your lingers.