Home building basics

Home building basics

  • Foundation

    • If the foundation of your building is poor, then the entire structure will collapse or sink. Keep these pointers in mind to ensure a strong foundation:

    If the foundation of your building is poor, then the entire structure will collapse or sink. Keep these pointers in mind to ensure a strong foundation:

    • The foundation should rest on firm soil and it should be taken to a minimum depth of 1.2m from the ground level.
    • If the soil is loose and/or if the excavation depth is more, the sides of excavation should be supported to prevent it from collapsing.
    • The area of the foundation should be sufficient to transfer the load safely to the ground on which it rests.
    • The area of foundation depends on the load carrying capacity of soil. It is important to mark the location and size of the foundation before excavation.
  • Marking and Excavating the Foundation

    • Ensure correct marking of the foundations for new walls so that they are the right size and in the right position to bear the weight of the wall.
    • Ensure correct marking of the foundations for new walls so that they are the right size and in the right position to bear the weight of the wall.
    • Obtain the layout plan/centre-line drawing from the engineer and establish the centre-line of the longest outer wall of the building as a reference line between the pegs driven into the ground.
    • Mark all trench excavation lines with respect to the centre lines of walls.
    • Ensure that the excavation done is true to levels, slope, shape and pattern.
    • Consolidate the bed of excavation by watering and ramming. Soft or defective spots should be dug out and filled with concrete.
    • Brace the sides of excavation with tight shoring work for deep excavations to avoid collapsing of the sides of the excavation area
  • Anti-termite treatment

    • Termite infestation can weaken structures and damage wooden surfaces. Start the anti-termite treatment before the construction begins. Here's what you need to know to keep your home free of termites:

    Termite infestation can weaken structures and damage wooden surfaces. Start the anti-termite treatment before the construction begins. Here's what you need to know to keep your home free of termites:

    • The soil around the foundation should be treated up to the plinth level with appropriate chemicals.
    • The chemical barrier should be continuous and complete.
    • Treatment can be done pre, during and post construction stages.
    • Care should be taken to ensure that the chemicals do not contaminate the domestic water sources.
  • Cement Storage

    • Cement is highly sensitive to moisture. On exposure to moisture, it becomes hard. Here's how cement should be stored:

    Cement is highly sensitive to moisture. On exposure to moisture, it becomes hard. Here's how cement should be stored:

    • Cement should be stored in water-proof sheds/buildings.
    • For temporary storage at sites, cement bags should be stacked on a raised dry platform and covered with tarpaulins/polythene sheets.
  • Aggregates

    • Poor quality aggregates will result in inferior concrete thus affecting the durability of the structure. Here are some handy pointers you need to keep in mind:

    Poor quality aggregates will result in inferior concrete thus affecting the durability of the structure. Here are some handy pointers you need to keep in mind:

    • Aggregates should be hard, strong, chemically inert and free from harmful materials.
    • If flaky and elongated coarse aggregates/jelly are present in excess quantities, it leads to low concrete strength.
    • Cubical and rough textured aggregates are preferred over other types.
    • Sand should be free from silt, clay lumps, mica, etc.
    • Presence of any of the aggregates in excessive quantities adversely affects the setting, hardening, strength and durability of concrete.
  • Masonry Walls/Brick Work

    • You house will not be considered safe if its walls are not strong and sturdy. You need to adhere to the following tips:

      You house will not be considered safe if its walls are not strong and sturdy. You need to adhere to the following tips:

    • Bricks/blocks should be laid on a full bed of mortar.
    • The joints should be fully filled and packed with mortar.
    • Vertical joints should be staggered.
    • The brick work should be cured well to make it strong.
  • Centering and formwork

    • Weak and unstable centering and formwork may lead to injuries/loss of life in addition to material loss. Here's how centering and formwork should be done:

    Weak and unstable centering and formwork may lead to injuries/loss of life in addition to material loss. Here's how centering and formwork should be done:

    • Centering should be strong enough to hold the fresh concrete till it hardens.
    • To ensure stability, centering should be supported at specified intervals with props that are adequately braced.
    • Gaps between the centering sheets should be sealed to prevent leakage of slurry, which otherwise would result in honey combed concrete.
  • Reinforcement bars

    • Reinforcement bars are a vital component of RCC. It's important to choose the right steel and place it right to prevent cracking or even destruction of the RCC members.

    Reinforcement bars are a vital component of RCC. It's important to choose the right steel and place it right to prevent cracking or even destruction of the RCC members.

    • When you're procuring steel, make sure you get it from a reputed manufacturer.
    • Wrongly positioned reinforcement bars are ineffective and lead to the failure of RCC elements.
    • While joining the bars, adequate lap length should be maintained and the laps should be staggered.
    • Ensure that there is no congestion of reinforcement bars and that the bars have sufficient concrete cover.
  • Compacting

    • Well-made concrete may go waste if it is not compacted well into place and cured inadequately. Here's how you should go about with the compacting:

    Well-made concrete may go waste if it is not compacted well into place and cured inadequately. Here's how you should go about with the compacting:

    • Improper compaction reduces the strength and hence the durability, due to the presence of air voids.
    • Over compaction leads to segregation and movement of cement paste upwards, making it weak.
    • Effective compaction results in closer packing of ingredients, leading to denser concrete.
    • Curing should start early and should be continued for a sufficient period to ensure that it develops the desired strength and doesn't crack.
    • Avoid intermittent curing as it is harmful.
  • Plastering

    • Wall plasters that have unsightly cracks and spoilt interior/exterior finishes are quite common. Here's how you can avoid it:

    Wall plasters that have unsightly cracks and spoilt interior/exterior finishes are quite common. Here's how you can avoid it:

    • Plastered surfaces develop cracks and sometimes disintegrate due to lack of proper adhesion.
    • Surface preparation plays a vital role in ensuring the adhesion. The surface should be free from any loose particles, dust etc., and the joints between the bricks/blocks should be properly raked.
    • Lean mixes are preferred for plastering as rich and weaker mixes tend to develop cracks.
    • Normally, plastering should be done in two coats leaving adequate time between the coats.