How to save your home from the menace of cracks?
When you build your dream house it is very disheartening to see the ugly cracks spreading on its surface. While smaller cracks may not pose a serious threat to the house, some of the bigger cracks may be a sign of structural damage. The occurrence and development of such cracks are due to the differential stresses set up in the component of the house. The differential stresses results due to external loads and It can also happen because of foundation movement and settlement of soil, thermal movements, moisture changes. This kind of stress also develops due to chemical action like corrosion of reinforcements, moisture or dampness on the walls, the growth of vegetation on the structure etc.
Here we discuss the basic causes and their remedies for cracks in the house.
Dampness on the walls
Materials like concrete, mortar, bricks, and timber, etc are used for constructing a house. All of these materials tend to expand on absorbing moisture and shrink on drying which can affect the stress in different parts of the house. Therefore the presence of water content in the walls can develop cracks on walls.
To remove the moisture content from the walls you need to do proper leak-proofing, have proper ventilation and fix the damp area with waterproof putty or plaster.
The materials used in construction tend to expand on heating and contract on cooling depending on their properties. Because of this expansion and contraction of materials due to a sudden change in temperature of surroundings, internal tensile stresses of structure increase or decrease. Hence it develops the cracks on the walls. The change in temperature of materials is also known as a thermal movement.
To control the temperature you need to have proper insulation and keep your house safe from the direct sunlight.
Corrosion of Reinforcement
One of the major reasons for the cracks observed in recent RCC building is due to the corrosion of steel. In early stage of the construction, they do not pose any threat to the safety of the structure. But corrosion in the form of rust is like cancer for all the steel reinforcements used in RCC, and it creates a vicious circle.
To reduce this problem you need to use high-quality cement, good quality reinforcement, better grade of concrete, adequate cover to reinforcement good workmanship.
Unstable Foundation & Settlement of Soil
The movement of settlement of soil which leads to the sudden shift in foundation causes the shear cracks in the structure. The cracks in walls occur on the beams due to different bearing pressure on the construction. It happens when bearing pressure on soil which is greater than Soil Bearing Capacity.
The frequent change in moisture of soil underneath the foundation cause the change in the capacity of soil and hence due to the foundation movements, cracks appear in the house.
To tackle this situation you need to take some preemptive measures to maintain the soil bearing capacity. Firstly check the soil quality and use proper means of settlement to give soil the required strength, also use high-quality cement with high grade and good quality reinforcement.
Poor quality cement
Due to the poor quality of cement in construction cracks could develop on the wall surface. It can damage the structural integrity of the building and make it susceptible to other forms of damage. Low and excessive cement content may also result in uneven expansion and shrinkage in concrete that will cause structure to fail and at times even damage block work.
To avoid this the wall should be strictly done with high-quality cement mortar of mix 1:6 or around the same. Use defined boxes to measure the quantity of cement and sand into a prescribed mixture before plastering.