Often we can see such defect in the basement of private houses as cracking. Then a question appears – how to fix a cracked foundation?
The main reasons for destruction of foundations:
- subsidence;
- popping of foundation;
- frost heave;
- tipping the foundation.
It is necessary to solve the problem immediately, finding out why a crack appeared and doing repairs.
Methods for foundation diagnosing
First you need to investigate the foundation, to find out the reason for cracking, to determine the speed of propagation of the defect. The most correct research can be done by a special laboratory team. However it costs a lot of money, so you can do it yourself. One of the easiest ways of researching is setting plaster beacons by which it can be determined whether the crack continues to expand. Set 2 or 3 beacons on a crack. If the crack extends the beacons must also crack. As it is also possible to determine the rate of deformation and shrinkage of foundation with the help of these beacons.
Now you should clarify the causes of the destruction
- human activity (for example, soaking a ground and a base with tap water, which leads to freezing and further damages to the structure);
- improper design and construction (low-quality solution, the wrong calculation, etc);
- nature factors (ground water, heaving soils).
Often failures occur due to a strong and non-uniform shrinkage of the house which always occurs in the first years after the house was built. The first signs of the destruction of the base is the appearance of cracks and cavities. In the process of natural shrinkage some minor damage can appear, but in future they will not be getting worse – in this case it will be enough to carry out some cosmetic repairs. But if destruction continues to grow it needs more serious repairing.
Cracks can occur due to laying a foundation above the freezing ground. The degree of deformation of the soil and its influence on the foundation of the house depends on the heaving of the soil. If there are cracks in the foundation, it must be warmed. To do this dig a trench along a house cap, then fill it with fine gravel or coarse sand – these are types of ground which do not expand when it freezes. Over it put a layer of insulation, and then over it do blind area. Before placing blind area, it is necessary to lay the waterproofing. It is advisable to carry out warming of the lateral surface of the foundation.
Repairing a cracked foundation
If the foundation is cracked around all its perimeter, it is necessary to dig a trench around the entire house to a depth of a foundation. Then the surface is cleaned of dirt and old plaster. Then at some distance from the wall attach a metal mesh to basement with the help of anchors. Then concrete the structure layer by layer. Moreover, each layer must be carefully compacted. If the foundation of the house is made of rubble, rubble concrete or reinforced concrete, it should be strengthened by means of concrete broadened clips. To do this, the clips must be carefully associated with the old masonry with the help of anchors. The process is carried out with the expectation that new areas will work together with the old base.
Enhancing and strengthening the foundation
There are also situations where the foundation is fully come into disrepair. Repairing it will require complete replacement. It is necessary to unload the old one maintaining the stability of the house in order to not destroy any of the walls.
You can use the following methods:
- setting the temporary “chairs” which are placed perpendicular to the sleepers of a cracked foundation;
- installation of stone pillars pulling under the walls of the house;
- the use of braces which hold a plinth wall and transfer the loads from the weight of its ground at an angle.
Before you change the base you need to install beacons. If the wall starts to deform or break down it indicates the changes that had occurred. Then dig a pit. The new foundation should be laid on small plots of about 6-7 feet. While deepening of the base it is necessary to strengthen the walls of the house with the help of braces. After strengthening the foundation is undermined and the ground under it is cleared. The walls of the pit are finished with planks, formwork. The sole of the old base is cleaned of dirt, soil, rubble, crumbling concrete. The new and the old foundation are held together by a hard cement mortar with crushed stone. Then continues working with the next section. It is usually allowed to carry out repairs in several sites at the same time in case that the distance between them are more than 20 feet.
So, it is possible to fix a cracked foundation with your own hands. You just need to determine the causes of damage and eliminate them.