There are many types of underpinning methods. They are all relatively affordable and suitable
for shallow subpinning. They are suitable for buildings with high foundation loads. Mass
concrete underpinning involves filling voids in the foundation with concrete. This method does
not require heavy machinery, so the cost of labour is relatively low. This method is suitable for
buildings that are not fully submerged in water.
Another type of underpinning is the piles. These are driven along the foundation structure’s side.
Then, they are capped with a steel cage and fresh concrete is poured into them. The process of
underpinning causes minimal disruption to your building. Mini-piles may be used in cases where
steel cages cannot be installed. Because they can withstand high loads and maintain structural
integrity, they are ideal for reshaping existing buildings.
Underpinning can be required when the foundation has cracked or is weak. Underpinning
strengthens the foundation by replacing soil with concrete and increasing its depth. This involves
careful design, safety procedures, and methodology. It may be required due to poor soil
properties or subsidence. Sometimes the foundation has moved due to natural causes. Although
the process can be costly, it is necessary. There are many advantages to underpinning your
building.
Another type of underpinning, also known as restumping and reblocking is called. Restumping
involves the replacement of stumps in the foundation. Reblocking involves reinforcing concrete
slabs. Although it is disruptive and expensive, it provides the best foundation for your home.
However, it is not suitable for every foundation type. It is important to consider all options before
making a final decision. The ground condition will dictate the type and amount of underpinning.
Underpinning can be used to support structures, as well as providing structural support. For
example, in New York, a historic hotel reopened as a Grand Hyatt in 1979. The Grand Central
Station subway structure supported the original building. The building was reopened to
passengers after the renovation. The building was able function as intended. The renovation
made the space accessible and improved the flow of people out of the building.
Underpinning can be necessary if the soil beneath the footing of a structure has lost its bearing
capacity. This can happen due to nearby excavation. It can also occur due to fluctuations in the
water table. Insufficient bearing capacity of the soil can lead to settlement. As a result, the
timeframe for underpinning is determined by the severity of the settlement. It can take many
months to repair damage to the home.
Subsidence and water levels are the most common reasons a house is underpinned. Additional
floors or extensions could also be a reason for underpinning a home. Underpinning serves the
main purpose of distributing the building’s weight to its support. The mass concrete technique
involves digging out sections below the foundation, and then filling them up with concrete. This
method is long-lasting and traditional, but it can be used for shallow foundations. However, it is
more expensive and carries a higher risk of a foundation failing.