Lateral support means, physical support to prevent sideways movement.  In property law, the term lateral support is the right of a landowner to physically support his/her land in its natural state by both adjoining land and underground structures.  It is the right of a land owner assuring that the adjoining land will provide support against any slippage, cave-in or landslide.  The right to lateral support is an absolute right.  When there is any interference in this right, it is a strict liability in a tort action.  If an excavation done by adjoining owner damage landowner’s property, the adjoining owner is liable for the damages.

When the adjoining owner excavate into the soil for foundation, basement or leveling, a retaining wall is to be constructed to prevent a collapse.  The most common need for lateral support is in the construction of deep basement excavations.  Courts order to pay the entire value of damage if there is any destruction because of delay in constructing retaining wall.  For instance, a developer excavated into a hill to create a pad for an apartment building and delayed putting in the retaining wall.  Cracks appeared in the buildings next to the digging site and neighboring buildings toppled into the hole.  Court ordered that the developer should pay the entire value of the buildings which were destroyed.

When improvements on the land have suffered a loss of support, courts will not apply a strict liability standard.  In lateral support cases involving improvements, courts limit the strict liability standard and look whether the improvements contributed to or caused the subsidence.  In such cases courts apply strict liability only if the land would have subsided without the improvement.