(765 ILCS 140/1) (from Ch. 111 1/2, par. 3301)

Sec. 1. Each adjacent owner is entitled to the continuous lateral and subjacent support which his land receives from the adjoining land, subject to the right of the owner of the adjoining land to make proper and usual excavations on the same for purposes of construction or improvements, under the following conditions:

1. Any owner or possessor of land intending to make or to permit an excavation to be made on his land shall give due and reasonable notice in writing to the owner or owners of adjoining lands and of adjoining buildings and other structures stating the depth to which the excavation is intended to be made and when the excavation will begin. If the excavation is to be of a depth of not more than the standard depth of foundations, as herein defined, and if it appears that the excavation is to be of a greater depth than the walls or foundations of any adjoining building or other structure and is to be so close as to endanger the building or other structure in any way, then the owner of the building or other structure on the adjoining land shall be allowed a reasonable time, but in no event less than thirty (30) days, in which to take measures to protect the same from any damage or in which to extend the foundations thereof, and he must be given, for the said purpose, a license to enter on the land on which the excavation is to be or is being made.

2. Any owner or possessor of land upon which an excavation is made, who does not comply with the provisions of subparagraph 1, when so required, is liable to the owner of adjacent property for any damage to the land or to any buildings or other structure thereon arising from such excavation, and is also liable to occupants and tenants of the adjoining land or structures for any damage to their property or business, proximately resulting from injury to such land or structures, caused by the failure of such owner or possessor to so comply.

3. In making any excavation, reasonable care and precautions shall be taken to sustain the adjoining land as such, without regard to any building or other structure which may be thereon, and there is no liability for damage done to any building or other structure by reason of the excavation except as herein provided or otherwise provided or allowed by law.

4. Standard depth of foundations, as used herein, is a depth of eight (8) feet below the established grade of a street, highway or other public way upon which such land abuts, or if there is no established grade, below the surface of the adjoining land.

5. If the excavation is intended to be or is deeper than the standard depth of foundations as herein defined, then the owner of the land on which the excavation is being made, if given the necessary license to enter on adjoining land, and not otherwise, shall protect the said adjoining land and any building or other structure thereon, without cost to the owner thereof, by furnishing lateral and subjacent support to said adjoining land and all buildings and structures thereon, in such a manner as to protect the same from any damage by reason of the excavation and shall be liable to the owner of such property for any damage to the land or to any buildings or other structures thereon.

6. The owner or possessor of the land upon which the excavation is being made shall also be liable to occupants and tenants of such adjoining lands or structures thereon for any damage to their property or business, proximately resulting from injury to such land or structures, caused by the failure of such owners or possessor, making such excavation, to fulfill the duty set forth in subparagraph 5.

(Source: Laws 1957, p. 1102.)