Party Wall

In some jurisdictions, an adjoining landowner who uses a wall built partly on his or her land by the other adjoining landowner has no duty to contribute to the cost of construction of the wall. If there is no evidence of the conditions under which the wall was built, courts presume that each person owns as much of the wall as is situated on his property and has no obligation to contribute to the other's wall.

In some jurisdictions, liability might be imposed by statute. For example, a statute might authorize one of two adjoining landowners to build a wall partly on the adjoining land and require the other landowner to contribute, if and when she used the wall in the construction and support of an adjoining building; until payment would be made, the wall would be owned exclusively by the builder.

The obligation to contribute can, of course, be a provision in the contract between adjoining landowners, but the agreement need not be express. It can be implied from the conduct of the parties, although a contract cannot be implied from the mere assent by one owner to the construction of a wall standing equally on the land of both.