property

party wall

A party wall is a single wall built on or along the boundary line between two adjoining properties and shared by both owners. It is common in townhouses, row homes, and attached commercial buildings. Each owner typically owns the part on their side and holds an easement in the other part for support. Maintenance and repair costs are usually shared, often under a written party wall agreement.

Exam tip
Exams usually treat a party wall as an example of a cross easement: each owner has a right of support in the neighbor's half of the wall.
Example
Two attached row houses share one brick wall on the lot line. When the wall's foundation cracks, both owners split the $6,000 repair bill.

Related terms & state variants

Sources

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Last verified: 2026-10-23