Despite its jaunty name, a party wall is not a vertical place of amusement but simply a single common wall on a property line, built to support two buildings. The people who created party walls and party wall agreements a century or two ago didn’t consider what would happen if one of the two adjoining owners should want to add on to the party wall to support more floors, or to take the party wall down and redevelop a property. Raising and razing party walls both present practical problems.
Lawsuits about party walls go back to at least 1813 and a decision of the English Court of Common Pleas in Matts v. Hawkins, 5 Taunton 20 (1813). Twenty-five years earlier adjoining owners had built a party wall. Ten years before the dispute got to court, Hawkins demolished his building, leaving the party wall standing. Hawkins then built a shed against the party wall. Later on Matts, whose building still stood, began to extend the party wall upward to support a floor that Matts was adding to his building. Hawkins tore down the wall extension. When Matts started to rebuild it, Hawkins tore it down again, and Matts sued Hawkins for trespass. Hawkins argued that they were tenants in common as to the wall, and that as a tenant in common Hawkins could not be liable in trespass to Matts because the wall belonged to both of them. The court rejected the argument of Hawkins and held that Matts and Hawkins each had some rights to the portion of the wall on the property of the other, which the court described as being easements.
One lesson of Matts v. Hawkins and the many decisions on party walls since 1813 is that a good party wall agreement should cover three points:
- How will the owners divide the cost to maintain and repair the party wall?
- Can either neighbor extend the wall upward, and if so, then can the extending neighbor build the extension on both properties?
- What happens to the wall if one building is destroyed or is demolished?
Owners who want to be able to replace the party wall with a new party wall can use this clause to describe when and how each will pay for the new wall:
If the North Building and the South Building are both demolished or destroyed, then the North Owner and the South Owner will replace the party wall with a new party wall designed and built to be capable of supporting buildings on the North Tract and the South Tract of up to ___ floors above ground. The party that replaces its building first (in this section, the “Building Party”) will pay the cost to build the party wall and furnish an accounting of the cost to the other party. The second party will reimburse the Building Party for one-half the cost to build the party wall before the second party begins construction on the second party’s building. The second party will reimburse the Building Party for one-half the cost to build the party wall whether the second party uses all or part of the party wall.