1911 Encyclopædia Britannica/Party Wall
PARTY WALL, a building term which, in England, apart from special statutory definitions, may be used in four different legal senses (Watson v. Gray, 1880, 14 Ch. D. 192). It may mean (1) a wall of which the adjoining owners are tenants in common; (2) a wall divided longitudinaDy into two strips, one belonging to each of the neighbouring owners; (3) a wall which belongs entirely to one of the adjoining owners, but is subject to an easement or right in the other to have it maintained as a dividing wall between the two tenements; (4) a wall divided longitudinally into two moieties, each moiety being subject to a cross easement, in favour of the owner of the other moiety. Outside London the rights and liabilities of adjoining owners of party walls are subject to the rules of common law. In London they are governed by the London Building Act 1894. A tenant in common of a party wall is entitled to have a partition vertically and longitudinally, so as to hold separately (Mayfair Property Co. v. Johnston, 1894, 1 Ch. 508); each owner can then use only his own part of the wall. By the London Building Act 1894, § 5 (16) the expression “party wall” means—(a) a wall forming part of a building and used or constructed to be used for separation of adjoining buildings belonging to different owners, or occupied or constructed or adapted to be occupied by different persons; or (b) a wall forming part of a building, and standing to a greater extent than the projection of the footings on lands of different owners. Section 87 regulates the rights of owners of adjoining lands to erect party walls on the line of junction. Sections 88-90 determine the rights of building owners to deal with party walls by underpinning, repairing or rebuilding. The act also contains provisions for settling disputes (§§ 91-92), and for bearing and recovering expenses (§§ 95-102). Part VI. of the act regulates the structure and thickness, height, &c., of party walls.
See A. R. Rudall, Party Walls (1907).