Adjoining owner. The neighbour whose property is affected by the work.
Adjoining occupier. Someone who lives in or occupies the neighbouring property but may not own it, such as a tenant.
Agreed surveyor. One surveyor appointed jointly by both owners to settle matters impartially.
Award. The binding document made by the surveyors, setting out what work may be done, how and when, recording the neighbour's property and dealing with costs. Commonly called a party wall agreement.
Building owner. The owner who wants to carry out the work.
Counter notice. A notice from the adjoining owner, served within a month, asking for extra work such as chimney flues, piers or deeper special foundations to suit their own future plans.
Deemed dispute. The dispute that automatically arises when a neighbour does not consent to a party structure or excavation notice within 14 days.
Dissent. Declining to consent to a notice, so that surveyors settle matters.
Excavation notice. Short for notice of adjacent excavation, served before digging close to a neighbour's building.
Line of junction. The boundary line between two properties.
Making good. Repairing damage caused by the work.
Party fence wall. A masonry wall astride the boundary that is not part of a building.
Party structure. A party wall, or a floor, partition or other structure dividing buildings, or parts of buildings, that have separate staircases or entrances.
Party structure notice. The notice used before working on a party wall or other party structure. It needs two months' warning.
Schedule of condition. A record, with photographs, of the neighbour's property as it was before work began.
Security for expenses. Money set aside by the building owner before work starts, at the neighbour's request, to cover finishing the job or making good if things go wrong.
Special foundations. Foundations reinforced with steel, such as reinforced concrete, which need the neighbour's written consent to be placed on their land.
Third surveyor. A surveyor selected at the outset by the two appointed surveyors to settle any disagreement between them, or between either owner and a surveyor.
Where this comes from in the Act
Links go to the official text of the Party Wall etc. Act 1996 on legislation.gov.uk.