At the rear of two buildings there is a very old boundary wall which acts as a party wall and is shared between the two buildings. There are no records of where the boundary lies so we assume it runs down the middle of this wall.
On one side of this wall, there is Neighbour One’s garden. On the other side of the wall, there is a single storey storeroom created in the 1960s by roofing over the garden of Neighbour Two. So the storeroom belongs to Neighbour Two. There is probably some tanking or a void between the storeroom and the boundary wall, but the boundary wall does support the roof of the storeroom.
Thus, it will be noted that the shared boundary wall has to be used for two purposes – to act as a garden wall for Neighbour One and to act as part of a flat-roofed building for Neighbour Two. The only access to this wall is through Neighbour One’s garden. There is no opening from the storeroom into Neighbour One’s garden – the wall is blank.
If the two neighbours differ in their view as to how to maintain the wall, how could this be resolved, preferably without recourse to party wall surveyors and serving formal notices? And does the Access to Neighbouring Land Act apply here, even though the boundary wall is agreed to be a shared party wall and Neighbour Two cannot prove or claim full ownership?
Original walls dividing rear gardens will tend to be built equally astride the boundary and if both neighbours agree it’s probably best to proceed on the basis that it is a party fence wall.
If the wall is defective or in want of repair, one of the parties will need to take the lead (they would become known as the ‘building owner’) and serve a Party Structure Notice. The notice should set out what is proposed and how they think the costs should be apportioned. If the recipient of the notice (known as the ‘adjoining owner’) agrees with what is proposed they should consent to the notices and pay their contribution when presented with an invoice upon completion of the works.
If the adjoining owner does not agree with what is proposed they they can dissent to the notice and trigger a dispute – both owners would then have to appoint surveyors (or a single surveyor) to determine that dispute. Section 11(5) of the Act sets out how the costs of the works should be defrayed between the owners i.e. according to the use which the owners respectively make of the wall concerned and responsibility for the defect or want of repair concerned.