What Is a Neighbour Lateral Support Agreement and When Do You Need One?

The neighbour-relations law (Lateral Support Act 25 of 1995) governs work affecting walls shared with neighbours, walls built on the boundary, and excavations within three or six metres of an adjoining property. Get it right and your build proceeds smoothly. Get it wrong and a neighbour can stop your project with an injunction.

What is a party wall?

A party wall is a wall standing on land of two or more owners, or a wall on one owner's land which is used by adjoining owners to separate their buildings. The Act also covers:

• Party fence walls — boundary walls not part of a building
• Party structures — floors, ceilings, and partitions between flats
• Excavations within 3 m of an adjoining building, or within 6 m where the excavation goes below a 45° line from the neighbour's foundation

When does the Act apply?

You need to serve notice if you are planning to:

• Cut into a party wall to insert a beam (e.g. for a side return extension)
• Raise the height of a party wall
• Demolish and rebuild a party wall
• Underpin a party wall
• Build a new wall on the boundary line
• Excavate near an adjoining building (3 m / 6 m rules above)

Common projects that trigger the Act in a typical Johannesburg terrace: rear extensions, loft conversions involving a party wall, basement digs, side return reconfigurations.

The notice and consent process

1. Building Owner serves notice on Adjoining Owner(s) — at least 2 months before work for party wall notices, 1 month for excavation notices.
2. Adjoining Owner responds within 14 days:
   • Consent — work proceeds.
   • Dissent — surveyors are appointed (one each, or a single "agreed surveyor").
   • No reply — dissent is deemed.
3. Surveyors agree a Neighbour Support Agreement — a binding document setting out scope, condition schedule, working hours, and access.
4. Work proceeds in accordance with the Award.

Costs

Building Owner pays unless the Award says otherwise. Typical costs in 2026:

• Notice preparation by a neighbour-relations consultant: R2,000 – R5,000 per notice
• Agreed surveyor (one surveyor acting for both parties): R18,000 – R36,000
• Two surveyor route (one each): R36,000 – R80,000 typically, more for basements
• Schedule of condition survey of adjoining property: R8,000 – R16,000

Basement projects often run R100,000 – R300,000 in party wall fees per neighbour because of the technical complexity and risk to adjoining properties.

What the Award covers

• Description of authorised work
• Schedule of condition photographs of the adjoining property
• Working hours and access rights
• Insurance requirements (typically R100m – R200m public liability)
• Method statements and structural drawings
• Damage repair provisions

Common mistakes

• Starting work without notice. Your neighbour can apply for an injunction. Courts grant them routinely.
• Treating it as adversarial. Most neighbours consent if approached early and politely. Save formal notices for when consent isn't forthcoming.
• Skipping the schedule of condition. Without one, every pre-existing crack becomes "your" crack.
• Hiring the cheapest surveyor. A poor Award leaves ambiguity that costs more later.

Programme impact

From notice service to a fully agreed Award typically takes 6–10 weeks for straightforward extensions, 10–16 weeks for basements. Build it into your programme. Don't apply for Local Authority Building Control approval and then discover you forgot the Party Wall.

MCFAR works regularly with neighbour-relations consultants on basement, extension, and underpinning projects. Speak to us about your scheme.

Frequently Asked Questions