When a neighbour dissents (or doesn’t respond) to a Party Wall Notice, the Party Wall etc. Act 1996 requires surveyor involvement. At that point, there are usually two routes:
- An Agreed Surveyor (one surveyor acting impartially for both owners), or
- Two Surveyors (each owner appoints their own surveyor)
Both routes can lead to a valid Party Wall Award—the best option depends on the relationship between neighbours, the complexity of the works, and the level of risk.
What is an Agreed Surveyor?
An Agreed Surveyor is a single party wall surveyor jointly appointed by both the building owner and the adjoining owner. Importantly, they must act independently and impartially, even though one person is handling the process.
Best suited to:
- Straightforward works (typical extensions, loft conversions, standard steelwork)
- Reasonable neighbour relations
- Situations where the neighbour wants reassurance, not confrontation
- Owners aiming to keep process time and costs proportionate
Typical advantages:
- Lower overall cost (one surveyor instead of two)
- Less duplication (one inspection, one set of negotiations)
- Often quicker to produce an Award because communication is simpler
- Reduced chance of “back-and-forth” between two professionals
Potential drawbacks:
- Some neighbours prefer their own surveyor for peace of mind
- If trust is low, one surveyor may not feel acceptable to both parties
- Complex/high-risk work may warrant extra scrutiny through separate appointments
What are “Two Surveyors”?
With two surveyors, each owner appoints their own. The two surveyors then act under the Act and work together to agree the terms of the Party Wall Award. If they cannot agree on a point, a Third Surveyor can be called upon to decide that issue.
Best suited to:
- Higher-risk works (basements, underpinning, major structural changes)
- Multiple adjoining owners (e.g., flats) where viewpoints differ
- More complex construction methods or access needs
- Situations where neighbour relations are strained or communication is difficult
Typical advantages:
- Each owner feels independently represented (even though surveyors must still be impartial)
- Often provides greater confidence for nervous neighbours
- Helpful where there are technical disagreements that need robust scrutiny
- The Third Surveyor mechanism can resolve deadlock without going straight to court
Potential drawbacks:
- Higher cost (you may be responsible for reasonable fees of both surveyors in many cases)
- More time (coordination and negotiation between two surveyors can take longer)
- Potential for extended correspondence, especially where positions harden
Key differences at a glance
Cost
- Agreed Surveyor: usually cheaper overall
- Two Surveyors: typically more expensive due to duplicate time and communication
Speed
- Agreed Surveyor: often faster for straightforward matters
- Two Surveyors: can take longer, especially if negotiations are detailed
Complexity handling
- Agreed Surveyor: suitable for many routine domestic projects
- Two Surveyors: often better where works are complex, high risk, or contentious
Neighbour confidence
- Agreed Surveyor: works well when trust is reasonable
- Two Surveyors: can reassure neighbours who want “their own” professional involved
Which option is right for your project?
As a rule of thumb:
- If your project is a standard extension or loft conversion and your neighbour is fairly cooperative, an Agreed Surveyor is often the most efficient route.
- If your project involves underpinning, basements, significant excavation, complex steelwork, or there’s already tension, two surveyors may be the safer and smoother option in the long run.
A good party wall surveyor will talk you through both options and recommend the most proportionate approach based on risk—not just default to the most expensive route.
Need help choosing the right route (and avoiding unnecessary fees)?
Email mail@howorth.uk or call 07794 400 212 with a brief outline of your works (extension/loft/basement), your property type (terrace/semi/flat), and where you are in the process (notice served/response received). We’ll advise on whether an Agreed Surveyor is realistic, or whether two surveyors is the better choice for your situation.