What happens when two party wall surveyors can’t agree?
This is where a third surveyor party wall act mechanism comes into play. Think of it as someone brought in to break a deadlock. They don’t take over the entire case but deals with specific point the two surveyors can’t resolve.
If you’re a building owner or adjoining owner and find yourself in this situation, here’s what happens next and what a third surveyor’s decision means for you.
What Is a Third Surveyor and When Are They Appointed?
A third surveyor is an independent surveyor who steps in when the two appointed party wall surveyors have reached an impasse. They don’t manage the project or deal with the main party wall process but only becomes involved when there’s a disagreement on a particular matter.
For example, the two appointed party wall surveyors cannot agree on the cost of the remedial work for damage to a neighbouring property — a scenario we cover in more detail in my neighbour has caused party wall damage. The disputed point can be referred to the third surveyor.
The Trigger: When Two Surveyors Can’t Agree
Most surveyors settle their differences directly and rarely reach this stage. If they come across a genuine disagreement that they can’t resolve themselves, the disputed point will be referred to the third surveyor.
Why the Act Built in a Third Surveyor From the Start
Disagreements happen even between experienced professionals. The Party Wall etc. Act 1996 addresses that by requiring the selection of a third surveyor at the beginning of the process. They’re the fallback option if the two appointed surveyors reach a deadlock. It’s possible that the third surveyor is never called upon if everything goes smoothly.
How a Third Surveyor Is Selected
Selecting a third surveyor happens early, and the process is more structured than most people expect.
Selection by the Two Appointed Surveyors
Once a building owner’s surveyor and an adjoining owner’s surveyor are both appointed — whether as an agreed surveyor or two separate surveyors — agreeing on a third surveyor becomes their first joint task, well before any dispute has actually arisen. Each surveyor typically proposes a name from their own professional network, and the two then agree on one candidate together. The chosen individual is named directly within the initial appointment paperwork, ready to step in if needed later.
What Happens if Surveyors Can’t Agree on a Third
Occasionally the two surveyors cannot settle on a mutually acceptable third surveyor between themselves. In that situation, either surveyor can request that the president of the Royal Institution of Chartered Surveyors, or a body nominated under the Act, select and appoint someone instead. This fallback exists specifically so the process never stalls simply because two professionals cannot settle on a name.
Qualifications and Experience Expected
There’s no statutory qualification requirement written into the Act itself for a third surveyor, in the same way there isn’t for either appointed surveyor. In practice, the two surveyors nearly always choose someone senior and experienced in party wall matters specifically, often a practitioner both already respect professionally. Choosing someone genuinely independent from both original appointments matters more than any formal credential.
What the Third Surveyor Actually Does
The third surveyor’s role only makes sense alongside the two surveyors already working on a project, since their powers are narrower and more specific by design. Where the building owner’s and adjoining owner’s surveyors handle the whole party wall process from notice to award, the third surveyor deals only with the single point referred to them. The table below sets out how the three roles differ.
| Aspect | Building Owner’s Surveyor | Adjoining Owner’s Surveyor | Third Surveyor |
|---|---|---|---|
| Appointed by | Building owner | Adjoining owner | Both surveyors jointly, at the outset |
| Scope of involvement | Entire party wall process | Entire party wall process | Only the specific point referred to them |
| When they act | From notice through to award | From notice through to award | Only if the other two surveyors disagree |
| Decision-making power | Negotiates and agrees the award jointly | Negotiates and agrees the award jointly | Issues a binding determination alone |
Making a Binding Determination (Award)
A third surveyor’s determination becomes part of the overall party wall award the moment it’s issued. It addresses only the specific point referred to them, nothing wider.
- Covers the single disputed matter, not the entire project
- Carries the same legal weight as the rest of the award
- Must be followed by both the building owner and the adjoining owner
- Leaves the two original surveyors in place for everything else
Timeframes for a Third Surveyor Decision
There’s no fixed statutory deadline for a third surveyor to reach a determination, though most resolve the referred point within a matter of weeks rather than months. Simple disagreements, such as a dispute over a schedule of condition detail, often get settled faster than technical disputes involving structural calculations. Either surveyor can press for a reasonable timeframe once the referral has been made.
Who Pays for the Third Surveyor and Can Their Decision Be Challenged?
The cost and appeal questions people ask about a third surveyor usually come down to three things.
- Fee allocation: the surveyor or surveyors determine what’s reasonable, and the building owner typically covers the third surveyor’s fee alongside both appointed surveyors’ costs — see our detailed guide on how surveyors calculate fees under the Act.
- The appeal window: either party can challenge a third surveyor’s determination through the county court, but only within fourteen days of it being served.
- How rare referrals actually are: most two-surveyor appointments never need a third surveyor involved at all, since the vast majority of disagreements get resolved directly between the two appointed professionals.
Facing a Party Wall Disagreement? Get Expert Surveying Support
If two appointed surveyors have reached a genuine impasse on your project, or you’re unsure whether a third surveyor referral is even necessary, our RICS-certified team at Party Wall Resolution can review the disagreement and advise on the fastest way through it. Get in touch for a free consultation.
Frequently Asked Questions
What Triggers a Third Surveyor Being Appointed?
A genuine disagreement between the two appointed surveyors on a specific point within the award triggers it, and nothing else does. Most party wall matters never reach this stage, since experienced surveyors typically resolve differences through direct negotiation. When they can’t agree on something like the extent of protective works or a disputed damage claim, either surveyor refers that specific point to the third surveyor named at the outset, who then issues a binding determination on it alone.
Who Chooses the Third Surveyor?
The two surveyors already appointed by the building owner and the adjoining owner choose the third surveyor together, usually right at the start of the process. They agree on a name from their combined professional networks and record it in the initial appointment paperwork before any dispute has even arisen. If they can’t agree between themselves, either surveyor can ask the president of the Royal Institution of Chartered Surveyors to appoint someone instead.
Can You Refuse a Third Surveyor’s Decision?
No, a third surveyor’s determination is legally binding on both the building owner and the adjoining owner once it’s issued. Refusing to comply doesn’t set it aside; it simply risks the other party enforcing it through the county court. The only real route to challenge it is a formal appeal within the statutory window, rather than simply ignoring the outcome.
Is a Third Surveyor’s Award Final?
Broadly yes, though it can be appealed to the county court within fourteen days of being served. Outside that window, the determination stands and both parties are expected to comply with it as part of the wider party wall award. Appeals on the merits rarely succeed unless there’s a clear procedural error or the surveyor exceeded their authority, so most determinations do end up being the final word on the point referred.
How Much Does a Third Surveyor Cost?
There’s no fixed fee scale, since the Act leaves surveyor costs to be assessed as reasonable case by case. The building owner typically covers the third surveyor’s fee alongside the costs of both appointed surveyors, following the same general cost rule that applies to the rest of the process. Fees vary depending on how technical the referred point is and how much investigation the determination requires.
How Long Does a Third Surveyor Determination Take?
There’s no statutory deadline, so timing depends on the complexity of the specific point referred. Simple disagreements, such as a factual dispute over a schedule of condition, often get resolved within a few weeks. More technical matters involving structural calculations or engineering input can take longer, particularly if the third surveyor needs to commission their own assessment before deciding.
Does Every Party Wall Dispute Involve a Third Surveyor?
No, and in practice most don’t. The two appointed surveyors handle the overwhelming majority of party wall matters directly, negotiating and agreeing the award between themselves without ever needing to refer anything onward. A third surveyor only becomes involved on the specific projects where a genuine, unresolved disagreement arises between the two, which remains the exception rather than the norm.
Can I Choose My Own Third Surveyor as a Homeowner?
Not directly. The third surveyor is chosen jointly by the two appointed surveyors, not by the building owner or the adjoining owner individually. You can discuss preferences with your own appointed surveyor, and their professional judgement about who’s suitably experienced and genuinely independent carries real weight in that conversation, but the final choice sits with the two surveyors rather than either homeowner.