When party wall matters move from friendly discussion to formal dispute, most projects run smoothly with either an Agreed Surveyor (one surveyor acting for both owners) or two appointed surveyors (one for each owner).
Occasionally, those two surveyors can’t agree on a point of principle or detail. That’s when the Third Surveyor steps in.
This guide explains how a Third Surveyor is selected, what they do, how they resolve disputes, and who pays their fees—in plain English.
How is a Third Surveyor selected?
Under Section 10 of the Party Wall etc. Act 1996, when each owner appoints their own surveyor, those two surveyors must jointly select a Third Surveyor at the start of their appointments.
- The Third Surveyor is not appointed by either owner and doesn’t get involved by default.
- Think of the role as a pre-agreed, independent referee—ready only if needed.
Good practice is to pick a Third Surveyor with strong technical competence (structural/temporary works literacy), proven statutory experience, and genuine impartiality. Their details are recorded by the party-appointed surveyors so they can be contacted swiftly if a referral becomes necessary.
What does a Third Surveyor actually do?
The Third Surveyor’s jurisdiction is narrow and targeted: they deal only with the matters the two surveyors (or either owner) formally refer to them. Typical referrals include:
- Method statements or means and manner of executing notifiable works.
- Access terms (scaffold, hoarding, times, protections).
- Design changes that affect risks to the Adjoining Owner.
- Allocation of costs or reasonableness of fees.
They do not re-open the entire case or rewrite an Award from scratch. They decide the specific points in dispute, then issue a Third Surveyor’s Award that is binding (subject to the usual 14-day county court appeal window).
How do they resolve the dispute?
Procedure is flexible but must be fair. Expect some or all of the following:
- Defined questions: The party surveyors (or an owner) set out the precise issues for decision.
- Written submissions: Each side explains its position with drawings, calcs and evidence.
- Right of reply: The other side responds—ensuring natural justice.
- Site/technical review (if required): The Third Surveyor may inspect, or consult an advising engineer if proportionate.
- Determination by Award: The decision addresses only the referred matters and may include directions on time/manner, protections, access, and costs.
A well-framed referral and concise evidence speed things up and help contain fees.
Who pays the Third Surveyor’s fees?
The Third Surveyor has discretion to award costs in their decision. In practice:
- If one party’s stance was unreasonable, costs often follow that outcome.
- Where both sides argued reasonably on a technical point, costs may be shared.
- The Third Surveyor can retain the Award until their fees are paid (standard practice).
Remember: Building Owners typically fund the Act process when the works are for their sole benefit, but costs can be apportioned if the facts justify it (e.g., defects/repairs, or unnecessary resistance). Either way, only reasonable, proportionate fees should be awarded.
Practical tips to avoid Third Surveyor referrals
- Nail the scope early: Clear drawings (especially for Section 6 excavations) and method statements reduce friction.
- Stay within the Act: Surveyors should confine decisions to statutory matters—not boundary lines or private easements.
- Use targeted questions: If a referral is unavoidable, agree the exact questions so the decision is swift and focused.
- Keep it proportionate: Evidence should be concise, relevant, and technical—avoid noise.
Simple Survey: cost-effective, calm, and compliant
Our fees are designed to keep projects moving without drama:
- Party Wall Notice service: £25 per adjoining ownership (multi-notice bundles discounted)
- Act administration as Agreed Surveyor (single surveyor): typically £300 fixed-fee (depends on complexity and number of notices/owners)
- Two-surveyor route (we act for the Building Owner): fixed-fee proposals from £325 for our side (we work to keep your neighbour’s surveyor’s hourly fees reasonable and contained)
From Notices to Awards—and, if needed, Third Surveyor strategy—we focus on clear paperwork, pragmatic solutions, and fair fees.
Ready for a straight answer on your dispute?
Email your plans and a brief summary to team@simplesurvey.co.uk and we’ll confirm what’s notifiable, the fastest compliant route to an Award, and whether a Third Surveyor is likely—or avoidable.
Simple Survey — the cleanest line from Notice to Award.