I am Sadadcharam Easwaran, and after 5+ years in party wall work I am often asked the same question. Should both neighbours share one surveyor?
The single surveyor option, known as the agreed surveyor route, is excellent in the right situation. It is also wrong in others. This post explains, from experience, when it works and when it does not.
The Agreed Surveyor Route: How It Works
Under the Act, both owners can appoint one impartial surveyor. That single Agreed Surveyor acts fairly for both sides.
The agreed surveyor route is the simplest version of the process. One professional, one set of fees, and one document at the end.
It is not a soft option, though. The Agreed Surveyor still owes a duty to both owners, not to whoever appointed them.
Here is how I weigh the two routes:
| Choose an Agreed Surveyor when | Choose two surveyors when |
|---|---|
| Neighbours trust each other | Trust is low or strained |
| The works are straightforward | The works are complex or deep |
| Both want a lower cost | The neighbour wants own representation |
| A quick timeline matters | Reassurance matters more than speed |
When the Agreed Surveyor Route Works Best
In my experience, the agreed surveyor route works best when neighbours trust each other. A friendly street, a simple project, and two reasonable owners are the ideal.
It also suits straightforward works, like a standard loft or a modest extension. Where the issues are clear, one surveyor settles them quickly.
For most domestic jobs in London, this is the route I recommend. It is faster, cheaper, and keeps relationships intact.
When Two Surveyors Are the Right Call
Sometimes two surveyors are genuinely better. If an Adjoining Owner feels uneasy, having their own surveyor brings peace of mind.
Two surveyors also suit complex or high-value works, like deep basements. Each owner then has someone focused solely on their interests.
The two surveyors route costs more and takes a little longer. But where trust is thin, that extra reassurance is worth it.
I never talk a worried neighbour out of their own surveyor. Their comfort is part of getting the job done well.
Two Cases That Show the Difference
Two recent jobs sum it up. On a simple loft in a friendly terrace, one Agreed Surveyor settled everything in a fortnight.
On a deep basement beside an anxious elderly couple, two surveyors were far better. They wanted their own person, and that reassurance kept the peace.
Same Act, same office, very different routes. The people and the project decided it, not a fixed rule.
Neither client paid a penny more than they needed to, because the route genuinely fitted the job.
What It Means for the Building Owner
As the Building Owner, you usually prefer a single surveyor, and for good reason. You normally pay the fees either way.
A single surveyor keeps the Building Owner’s costs down and the timeline short. That is a real advantage when you are funding the project.
But a Building Owner should never force it on a reluctant neighbour. Pushing the choice often backfires and slows everything down.
The saving is real, but goodwill is worth more. A neighbour who feels heard rarely causes a delay.
What the Adjoining Owner Needs
The agreed surveyor route only works if the Adjoining Owner truly consents to it. They must be comfortable sharing a surveyor.
An Adjoining Owner has every right to appoint their own surveyor instead. As an Adjoining Owner Surveyor, I represent them alone.
So I always check that the Adjoining Owner understands both options. A pressured agreement is not a real one, and it rarely lasts.
The Question I Always Ask the Neighbour
Before recommending a single surveyor, I ask the Adjoining Owner one thing. Do you feel comfortable with me acting for both of you?
If there is any hesitation, I explain their right to their own surveyor. An honest answer there saves a great deal of trouble later.
That comfort is the whole foundation. Get it wrong, and a cheaper choice quietly becomes the slower one.
How the Agreed Surveyor Reaches the Party Wall Award
Whichever route you choose, the goal is the same: a fair Party Wall Award. The Agreed Surveyor prepares this Party Wall Award under section 10 of the Act.
A single surveyor drafts one Party Wall Award covering both homes. With two surveyors, they agree it together, which takes a little more time.
The Party Wall Award is identical in legal force either way. The route changes the journey, not the destination.
The Honest Downsides
To be balanced, this route is not perfect. A nervous neighbour may later feel they had no champion of their own.
If a serious dispute erupts mid-project, a single surveyor can feel stretched. In those rare cases, two surveyors would have served better.
I am upfront about this with every client. The right route depends on the people, not just the project.
I would rather flag the risk at the start than have a client surprised by it midway. Honesty early is part of the service.
How I Decide
When a client asks, I weigh three things: the relationship, the complexity, and the neighbour’s comfort. Those usually decide it for me.
If all three point the same way, the choice is easy. When they do not, I say so plainly, even if it means a higher fee for my client.
Our guide comparing the two routes sets out the trade-offs, and the official government booklet covers the legal basis.
A Final Word
After two decades, my honest view is that the agreed surveyor route is right more often than not. But not always, and that distinction matters.
Choose it when there is trust and simplicity. Choose two surveyors when there is doubt. Either way, both homes end up properly protected.
Sadadcharam Easwaran, ICE and CABE chartered surveyor, Lenio Party Wall Surveyors.
Frequently Asked Questions
Is the agreed surveyor route always best?
No. The agreed surveyor route is ideal when neighbours trust each other and the works are simple. For complex jobs, or where trust is low, two surveyors can serve both sides better.
What is an agreed surveyor?
It is a single, impartial surveyor appointed by both owners. They act fairly for both sides and prepare the Party Wall Award, rather than representing one owner alone.
Can I refuse an agreed surveyor?
Yes. An Adjoining Owner can always appoint their own surveyor instead. No one can force you to share a single surveyor if you would rather have your own.
Is an agreed surveyor impartial?
Yes. Despite the name, an Agreed Surveyor owes a duty to both owners, not to whoever pays. Their job is to act reasonably for both homes.
Does an agreed surveyor cost less than two surveyors?
Usually, yes. One surveyor means one set of fees, so the total is lower. The Building Owner normally pays either way.
Who appoints the agreed surveyor?
Both owners jointly agree on the same person. If they cannot agree on one name, the process moves to a surveyor each instead.
Can we switch to two surveyors later?
In practice it is best decided early. If a real conflict appears, an Adjoining Owner can still appoint their own surveyor, but starting again costs time.