The Act does not require a surveyor at the start and does require one at the point of dispute, which is why the answer changes halfway through a job. A building owner may write and serve their own notices, and many do. What a building owner cannot do is make an award, because an award has effect only when it is made by surveyors appointed under section 10. Between those two facts sits almost every version of this question.
What a party wall surveyor actually does
Once appointed, they act under the Act rather than for whoever pays them, which surprises people. They establish what work is proposed, agree with the other surveyor how it may be done, record the adjoining owner's property in a schedule of condition, and publish an award setting out the works, the conditions, access, making good and the fees. If damage happens later they determine it. They do not design the building, obtain planning permission, or take sides, and a surveyor who behaves as an advocate for the person paying is doing the job wrong.
When one agreed surveyor is enough
Where both owners are content, they may concur in appointing a single party wall agreed surveyor who acts for both. That is cheaper and faster than two, and on a straightforward loft conversion with a cooperative neighbour it is usually the sensible route. The alternative is one surveyor each, who then select a third to resolve anything the two cannot settle. Appointments are in writing and cannot be withdrawn once made, which is worth knowing before you make one.
Whether a party wall agreement without surveyor is possible
Only in one situation: the neighbour consents in writing to the notice. Then there is no dispute, no appointment and no award, and the job proceeds with no surveyor involved at all. It is still worth agreeing a schedule of condition between you, with photographs and a date, because that is the document that answers a damage claim later. What you cannot do is manufacture an award between yourselves once a dispute has been deemed to arise.
Questions people ask about do i need a party wall surveyor
Does Abutly find me a surveyor?
No. This site sells no listing, rates nobody and passes no enquiry to a surveyor or a builder. It counts the dates, sizes the documents and keeps them; finding a surveyor is your own search.
Who pays for the adjoining owner's surveyor?
The building owner normally bears the reasonable costs of making and obtaining the award, which is why a dissent is the expensive fork and a written consent is the cheap one.
Can I appoint my own builder or architect?
The appointee must not be a party to the dispute, and in practice must be competent to act under the Act. Appointing somebody with a commercial interest in the work is asking for the award to be challenged.