In simple terms a party wall sits astride a boundary to land belonging to several different owners and forms section of a building using one or both properties.
A wall which sits astride the boundary but does not form section of a building is a Party Fence Wall for the purposes of the Act.
The word Party Structure can be used in the Act. A floor structure separating flats is one example of a Party Structure.
When does the Party Wall Act apply?
The Act will apply when:
Various works are completed to an existing Party Wall or Party Structure
New buildings or structures are erected around or sat astride the boundary line
Excavations are completed around 6 metres of a structure on a neighbouring property which have the potential to undermine the foundations of that structure
So the Act applies to my works, what do I do now?
If the Act applies you may be obliged to serve a Party Wall Notice on your neighbour, setting out information on the works accessible and providing key information such as plans, proposed commencement dates etc. Regarding adjacent excavations you may want to provide specialist details of foundations.
You will be obliged to provide your neighbours between 1 and 2 months notice of commencement of work based on which section of the Act applies.

What goes on if my neighbour objects to my Party Wall Notice?
The Act gives you the right to complete various types of focus on or around the boundary line so provided your works are covered by the Act your neighbour's objection cannot stop you going ahead but means that you will be obliged to check out the Dispute procedure set out under Section 10 of the Act.
This requires one to appoint a Party Wall Surveyor to act in your stead. https://click4r.com/posts/g/16334663/ gets the right to appoint their own surveyor or they could agree in the appointment of an individual 'Agreed' surveyor. Where two surveyors are appointed they'll acknowledge the appointment of a third surveyor to adjudicate/referee where the two surveyors cannot agree.
The surveyor prepares the Agreement/Award which sets out the rights and obligations of both parties and includes a Schedule of Condition of the neighbouring property to record its condition before works start.
Exactly what is a Party Wall Agreement/Award?
Look at this website is the written document made by the surveyor detailing the rights and obligations of the owners. The contents are agreed by the survey and upon completion the Agreement is served on the owners.
This is usually a legally binding document which is often enforced by the County Court where necessary.
Evans Jones certainly are a team of Chartered Building Surveyors in Cheltenham, who've been dealing with the Party Wall Act since its inception in 1996. You can be dealt with by a specialist Party Wall Surveyor with connection with all aspects of the Act who can help you simply and clearly how best to meet your obligations beneath the Act.