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HMRC internal manual

VAT Construction

Zero-rating the construction of buildings: is a building being constructed: what the term ‘existing building’ means

The law identifies ‘an existing building’ by setting conditions to decide when an existing building ceases to exist. These conditions are contained in the Value Added Tax Act 1994, Schedule 8, Group 5, Note 18.

They are:

An existing building remains when neither of the tests is passed.