Most tax points fall within either the usual ‘Basic’ or ‘Actual’ categories. VAT Act 1994, s6 provides for these.
But VAT being what it is, there are numerous exceptions. And one covers services in the construction sector. This was highlighted in a case back in 2004. Cross Levels Developments Ltd considered a VAT planning arrangement where a college established a captive construction company to carry out certain works. The scheme fell foul of the provisions of VAT Regulation 93. This creates a tax point in relation to services performed where no invoice is issued, and no payment made, at the time the works are completed. HMRC Notice 708, chapter 24 explains the rule.
You can read the decision here: http://www.bailii.org/uk/cases/UKVAT/2004/V18689.html