The reduced rate applied only to "renovation or alteration of a single dwelling which has been empty for three years or more, conversion of a dwelling, or changing the number of dwellings (eg from two houses into one), conversion of a dwelling into a multiple occupation dwelling (ie flats), conversion of a dwelling or multiple occupation dwelling to a building intended for 'relevant residential purposes' ". [source: http://www.buildingconservation.com/articles/vat/v at.htm
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