First Division 10 July 1992. A housing association constructed houses and let them to tenants for terms not exceeding 21 years. After two years tenants acquired the right to buy and the association drew up contracts for the sale. The association was therefore granting a major interest in the dwelling within the meaning of Value Added Tax Act 1983 s48(1). In November 1989 the commissioners decided that the association was not entitled to input credit on the grant of the major interest because by the time of the grant the association had ceased to be `a person constructing a building` within the Item 1a, Group 8, Schedule 5 of the 1983 Act. The Triubunal allowed the association`s appeal on the basis that ` a person constructing a building` was an ambiguous term and ought to be interpreted as `a person who has constructed a building` so that the original builder could recover input tax at any time until he disposed of a major interest in the property. It was held that `a person construc