CA 3 May 1989. Appeal against a judgement in favour of (D) against the landlord (Y) in respect of his refusal to agree to a loft conversion on the grounds that Y had unreasonably withheld consent and license to the alterations and therefore D was entitled to proceed. The lease was for a first floor flat including the roof and roof space and included a repairing covenant. It also contained a statement to the effect that any additional building needed the landlords consent . D claimed that the alterations constituted an improvement but not additional building and she could therefore rely on Landlord and Tenant Act 1927 s19 to make the requirement of consent subject to a provision that consent should not be unreasonably withheld. The appeal was dismissed on the grounds that as the loft conversion did not extend into airspace running alongside the property it did not constitute additional building.