The reduced rate of VAT can apply to the fitting of “energy saving materials” (in this case insulation) into residential properties. The taxpayer supplies roof panels for conservatories (which seem to be an addition freezer or barbeque to the house depending on the time of year). At the First and Upper Tier the Tribunals ruled that the supply was effectively a new roof not insulation. As such the reduced rate did not apply. At the Court of Appeal they have lost again.
Source Richard Luckin