The Valuation Officer has a statutory duty to maintain a correct rating list. When he/she becomes aware that an internal physical refurbishment of a property has increased its rateable value, under the statutory definition, he/she is obliged to alter the current rating list accordingly. The rateable value must have regard to the market conditions at the antecedent valuation date (1 April 2003 for the current rating lists), and will take effect from the completion of the works.
A refurbishment which addresses disrepair may not warrant an increase in the rateable value since the statutory definition already assumes a reasonable state of repair.