Council tax band revaluation -when are improvements counted from?

Saltfish

We're buying a new house, already in a band which is going to hurt us! Knowing that the council like to revalue bands after a sale, does anyone know the answer to the following:

The house was extended in 1992.
Valuations are based on 1991 value, but came into force in April 1993.
If we can prove 1992 date of extension (we currently only have evidence of planning app and building plans approval 1991) , can the council use this to justify 'improvement' for a band revaluation?

In other words, from what date are home improvements/extensions counted for the purpose of upping c-tax bands? any answers greatly appreciated.

I know there are other factors which the council can consider, but on this specific issue I cannot find a clear answer from Mr Google.

Jeremy535897

You could ask the vendor, but as the valuation is based on what the property would have sold for on 1 April 1991 (in England), it's hard to see how the extension could already be included in the value (one would have thought that if it was, by error, the vendor would have appealed back in 1993).

lincroft1710

Jeremy's answer is not quite correct.


CT came into force on 1 April 1993 and bands reflected the physical state of a dwelling at that date, but using 1 April 1991 as the antecedent valuation date. Only the VOA would know if the 1992 extension had been picked up and was reflected in the current band. If the extension wasn't picked up or was not finished on 1 April 1993, then there is a possibility of a band increase. 

p00hsticks

Aren't such properties flagged with 'improvement indicators' on the council tax register to show that there is a possible potential rebanding to take place on the next sale as the property has been extended ?

Or could the fact that in this case the improvement took place between the valuation date and Council tax actualy coming in to force mean that it may have falled throguh the cracks and not been marked as such ?