The Block winners Dea and Darren Jolly face a huge fine and will be required to rebuild the heritage-listed Melbourne home they controversially demolished without a permit.

Last month Fairfax Media revealed the reality-TV pair had knocked down and levelled an early-20th-century home in East Kew after obtaining only a partial demolition permit.

A furious local council is now demanding they rebuild the heritage-listed home's facade as well as instructing council lawyers to take the Jollys to court over a planning permit breach.

But the Jollys have hit back, saying the house was "just a bloody mess" and they had no choice but to demolish. They say they were always planning to rebuild the house.