Holly Willoughby and her TV producer husband Dan Baldwin want to build living space for an au pair at their riverside home in Barnes.

The couple submitted documents to Richmond Council seeking permission to convert their garage into living quarters for someone to help bring up their three children.

They bought the five-bedroom house in Barnes in late 2011 for £2.8 million, but property website Zoopla estimates it is now worth £5.5 million.

In the time they have lived there, the couple has sought permission to carry out work from the council 13 times – sometimes for minor changes including felling trees, but also more significant building work.

Two and a half years ago, they were given the go-ahead to excavate below the house to build a basement.

But at about the same time, their application to build a two-storey extension was rejected because of the plans’ “excessive” scale.

The couple appealed but a government inspector upheld the council’s decision.