Atrium, which opened its doors in 1992 and its sister restaurant Blue, which opened four years later, were shut down by the Radfords last year.
Andrew Radford told BigHospitality the decision to close successful businesses hadn't been easy, but was essential to secure the family's future success in the industry.
"Their locations became slightly unfashionable and their rents went up considerably so in 2010 we decided to start looking for something else, but we realised that if we were to find the right place we'd need time to do it properly, we couldn't do it while running a restaurant," he said.
The couple finally opened Timberyard, a 60-cover restaurant and bar, on the site of a former warehouse and timber yard in the city's Lawson Street at the end of August with their sons Ben and Jo, who are head chef and bar manager respectively and daughter Abi.
The restaurant is currently open five days a week, from morning coffee through to dinner. Its menu uses ingredients sourced from local artisan producers and features a range of daily changing seasonal dishes such as pumpkin tart, honey, highland crowdie and venison haunch celeriac, barley, kale and hazelnuts alongside £10, £14, £18 and £22 set menus.
Radford said sustainability would be key to the restaurant's future with plans to grow herbs, fruit and vegetables in a patch of ground within the restaurant's courtyard and install an area to cure and smoke other produce.
So far, neither the career holiday nor the move to the new location has harmed trade with Radford reporting an average of 100 covers a day for dinner every day since opening and a series of glowing reviews from the city's restaurant critics.
He said: "With the children involved in the business we seem to have not only attracted our generation but their generation too so we're working on a number of levels. I think we're also at the right price point for many people. We've made it accessible so that they will come back regularly."