An online questionnaire has been published that asks residents whether they would prefer a 4.5m (14.7ft), 11m (36ft) or 32m (105ft) mural and suggests potential themes, such as poppies, service personnel, and wildlife.
Martin O’Connor, chair of the arts festival, which is leading the project, said: “The festival has been featuring large boards around the town for many years now.
“On the side of this building is a big, rather bland space, which has the potential to make a big impact on the town.
“We’ve had a few ideas linked to the war memorial and the fact Ashby is at the centre of the National Forest, but we want to open it to the public as it’s part of their town.
“We are proud of our culture and it would be great to have another focal point in the town.”
The consultation ends on 26 January.
Earlier this week, the town council confirmed it was considering making a bid to be named the UK’s first-ever Town of Culture.