The $17-million redevelopment will upgrade the town hall and Horsham Regional Art Gallery, add a 531-seat performing arts centre and connect Wilson and Pynsent streets with a public walkway.

Art gallery director Adam Harding led three tours of the site, which showed more than 70 people the major changes.

He said the town hall's front facade, stage, floor and balcony seating would be kept in the redevelopment.

"The real big change will be the heating and cooling, which we haven't had before," he said.

"The hall will be the same as it has always been - a big empty space.

"If you want to have big whiz-bang performances, we will have the space next to it in the performing arts centre."

Horsham mayor David Grimble said council would focus on the cost of the project before awarding a tender in July with construction to begin in August.

He said council was completing a bill of quantities, which would itemise all the project's expenses.

"It is a case of wait and see as to whether the tenders will come in under budget because the project cost is an estimation," he said.

"Cost escalation is something we really need to track but the bill of quantities will give us a clear picture.

"It is a very big commitment by council and there is a lot of excitement."

Horsham woman Jenny Sonego said she was impressed by the amount of work council had done on the project.

"We need to trust the people because they have put in a lot of work," she said.

"We should appreciate that and get on with it so we can enjoy it.

"I think it is great that the town hall is being kept because I have danced around here for a long time."

Murtoa woman Anna Hawkins said she was concerned the public walkway connecting Pysent and Wilson streets was too narrow to provide for the hundreds of people using the centre during events.

"I want to see something done with the town hall and I support the project but I am concerned about the spaces," she said.

"My concerns are that you will have a lot of people spilling out of the town hall and performing arts centre, and there is not much space for them.

"It is definitely not the space we have now."