Shellharbour City Council general manager Michael Willis has denied claims the Shellharbour City Hub plan is "lavish".
While formal plans for the $57-million project are expected to be lodged next month, aspects of the design detailed in the business case of the hub angered members of the Stop the Hub community group.
Shellharbour accountant Mark Jones last week blasted the size of office space for the general manager and mayor for being excessive and said the addition of large yoga and fitness areas for staff was "lavish".
But in a letter to the Mercury, Mr Willis said while yoga and fitness areas had been included in the original design brief, they had been reduced to one recreational space in the lower level basement area following staff consultation.
"While it's important that we promote health and well-being for staff, the area currently proposed could hardly be described as 'lavish'."
Mr Willis also said the original design of the offices had been reviewed to ensure it delivered the "most efficient outcome".
"It must be recognised that we are planning a building to cater for the needs of the city whose population will grow to more than 79,000 in 2031 - which is higher than the current population of Coffs Harbour.
"We need to ensure that the facilities in the city hub meet the community's requirements - and the requirements of a sizeable regional city
- well into the future, and not just through the lens of the present."