A swanky new apartment could be built in the converted basement of a city centre office block.
The plan has raised questions over noise levels and the future of Norwich's economy.
St Peter's House in Cattle Market Street has previously been converted from commercial use into 53 apartments.
And there are now further proposals to convert a basement storage area into a one-bedroom home at the site.
A comment has been submitted to the city council planning portal by someone currently living in the building questioning whether this will cause noise disturbance to existing tenants and homeowners.
Planning papers submitted by Haskins Designs states that only minor changes would be required to the external elevations if the plans are approved.
The agent also states the proposals would provide a sustainable development of the building and "provide much-needed residential accommodation".
Anthony Breach, a planning analyst at the Centre for Cities think tank, said conversion of office space into new homes is beginning to wind down after the government enforced development rights in 2013 which enabled such change of use to take place.
The analyst believes this process ensured derelict buildings and brownfield sites could be repurposed.
But he questions the extent of converting commercial space into accommodation within Norwich city centre.
Mr Breach said: "We have to be careful about commercial conversions into residential in the city centre. We think of suburbs broadly being where people live and the city centre is broadly where people go to work.
"If there is too much commercial space lost in the city centre then it does damage the wider city economy."
He pointed out the city council could apply for an article four direction to prevent the commercial space being converted.
Mr Breach also highlighted a surge in single-class conversions in which empty retail units can be converted into a gym or another shop, for example.
Planning permission was first granted to convert St Peter's House into two homes and an internal private swimming pool in October 2014.
A change of use from offices to 53 apartments was then given the green light in August 2018.
Haskins Designs has been contacted for comment.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here