Concerns have been raised over plans to build 69 flats on the site of the former Kingsland Road fire station, which was bought by the government for £16m to house a new primary “free school”.

Hackney New School (HNS) has held an open day consultation on its plans for the station in Haggerston, which was one of 10 that Mayor of London Boris Johnson shut down two years ago in cost-cutting plans, despite massive community opposition.

Youngsters at the primary school are currently being taught in temporary premises inside its parent school, Hackney New School, a secondary school just opposite in Downham Road.

HNS wants to build 69 flats, along with retail floor space in a tower block up to 11 storeys high alongside a primary school with a roof garden for 350 children.

At a pre-planning meeting last week, councillors expressed concern about natural light in the courtyard, and its size which “doesn’t look like there’s much room for just charging around”, as well as the size of the school building – which they were told conforms to or exceeds the Education Planning Authority’s space standards.

Cllr Rebecca Rennison said: “My concern is making sure that the school comes first, and the school space is not overlooked and the children are not aware there is a large residential development on their school site.

“I realise it’s difficult how we fund schools and we get residential to fund schools, but here you have 11 balconies looking down onto the school yard.”

Founder Philippa De’ath told the committee they had learned from the secondary school build. “I hate to use compromise but space was a limitation,” she said. “We have more outdoor space in this project, and that was one of the reasons we chose to disaggregate the school from the residential block, because then we could put the roof garden on, which we couldn’t have done otherwise.”

HNS hopes to open the primary school by September 2017.