Charter school leaders ripped Mayor de Blasio on Wednesday for delaying co-location requests despite ample room in city buildings.

“The city’s own data shows that there are 112 chronically underutilized buildings citywide, far more than enough to meet the demand from charter school families,” Families for Excellent Schools, a charter advocacy group, said in a statement.

But the Department of Education has repeatedly stated that vacancies and school enrollments are in constant flux — and that space is just one co-location consideration.