No apportionment shall be made for new construction which when added to the area of adequate school construction existing in the applicant school district at the time of application, will provide a total area of school building construction per pupil of the estimated enrollment in excess of that computed under the following schedule:

The maximum total building areas per pupil allowed to applicants having schools with smaller estimated enrollments than shown in the above schedule shall be determined by the State Department of Education, and shall be building areas to provide comparable facilities to those enumerated above, and shall be the least building area required to house adequately the estimated enrollment and the normal instructional and other services.

No estimate of enrollment made by an applicant for the purpose of justifying an apportionment shall be made for a longer time than the second fiscal year beyond the fiscal year in which an application is made, and in no case shall be given effect unless approved by the State Department of Education.