24 Pa. Stat. § 6-677.1
Whenever in second, third and fourth class school districts there is any construction of a building or buildings not otherwise exempt as a dwelling and such building is not included in the tax duplicate of the school district, the authority responsible for assessments in the city, borough, township or county shall, upon the request of the board of school directors, direct the assessor in the district to inspect and assess, subject to the right of appeal and adjustment provided by the act of Assembly under which assessments are made, all taxable property in the district to which major improvements have been made and to give notice of such change in the assessed valuation within ten days to the authority responsible for assessments, the school district and the property owner. Such property shall then be added to the duplicate, and shall be taxable for school purposes at the assessed valuation for that proportionate part of the fiscal year of the school district remaining after the property was improved. Any improvement made during the month shall be computed as having been made on the first of the next succeeding month. A certified copy of the additions or revisions to the duplicate shall be furnished monthly by the board of school directors to the tax collector for the district, and within ten days thereafter the tax collector shall notify the owner of the property of the taxes due the school district.
24 P.S. § 6-677.1