A council has apologised after miscalculating the number of places needed for pupils at a new school.
Dargavel Primary in Bishopton, Renfrewshire, opened in January this year with a capacity of 548.
But it is now thought there will be an eventual peak of about 1,100 primary school age pupils as Dargavel village grows over the next decade.
Renfrewshire Council will now put up modular classrooms from next year to meet demand at a cost of about £2m.
Dargavel Primary currently has 463 pupils but after a higher than expected number of pupils started this year a review of the projected school roll was ordered.
The new forecast suggests the register could rise to about 600 next August and to between 685 and 705 in 2024.
