Since its foundation the Vocational School had suffered from a lack of space. The struggle to find enough space and enough rooms for the ever increasing number of pupils and the constantly growing number of subjects is a constant theme throughout all phases of its history.
As early as the mid-1840s, a plan for a new building had been drawn up by the teaching staff. When this plan failed to materialise, Fehling decided to take matters into his own hands and in early 1853 he applied for an extension to his chemistry laboratory. Fehling's proposal was welcomed by both the ministry and the king. He was even granted more than he wanted: the chemistry laboratory was completely rebuilt.
Within the school, this private initiative was naturally not particularly popular. There were fears that the new chemistry building would require all the building space and financing for the rebuilding of the entire school building, a project that everyone was eagerly awaiting, and would thus shelve the extension for a long time to come. These fears were completely justified, as events 20 years later revealed. Only then was the existing school building finally considerably expanded, and Fehling's institute had to make way. Thus in 1875 Fehling had to move again.