Will the buildings, ULB, seminar rooms and learning centers reopen?

Yes, buildings and learning centers will gradually reopen. You can find the current informations under https://www.tu-darmstadt.de/universitaet/aktuelles_meldungen/corona_vorsorge/informationen_fuer_alle_mitglieder_und_gaeste/index.de.jsp

A list of the learning centres of the departments can be found here. Please note that there may be separate rules for the use of the learning centres and inform yourself on the websites of the offering departments.