Over the last few months, there have been a growing number of proposals for tall buildings in Dublin. The most recent was on the former Hickeys site, at Parkgate Street between Heuston Station and the entrance to Phoenix Park. The proposal by Chartered Land includes a 29-storey tower as part of a four-block development, containing in total 481 homes. The property developer Johnny Ronan, meanwhile, continues to battle planning authorities over his proposal to increase the site of the Salesforce Tower in Dublin. The spate of projects has some worrying about another bubble. One reason that we are seeing these…