My house more than likely predates BS anything, but I am well aware that ceiling joists have a much smaller design load to support than floor joists. Professional advice is probably necessary, rather than all youse internet experts! :P
When was your house built? Some were built stronger than others. It depends what you plan on putting up there, and if you want to be able to walk/crawl around too. Get a structural engineer round if you want peace of mind.
My house more than likely predates BS anything, but I am well aware that ceiling joists have a much smaller design load to support than floor joists. Professional advice is probably necessary, rather than all youse internet experts! :P