This is probably a silly question but I have been looking at a few buttercream recipes that call for whipping cream. May I presume that the cake would then have to be refrigerated?

Thanks in advance!

No, you don't need to refrigerate a cake iced in a buttercream made of powdered sugar, shortening/butter, and whipping cream--unless the filling in the cake needs refrigeration. The sugar and fat in the cream acts as a preservative and it's safe at room temp for a day or two.

I use this icing all of the time and have never had an issue with it.

HTH
Rae