I own a 115 yo house. The front entryway is 35 sq ft (including closet) and has a 3" HVAC line to a floor register. I am now installing ceramic tile. I can't run the HVAC to the wall, so my options are to set a floor vent or just forget about it, tile over it and disconnect the duct. Because it is an old house with a dbl joist on that side, cutting out the subfloor isn't all that easy.
Not enough info to make a good suggestion.Is the enterance way open to the rest of the house?what area of the world do you live in.Does the enterance way get very cold or very hot?I know 4 1/2 x 7 or so isn't very large but a 3" feed is almost nothing too so its probably sized ok.Why can't you have a HD grille in the hallway?