Converting downdraft to an overhead vent

Question:  I would like your advice on converting an existing downdraft range hood to an overhead hood. Is it possible to use the existing vent line running through the floor (slab) then make a connection to new ductwork going up the wall to the overhead? Have you ever heard of this being done? Any links would be appreciated. Thank you for your response. Leonard

Jake's Answer:  Leonard, yes, you can convert your venting.  It seems you most likely will have to do some floor demo to redirect your duct up through the wall, if the existing comes up through the bottom of the cabinet.  Assuming that the existing vent line is a 3 x10 or 3 x 12 this should fit in your wall cavity. A couple of things to consider is the duct size requirement of your new range hood and the number of elbows you will have in the line.  Most venting situations have a limit on how many feet the line can run until it is discharged outside.  This information is usually included in the hood specifications.  I do not know of any links, try Googling it.  Good luck.