I am working on a new home and need some height so I can have the proper slope from a toilet closet flange to the leeching field. All of the stadard closet flanges and elbows drop a minimum of two inches below the subfloor. I would like a closet flange and elbow that hug the underside of the subfloor, so that I can maximize my drop and slope of the drain pipe. Does anyone make a short necked closet flange and elbow. Basically I am looking for the drop to be the thickness of the subfloor.