The combinations of layouts for utilizing the ROOF DRAIN DE-ICING SYSTEM Components is virtually limitless.

One of the more common layouts is the combination of a primary drain (here with 6RDDJ22 in place) coupled with an overflow drain (to photo left) on a flat roof .  This pair of drains may be:

• near the  center of the roof, 
• within a few feet of the perimeter parapet wall, or
• one of many pair scattered about to handle the water removal of a very large roof.

Another common combination is to have a standard roof drain paired with a canale or scupper acting as the overflow drain.

It is common to have the standard roof drain water pass through piping which will remain within the heated space above the interior ceiling.

The scupper/canale collects water as it flows through an opening at roof grade in the parapet wall. The water is then directed down to earth grade through a downspout (scupper type) or by free fall (canale type).