Hi! I recently purchased a Regency U-39 natural gas as floor model from a local dealer that is going out of business. My question is do I need to use a vinyl siding stand off. It is a direct vent model. I am using DuraVent double wall piping. I got the black pipe that comes vertically off the stove and the black 90 degree elbow that goes out the wall. I purchased and will be using a DuraVent 46DVA-HU Direct vent horizontal termination. The installation instructions for the stove say that a wall thimble is only required for installations in Canada. I purchased and will be installing one anyway. It seems like the right thing to do. I also purchased a black thimble cover for the inside wall. The wall that I will be installing the exterior Horizontal Termination on is Vinyl sided. The instructions for the stove say that a vinyl siding stand off is optional. The wall I'm installing the termination on is highly visible and is located near an outside patio area. The termination by itself makes a reasonably aesthetic installation. The stand off however is large and bulky and not so much attractive. Can someone suggest whether or not I really need the stand off if I'm using the optional thimble. Thanks. Much. Ken