Lumber and Siding - Attaching vertical aluminum down-spout to vertical vinyl siding? (with picture)

My old siding was horizontal particle board stuff and I'm replacing it with vertical vinyl. On the old siding, two clamps were fashioned from a 2" wide loop of aluminium, and simply screwed to the siding and the down-spout. With the new vinyl, I'm worried about expansion/contraction because the attachment points are both on the same piece. Have a look at the picture, I've indicated the layout of the down-spout and where it was previously attached. Rain is predicted for the next 4 days so I've got to get it hooked up, at least temporarily, today! Any recommendations, thoughts or ideas of how I could attach to the new siding? I was hoping to just re-attach the old down-spout, but I guess I can shorten, extend or reroute if necessary.

P.S. If it helps, this is the north side so it receives no direct heating from the sun.

http://web.ncf.ca/fq719/siding/IMG_0961.JPG

I would go with one of the decorative straps, attach it in one place through the vinyl, chasing silicone with the screw, then attach the downspout on the sides with short screws. At least you will have only one infiltration point and with it siliconized, your exposure to moisture will be nil.

One strap, as Larry suggested, or two, in the locations that you are showing. Either way, do them like Larry said. Attach the strap with one screw through the vinyl, then install the downspout. Mine have been like that for about 10 years.

With the weight of ice that will be inside those downspouts this winter you definitely want two attachment points as you illustrated. For vinyl siding, all you usually need to do is drill a 3/8" hole (with a drill bit) through the siding to allow for expansion and contraction around the screw. Don't drill into the sheathing with the drill bit, since that is what your screw needs to bite into. Fill the hole with silicone as mentioned, screw your strap to the sheathing, putting silicone on the threads of the screw as you screw it in for good measure. (chasing with silicone, as Chandler put it). You can use the old aluminum loops or go with new straps.

XSleeper,

Good call on the ice issue. Where Chandler an I are, ice isn't an issue, so we never think of it. Ontario Canada -- certainly an issue.

Here is the resulting installation, with 2 clamps made of pieces of scrap aluminum from the old capping off the front window. We'll see how the vinyl reacts next summer when it gets a little hotter. Next summer I'll be regrading and landscaping around the house and I'm going to bury a pipe running from the house and emptying in the middle of the front yard. The downspout will empty directly into this pipe, doing away with the unsightly extender I'm currently using.

http://web.ncf.ca/fq719/siding/IMG_0974%20(2).JPG