Supporting ducts horizontally seems pretty straight forward–just a loop of strapping underneath to support it. What about when the duct runs vertically? Do you use the same kind of strapping but attach it to the duct with screws, or is there more to it?
How to support vertical runs of round ducting
ductsexhaust-fanhvac
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New answer thanks to updated question.
Yes, the lip around the rim of the opening I'd call it a "ridge" but I dunno if that's right) on the boot is there to help ensure a firm connection. It's to keep the zip tie on the inner core from slipping free. This is necessary (the keeping the duct snug, not nessarily the tie) if your ducting is going to be pulling away from the boot due to gravitational stresses - such as when the boot is above the duct and the duct can be pulled down, such as along a wall or below a ceiling or floor. If your boot points down and the duct sits on a horizontal surface, you're good - no extra tension should happen.
Important note - neither mastic nor tape are intended to be structural - they don't serve to hold the ductwork in place, they serve to seal the ductwork so that there are no air leaks.
So the question really is - how do I properly secure my flexible ducting to the boot when there's no lip on the collar? Answer: Self-tapping screws.
Get yourself a box of those (the hardware aisle or the ductwork aisle). When you go to mount your ducting, pull the outer insulation back up away from the core, pull the core over the collar, and use TWO screws on opposite sides of the duct (180 degrees from each other - noon and 6'o clock (or 1 and 7, 3 and 9, you get the idea) to ensure that neither side of the duct can pull free.
Use the inner to snug up the connection (don't over tighten!), seal with mastic (I'd recommend tape though cause of the insulation layer...), slide the insulation up as far as it will go and snug it up with the outer zip.
If the cinder blocks are empty, a standard masonry drill bit in the 3/4 inch (19 mm) range plus a sawzall (which can be inexpensively rented, but you'll have to buy a blade).
Trace a duct end onto the blocks where you want the hole: it is best that the edges of the hole be at least an inch (3 cm) away from cinder block edges and mortar but can go through them.
Drill the 3/4 inch pilot hole inside but near the circle's line. Use care to get it square (perpendicular) all the way through and press lightly as it passes through the opposite face. (If you drill the hole right on the line, there will be an unsightly gap to deal with later.)
Place sawzall into the hole and—if you haven't used one before, practice by cutting toward the center of the circle—cutting slowly to avoid fracturing the brittle material. Until you get a feel for how much chipping it does, stay safely away from the line—an inch should be enough at first. (See example video.)
The hole need not be big enough for the full height of the sawzall blade. It can be started in about half its full width.
When cutting through the block edges and mortar, angle the saw as shown. Repeat from other side to finish cutting through.
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Best Answer
If you put a couple of sheet metal screws in the joints, and tape them with foil tape, you should be able to do a 5 foot vertical rise with support at the roof boot or where you contact the rafters. You could use straps, but usually the boot if sized properly will be fine if the bottom of the run is supported well.