Measured mine.
Living area opposing slides
Dining / Entertainment Slide - 43" from trailer wall to extended slide wall
Sofa / Fridge / Stove Slide - 28 1/2 "
There is an awning on the Dining Slide (curb side) which add 5 1/2 inches to the clearance needs.
That gives me a total external width of 14 ft 6 inches for clearance.
But my bedroom slide is 39 1/2 inches wide - so I actually need 15'7" unless I angle the TT into a site.
I also need that width 9 feet 10 inches above ground level.
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In general "deep slides" tend to be about 42" deep. Normal slides 30" deep. Bedroom slides with a bed run about 40" deep and closet slides about 24" deep.