I was told today that the definition "heavy duty" is open to interpretation. this is at best a medium duty frame , it is not difficult to assemble, but it has been opened before & as I have finished building it , putting the feet on & placing the covering, that might be a bit of fussing, tomorrow will tell. The covering is a tarp you can find at Princess Auto 40 dollars, its not a rip stop nylon or in any stretch of the imagination a Heavy Duty fabric, it's a cheap poly tarp , that is the best I can say about it & from experience it will never survive its first Nor 'Easter' no poly tarp I have ever seen has in my life & I am over 60. So If the frame survives I will get a Proper heavy duty covering. Do yourself a favour, buy a frame size you like 2nd hand, then go get a heavy wall welded fireproof scaffold tarp to cover, a tarp like that for a 20 by 10 wide shed will be close to 20 x 30 & cost you 400 dollars you won't have to worry about it for 8 to 10 years.