Mueller 18x21 (D.I.Y.) with Optional Center Girts and Floor Kit - Manual (Page 25)

Mueller, Inc. 18x21 DIY Back Yard Kit Instructions; For additional information, see the D.I.Y. Installation Video
1"
25
sHeeTING sIDewall
Inside closure goes on the bottom and outside closure goes on top.
sidewall
endwall
NOTE: Start sheets 1" above the bottom of the base channel and 1" out from endwall
TOP VIEW