I found that it’s difficult find a Quonset hut that is large enough that is less than $1000. I wanted it to be 9 x 30 feet and to be able to stand up in the cockpit. I decided to make my own Quonset Hut. I started with a 25’ x 40‘ tarp (Ultimate grey tarp from WM on sale for $90). The structure is made of ½” id PVC electrical conduit. The 21 ribs are 26’ long on 18” centers and screwed to the 5 each 30’ stringers with #10 1 1/4 “ sheet metal screws. I laid out all the conduit on the deck, drilled thru holes in the 5 stringers every 18” and smaller pilot holes in the 21 ribs at the middle and 6” and 6’6” from each end. I screwed them together from the inside so there are no screw heads on the outside of the ribs to wear the tarp. Materials required is 3 x 21 pieces of conduit for the ribs and 5 x 3 pieces of conduit for the stringers - for a total of 78 pieces of conduit. The ½ “ conduit cost .92 each so the total cost was $71.76 at Lowe’s. To get the height I wanted I used 3 pieces of 3” id conduit to support the mast which was cable tied to the inside of the structure (2 each 10’ lengths at $10). So the whole project cost must have been about $200 with screws & taxes. Note that the 40’ tarp nicely wraps the ends without overlap. I didn't mention the first step was making two rows of 21 holes 18" apart in the ground alongside the trailer about 6" out and 9' apart. Into these 21 holes goes the lowest 6'' of each rib
