I love projects and I love cupolas so it was fate that these two should meet. This is project cupola.
I should explain. A cupola looks like a little shed on top of a barn roof. It is there to promote ventilation. Projects are something I do in my shop to keep me from going nuts during the long, gray forth season known as winter. There, now you’re up to speed.
I began the cupola on a ladder. I climbed to the gable-end peak of the shop roof and laid two boards on end along the roof-line so I knew their angle. I then ran screws through the boards where they met. I took this newly-formed template into the shop and screwed it to my workbench. Everything I built from this point out would depend on the accuracy of my template so I checked it several times then began my work.
The base of the cupola really just needs to transfer the weight of the structure to the roof. The base is sturdy but I was more concerned with it being rigid laterally than anything else. The top side of the base structure consisted of two by fours and covered by a ¾ inch thick piece of osb. After I formed the skeleton of the base, I wrapped it in red barn steel on the side and coil stock on the top.
The top of the cupola was formed by cutting two semi-circles from a sheet of ¾ inch oriented strand board (osb.) I then stood both semi-circles on their flat side 48 inches apart and screwed two by fours to span the distance between the sheets of osb. I formed a structure in between the two by fours where they met the semi-circle of osb with more two by fours which created an almost-semi-circular frame on the interior of the top portion of cupola. If you are lost by now, don’t feel bad. Re-read the previous three sentences and you will probably still be-lost.
It was now time to mount the top to the bottom. I made wooden posts from a sandwich of two by fours and osb. I needed to leave a channel open in the middle of each post so that a half-threaded rod could be passed through it. I used the threaded rod to squeeze each two foot post in between the top and bottom which created an open space, kind of like a church steeple. I also threaded 14 gauge wire through one post as I wanted to mount a light from the bottom of the top part of the cupola.
The roof of the cupola is covered in galvanized steel. I cut the galvanized steel so that it hangs about two inches over each side of the osb board which forms the face of the top. The face of the cupola was covered in red barn steel and slotted into flexible j-channel which rides the upside-down curve formed by the bottom of the galvanized-steel roof. The four bare-wood posts were then covered in Versatex column wrap which was glued and fastened into place.
My nephew, Ben Nelson, brought his bucket truck out to lift the cupola into place. He also let me ride along so I could finish up the wiring. The light is mounted to the “ceiling” of the cupola and is on a photovoltaic switch. I typically overbuild and the cupola was no different as Ben and I had to carry it out of my shop which proved to be a real “milk strainer.”
I included pictures but you’ll notice the cupola gives my shop a southern colonial look to it. This was unintentional as there was no plan included with this project. Anyway, I think it looks nice and it always good to lean on a project as I limp through winter.