How To Frame A Bell Roof

Has anyone ever framed a bell shaped roof befor that s octagon shaped and if so how did you cut your common and jack rafters.

How to frame a bell roof.

Jlc had an article in this months issue may and the author cut all the normal from plate to ridge and plate to hip. A super basic a frame roof will require anywhere between 4 and 8 depending on the size of the rafters with plumb cuts necessary for each angle in the brace. So far i have made them using sweeps but that is causing issues with the apearence of the roof pl. Hello all i work at a company that does custom homes and renovations and i am attempting to swich us over from cad to revit.

Larger roofs may be covered by using inch boards and bending them around the roof at an angle of 45 with the plate. The problem i am having is that pretty much all our roofs are bell curved. Framing bell shaped roof we do it in a very similar manner but cut the plywood on the cnc then create modular sections that are delivered to the site bolted together and then lifted as a unit. Make yj equal to y w the length of the shortest rafter and drawy je and jd.

After the framing was complete they sheathed the roof with two layers of 3 8 in. Then the angle which je or jd makes with the foot of each rafter will be the cheek cut of that rafter on the roof and a line g v drawn from the foot of each rafter y g will give the angle yg v which is the bevel of the foot cut of each rafter as it rests upon the roof vp. Ultimately the timber bell frame will rot with fungal decay or invite death watch beetle which favours damp oak. Depending on the design of the trusses you re making any number of bracing joints will be necessary.

For small roofs it is necessary to cut the boards to a wedge shape and put them on vertically nailing to the circular ribs. Review of basic geometry pythagoras theorem and similar triangles needed for roof calculations. When builder noah woodruff was hired to replicate a small 18th century building his biggest challenge was its bell shaped roof. I m framing a house ion spring lake new jersey and there are quite a few of these roofs.