#Rafter tails design minimum overhang upgrade

I observed that the architect had drawn the Dutch Hip ends to be framed in the standard method where short hip rafters frame to butt into a set of paired common rafters positioned at some distance in from the end of the building. With the birdsmouth located mid length along the rafters and the rafters themselves having varied sized crowns, you can easily imagine the extra time that will be involved in jockeying the tails up/down to create a straight fascia line. Reviewing the plans, I noticed that the ratio of eave’s overhang distance to common rafter run was near 1:1. While in latitudes farther to the north this would cause snow-loading problems, in the tropics-where lightweight metal roofing is the norm and nothing other than rain (or perhaps an occasional coconut) loads the roof surface-one would suffer no dire consequences from the design. Of course, with tails that long, one could anticipate a struggle when running the fascia.

I sure hope it works, since in this climate, mold and termites can knock an untreated wood structure down almost as fast as one can put it up. All the framing was to be done with imported treated Honduran pine, some strange wood that I had never heard of before. tall and open above to the roof, similar to work station cubicles in a large office. The rising air would draw cooler air in through the windows, facilitating a constant movement of air through the house, somewhat like how a chimney draws air up and out of the fireplace. The interior partition walls were 8-ft. During the day, the tropic sun would bake the metal roofing, which in turn would transfer some of its heat to the air below the sheets and that hot air seeking to rise would find its way out these vents. tall exterior walls. The ceiling was “open frame” style, 2×8 rafters/ridge at 5/12 pitch with 1x T&G decking above. The Dutch Hip’s tiny gable end walls were only to be perimeter framed then screened off to serve as roof vents. The buildings were relatively narrow with 10-ft. Only at night did the temperatures become bearable in this carpenter’s honest opinion. This style is very effective in the tropics. It incorporates huge overhangs to provide both abundant shade from the brutal sun and extra coverage around the house for the torrential rains during the monsoon season (averages of nearly 20 feet of rain per year). During the day, while I was there, temperatures in the shade were always in the 90s accompanied by skin-soaking humidity of 90% or higher. Nail through the face of the outlook into the notch of the outer rafter, and you’re ready for subfascia.Panama Canal Zone Gamboa Design (Note: Click any image to enlarge) Make sure to square up the outlooks before nailing them through the inner rafter. The 3.5 x 1.5-inch notch should be spaced every two feet and placed to land where roof sheets will break.Ģx4 outlooks should extend back to the second rafter and past the first one by whatever the overhang is minus the thickness of the subfascia. It involves notching the outermost rafter to accept 2x4 outlooks. It will be done with a similar ladder frame, but the system is a little more involved than blocking.

#Rafter tails design minimum overhang upgrade

This works great for small overhangs, but what if you want to upgrade to a deeper overhang? How is that framed? Deep roof overhangs must tie into existing framing Subfascia ties together the bottom, and roof sheathing acts as a structural diaphragm above to form a torsion box of sorts.

In another animation, we assembled a simple ladder-block overhang and nailed it through the wall sheathing into a rafter. Before slapping down plywood, though, you need to frame the gable overhangs.