Pitch For Earthship Roof

On blue prints architects engineers usually display the pitch of a roof in the format shown on the image where number 4 represents a rise and number 12 represents a length.

Pitch for earthship roof.

The earthship s roof perhaps one of the trickiest challenges we faced in this construction project was to build a roof that didn t leak. Two most common methods 4 12 or 4 12 are used for marking the pitch of a roof. Roof pitch or slope is a measure of vertical rise to horizontal run expressed in inches per foot. This measurement is best done on a bare roof because curled up roofing shingles will impair your measurement.

For that reason flat roofs are limited to these types of covering materials. I also share a little about why we did not build an earthship as we had planned because of the climate here. The graphic below helps flesh this out. How roof pitch determines suitable roofing systems.

Pitch is thus the ratio of the rise in inches to a 12 inch run and is often expressed using a semicolon for example 6 12. The picture below shows the pitch of a 7 12 roof slope meaning that for 12 of horizontal measurement roof run the vertical measurement roof rise is 7. A a roof with a 6 rise for every 12 run has a 6 per foot or 6 in 12 pitch. But here in wet southeastern ohio it is a major concern.

Flat and nearly flat roofs a pitch of 1 in 12 or 2 in 12 cannot be covered with shingles or shakes of any material since there is not enough angle to combat the danger of blow off. Since earthships were born out in the desert southwest i suspect the folks out there didn t give it much thought. According to the conventional rule of thumb this would require roof glazing to be about 60 degrees off the horizon 40 20 60. The combination of two numbers are used to display or show the roof pitch.