How Much Should Roof Sheathing Overhang

Too much overhang and the shingles could blow off in high winds.

How much should roof sheathing overhang.

This indicates the upper edge of the first row of roof sheathing leaving enough overhang that the subfascia and fascia will tuck neatly underneath when the time comes. However the suggested width of an overhang is between 12 and 18 for eaves and no more than 8 for rakes. Drip edge varies in dimensions but typically the flange that nails to the roof surface is about 2 5 wide and the vertical edge that directs roof runoff down and away is about 1 5 in depth. When ordering the sheathing divide the total number of square feet of roof surface by 32 square feet a 4 x 8 panel and add an extra 15 for waste.

Overhangs can vary from a few inches to a few feet depending on preference. A typical metal roof overhang may be 2 to 4 inches or even less. Metal is usually installed on rafters or strip sheathing rather than the solid decking used under other materials. Too little can allow water to seep into rake or fascia boards.

This is to just enough to cover the 3 4 x6 actual fascia. I ve trimmed my roof sheathing to run between 5 8 and 3 4 over the sub fascia. It is at 45 3 4 in. Some slight overhang is recommended in conjunction with a drip edge flashing to prevent water from getting under the roofing and onto underlying wood.

The drip edge also gives us a nice straight edge with which to align roof shingles slates or other roofing material. Thickness will range from 3 8 to 3 4 inch depending upon local code. This would add another 3 4 to the thickness. Now that i ve modeled what i was going to build i decided i need a piece of molding to break up the plain look of just the fascia trim plank.

Choose an exterior c d grade.