How Much Should Roof Sheathing Overhang

It is at 45 3 4 in.

How much should roof sheathing overhang.

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

Roof sheathing overhang on fascia. A typical metal roof overhang may be 2 to 4 inches or even less. Overhangs can vary from a few inches to a few feet depending on preference. The edge of the shingles should hang over a roof between an inch and an inch and a half or between a half inch and three quarters of an inch if drip edge flashing is installed.

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. This is to just enough to cover the 3 4 x6 actual fascia. Too little can allow water to seep into rake or fascia boards. Measure up the rafter 45 3 4 inch from the cut end of the truss tail and snap a line along the trusses.

The drip edge also gives us a nice straight edge with which to align roof shingles slates or other roofing material. Too much overhang and the shingles could blow off in high winds. Slide the sheet one rafter width over the end of the roof so the edge is centered on the next rafter offset one rafter spacing from the first piece of installed sheathing from the row below.