Roof Sheathing Over Fascia Board

Installed a new fully adhered membrane to the top of the old board sheathing prior to adding all that rigid insulation.

Roof sheathing over fascia board.

Installing the fascia before sheeting the roof solves a lot of problems. Where should roof drip edge flashing be placed. During house construction fascia boards are fastened to the ends of the rafters called rafter tails before the roofing and gutters are installed sometimes there are two fascia boards either the same width or different widths with a narrower board in front of a wider board and sometimes fascia is installed over a board of framing lumber called subfascia that mounts directly to the. This opens the door to the possibility of water damage by letting gravity work.

I ve trimmed my roof sheathing to run between 5 8 and 3 4 over the sub fascia. Most of the roof runoff is going off the roof not down the fascia board. This is to just enough to cover the 3 4 x6 actual fascia. This would add another 3 4 to the thickness.

Run fascia the thickness of the plywood higher than the fly rafter on the gable and flush on the sub fascia. Then i do a metal drip edge to cover it all. Roof edge detail overhang extended to hide the thickness of the over roofing rigid insulation. 4 reduced roof tile overhang by capping over the boards the guttering will be set slightly further away from the roof tiles this may cause rain water to run behind the gutter rather than into it.

Draw a full scale mockup and snap a line with fascia in kind when sheathing a roof the first step is to snap a line so that the first row goes on straight. On my shed my sheathing does not protrude actually how both my house and shed are done is a 1 x 6 house 1 x4 shed fascia is installed to end of rafters then 1 x 1 1 2 is tacked onto the fascia at the top. This is a known issue that is directly caused by capping over the fascia instead of doing a proper job and replacing it. But if you snap it at 40 inches then the sheathing will not project over the subfascia or true fascia.

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. I install the fascia flush with the top of the sub fascia. Chalk your line up the rake 48 from the point where fascia meets sub fascia.