What size fascia board do you use for 2x6 rafters?
Short answer. A 1x8 fascia, 7 1/4 inches wide, is the standard choice for 2x6 rafters on most pitches. On steep roofs the 2x6 plumb cut grows past 7 inches (about 7 3/4 inches at 12/12), so a 1x10 is often needed unless the rafter tails were trimmed with a level cut.
Plumb cut height on a 2x6 by pitch
A 2x6 is 5 1/2 inches deep. Its vertical cut face gets taller as the roof gets steeper:
- 4/12: about 5 13/16 inches
- 6/12: about 6 1/8 inches
- 8/12: about 6 5/8 inches
- 10/12: about 7 3/16 inches
- 12/12: about 7 3/4 inches
Reading the numbers
- Up to about 6/12: a 1x8 covers the tail and leaves around an inch for the soffit lip.
- 7/12 to 9/12: a 1x8 still works but is tight once you allow for a soffit lip. Check carefully.
- 10/12 and steeper: a 1x10 (9 1/4 inches) is usually needed, or the tails are trimmed with a level bottom cut to shorten the face.
Stick framed homes
Older and custom homes with hand cut rafters often use 2x6 or larger rafters, unlike truss homes with 2x4 top chords. If you are replacing rotten fascia on an older Georgia home, measure the existing board; it may be an older, slightly different actual size than today's lumber.
Practical tips
- Use a 2x6 sub-fascia if gutters will be heavy or the tails are uneven.
- Keep the top edge flush with the sheathing plane so drip edge laps cleanly.
- Back prime wood fascia and seal end grain at every joint.
More on the edge details in drip edge explained and gutter sizing and guards.