Gable porch

The showpiece addition: two columns and a front beam, side beams butting its inner face and running back to the main wall, a ridge board out from the wall, rafter pairs plumb-cut to it and birdsmouthed over the side beams, purlins, skin, mitered rake boards, eave fascias on the tails, a bent ridge cap and wall flashing where both slopes die into the main wall.

Also called: projecting gable · entry porch · timber truss porch · king post truss

1. 1Depths follow the published ladder (6/8/10/12ft) and posts land on 8/10/12ft spacing — 'corners and every 12 feet'.
2. 2The ridge board's LEVEL top face lands on the rafter top at the ridge FACE, so nothing pokes above the roof plane.
3. 3Rafters tail PAST the side beams to a plumb cut at the fascia, so the roof and fascia are carried rather than floating.
4. 4The decorative king-post truss is bottom chord bearing on the front beam, king post standing ON the bottom chord, top chords mitered plumb at the peak and seat-cut at the heel — and it is only drawn when the gable actually has room for one.
5. 5An open porch deliberately shows daylight and the timber truss through the gable; an enclosed one is sheeted.
6. 6A per-porch concrete slab toggle pours a pad measured at length times projection, kept in lockstep with the catalogue service line.

• ◆Decorative timber drawn floating off its bearing.
• ◆Porch pads quoted separately from the porch.