Roof Pitch Leaves the Curb or Duct Connection Out of Alignment

Fast answer

Verify the curb, support rail, equipment, and duct connection elevations from the approved roof and equipment references before fabricating a field transition.

What to check

1. Confirm roof slope and high/low side elevations.
2. Check curb and equipment orientation.
3. Measure supply and return openings independently.
4. Verify roofing, insulation, and service clearances.

Do not

Do not level the connection by crushing gasket, twisting flex, stacking loose material, or altering the curb without approval.

Ask the foreman

“The roof pitch puts the equipment opening out of alignment with the interior drop even though the plan dimensions match. I measured both curb sides and the duct elevation. Can we verify the approved adapter or support correction before fabrication?”

Why it matters

A roof-slope mismatch can transfer load, compromise weather seals, distort connectors, and create drainage problems.