**Install the main ductwork before the cabinets.** With a new exterior vent and ducting above the cabinets, you’ll have better access for cutting openings, supporting the duct, and sealing joints.

The practical order is:

1. **Choose the hood and finalize the cabinet layout.** Use the hood’s installation instructions to establish duct size, outlet position, and clearance above the cooking surface.
2. **Install the exterior vent and main duct run**, leaving the final connection at the hood accessible.
3. **Install the cabinets**, with any required duct openings.
4. **Mount the hood and complete the duct connection**, then finish any enclosure or trim.

This follows [Broan-NuTone’s installation sequence](https://www.broan-nutone.com/getmedia/8acb9d19-de80-4d34-8f84-777e4e620d71/Installation-Guide-AHSA1.pdf?ext=.pdf), which starts with the exterior cap and metal ductwork, working back toward the hood location.

Coordinate the duct installer and cabinet installer before either starts: the duct must fit above the planned cabinet height and align with the hood. Use smooth, rigid metal duct sized for your chosen hood, with a short route and few elbows; discharge it outdoors. [Broan-NuTone duct guidance](https://help.broan-nutone.com/en/range-hoods/What-type-of-duct-is-best-for-venting-a-range-hood-6a1b)