Blog
Remediating blocked soffit-to-ridge venting around skylights in a cathedral attic – GreenBuildingAdvisor
- September 16, 2026
- Posted by: adm_2zyc7xf0
- Category: Uncategorized
I’m seeking feedback on a venting solution for a new construction project in cimate zone 4B.
- Roofing: Metal roof over plywood deck.
- Assembly: Hybrid conditioned attic. R-49 fiberglass batts will be wire-hung from the 2×4 top truss chords, capped on the interior with taped Tyvek.
- Venting: Continuous heavy-duty rigid baffles to maintain a 2-inch air gap from the soffit to the ridge.
- The Obstruction: There are four skylights already installed (two on each side of the ridge) that completely block the linear bottom-to-top airflow path within those specific truss bays.
The Proposal:
For what it’s worth, I asked an LLM (Gemini) to suggest a solution to propose to the architect and this is is what it came up with:
- Drill a cluster of three 2-inch holes horizontally through the 2×4 top truss chords immediately below each skylight header, and another cluster of three 2-inch holes immediately above each skylight header.
- Holes will be vertically centered in the 2×4 members (leaving ~3/4″ of wood on the top/bottom edges) and spaced 4 to 6 inches apart on center to protect structural integrity.
- Terminate the rigid ventilation baffles 6 inches before these hole clusters so air can detour horizontally into the adjacent, unblocked truss bays.
My question: Is this a sound approach for handling the blocked bays, or are there better ways to handle skylight obstructions in a hybrid attic like this? I can’t get rid fo the skylights at this point – the ideal is to get the builder to do something helpful before the insulation is installed. Thanks in advance for any advice.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Search and download construction details
Join the leading community of building science experts
Become a GBA Prime member and get instant access to the latest developments in green building, research, and reports from the field.