2025-09-22 – Weekly Architecture News : Duct vs. Core Wall: A Design Challenge

Last week in our architecture community, discussions were rich and varied. Members debated the challenges and opportunities of a new job opening for a Licensed Architect/Project Architect. There was a lively exchange on the best approaches to product substitutions in specifications, highlighting practical strategies from seasoned professionals. A notable technical discussion revolved around a spray hemp-lime tweak that significantly improved compaction efficiency. The community also engaged in a thought-provoking conversation on the interplay between ductwork and core wall design, exploring how to balance functionality and aesthetics.


This Week’s Hot Topics

Would You Take This Job? – Licensed Architect / Project Architect
Members are weighing the pros and cons of a job offer, sharing insights on what makes a role appealing or a potential challenge.
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How I vet product substitutions in specs
A practical guide on assessing product substitutions, offering valuable tips for ensuring quality and compliance.
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Spray hemp-lime tweak that improved compaction
Discover a small technical adjustment that made a big difference in material performance.
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When a duct trumps the core wall
A deep dive into design conflicts and how to navigate them effectively in building projects.
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Quick CE recs for envelope/curtain wall credits
Fast-track your continuing education with these targeted recommendations for credits.
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The Case of the Disappearing Benches
Explore an intriguing case study on urban design and unexpected changes.
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What’s your go-to stack for fast plaza iterations
A discussion on the best tools and methods for swift plaza design iterations.
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Was Bilbao really the first CATIA-driven building
Revisit architectural history to clarify the role of technology in iconic projects.
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:spiral_calendar: 2025-08-04 – Weekly Architecture News & Trends: Preservation, Public Spaces, and Major Redevelopments
Stay up to date with the latest trends impacting our field.
Read more here

One tweak that kept our FF&E/lighting on schedule
A simple yet effective change that helped a project stay on track.
Read more here


Looking forward to another week of engaging discussions and shared learning. Let’s keep the momentum going.

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On duct vs core wall clashes, I draw a 12-inch β€˜no-fly zone’ around shear walls in DD and require pressure-drop calcs with any spec substitution so duct sizes don’t quietly grow into that buffer… If structure’s already locked, I loop in @struct_kim for a pre-pour sleeve or embedded lintel and issue a quick coord sketch at least 2 weeks before rebar shop drawings, otherwise you’re buying a change order.

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Quick win: I cap duct depth to 14 inches within 5 feet of core/shear walls in DD and swap to flat oval there β€” keeps 9’-0" ceilings and avoids late structural reroutes… For subs, @chawils, we require a one-page pressure-drop calc plus a Revit section snapshot; if height increases more than 1 inch at the core, it’s an automatic no. Only caveat: in labs we sometimes trade 2 inches of corridor ceiling for better static efficiency.

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On a recent hospital tower, we ran a week-2 β€˜core routing huddle’ to lock riser spots, duct elevation bands, and a modest clearance buffer β€” think TSA PreCheck for the plenum. Any substitution had to show the fan curve so size creep was obvious; if the program shifted, we swapped the buffer for MEP β€˜priority lanes’ to keep ceilings intact.

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We added a β€˜plenum lanes’ sheet to DD and made it part of the contract set β€” MEP treats it like a traffic plan around the core. In Revit/Navisworks, a shared parameter caps element height within 4 feet of the core and a search set flags anything over 13 inches, which nips most late reroutes. For substitutions, I only approve if the elevation stays in-band; otherwise it goes to VE, not the field β€” SMACNA’s duct construction guidance is a good referee: https://www.smacna.org/technical; in historic rehabs I’ll loosen the band and coordinate lighting instead.

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