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ROT Can Cause Duct Issues – Short #160

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In this short podcast, Bryan explains how rules of thumb (ROT) can cause duct issues. He talks about the role of friction rate in duct design as well as its intent and limitations.

Friction rate is a value located on duct calculation tools, including Ductulators. We use friction rate to predict the operating static pressure of the system, but it is often misapplied when people design their ductwork around rules of thumb. The friction rate is expressed in inches of water column (“WC), which we also use to measure static pressure. However, the operational static pressure and friction rate are NOT the same things.

Ductulators provide information about friction rate based on 100 feet of straight ductwork in the size selected, which we almost never see in the field; fittings and turns add effective length (EL), so the total effective length (TEL) is often more than 100 feet. When duct designers apply rules of thumb, like a 0.1″ friction rate, and apply it to the CFM, they don’t consider the actual length of the duct. So, the ducts are often undersized and don’t properly account for the actual resistance to airflow.

If you want to stop using rules of thumb, ACCA Manual D and related software can help you get more precise design parameters and account for other restrictions.

The following tech tips contain more information and specific equations to help you find the total effective length: The Friction Rate Chart (and What it Means), What the Heck is a Friction Rate? (Eric Kaiser), How to Determine the Friction Rate for Residential Duct Design (Neil Comparetto).

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In this live stream episode, Bryan sits down with Tony Gonzalez, who has spent more than 25 years at Fieldpiece and now leads the company’s training department. Tony started out packing boxes in the warehouse straight out of high school, and the two longtime industry veterans use his experience to dig into why culture matters so much when you are building a business that lasts. As Bryan puts it, culture may be talked about in HVACR, but it is true everywhere.

Tony walks through TURTL, the five core values that anchor Fieldpiece’s culture: Tribe, Upfront homework, Right stuff, Trust, and Lean. The missing “E” is intentional, since it reminds everyone to leave their ego at the door. He explains why values can’t be purely aspirational, and how Fieldpiece keeps them alive through recognition, one-on-ones, and development reviews. Bryan shares how the same ideas show up at Kalos, including the phrase “professional pride, personal humility.”

The conversation then turns to leadership, which both guests agree is where culture is won or lost. They discuss why your culture is defined by the worst behavior you tolerate, why people stay at a company, and why curiosity should come before judgment. Tony describes the “bank account” of care that makes hard conversations productive, along with the Radical Candor idea of avoiding ruinous empathy. Bryan adds that clarity is kindness and that small problems should be dealt with before they become mountains.

They close by looking at team building, using Bryan’s flight crew analogy and the “right people on the bus” idea from Good to Great. Every role matters, leaders shouldn’t only hire people like themselves, and snap judgments can make you overlook great talent. Bryan wraps up with a few of his leadership commitments, and Tony’s final advice is to start documenting what matters to your organization, live it consistently, and give yourself grace on the leadership journey.

Topics Covered:

Tony’s 25-year career at Fieldpiece, from warehouse to head of training
The TURTL core values and why “Turtle” has no E
Keeping core values visible through quarterly recognition, one-on-ones, and development reviews
Leaders as culture carriers, and how culture shows up when things go wrong
Defining culture as a social operating system and the worst behavior you tolerate
Professional pride and personal humility, and leaders who celebrate their team’s success
Why people stay: growth, recognition, fair compensation, and connection to the mission
Curiosity before judgment, root cause thinking, and celebrating failure
Making “deposits” of care so difficult conversations go well
Radical Candor, ruinous empathy, and clarity is kindness
Handling bad news and building a safe environment for people to speak up
Building a flight crew: hiring for attitude, valuing different strengths, and avoiding the horns effect
The weakest link in the chain and treating every role as equally important
Book recommendations: Good to Great, The Power of Company Culture by Chris Dyer, and Delivering Happiness by Tony Hsieh
Bryan’s leadership commitments: truth over comfort, open doors with no gatekeeping, and people over plans