Professional Background
Hank Yarbrough is an engineer and analyst at JLB Foundation Repair with a professional focus on building science, energy efficiency, and the measurable ways that crawlspace conditions shape whole-home performance. His work sits at the intersection of structural systems, thermodynamics, and indoor environmental quality — the disciplines that explain why the space beneath a house matters as much as any room inside it.
His background spans energy modeling, moisture analysis, and HVAC system performance as they relate to residential building envelopes. Before narrowing his focus to crawlspace science, Hank spent years studying how air, heat, and moisture move through homes — particularly in climate zones where seasonal extremes put constant stress on building materials and mechanical systems. The Midwest, with its humid summers, freezing winters, and heavy clay soils, became a natural laboratory for this work.
That hands-on analytical experience shaped a core conviction: most homeowners receive too little explanation and too much sales pressure when it comes to understanding their crawlspace. The research is clear, the building science is well-documented, and the data from organizations like Advanced Energy and the Department of Energy is publicly available. What has been missing is someone willing to translate that research into plain language without an agenda attached to it.
Areas of Focus
Crawlspace systems are Hank's primary area of research and analysis. Within that broad category, his work concentrates on four interconnected disciplines that together determine how a crawlspace affects the home above it.
Moisture dynamics — how water vapor enters a crawlspace through soil evaporation, foundation walls, and outdoor air infiltration, and how that moisture migrates upward through the floor system into living spaces. Relative humidity, dew point conditions, and condensation risk are central variables in every crawlspace assessment.
Energy loss modeling — quantifying the thermal penalty of unsealed crawlspaces using real-world temperature data, insulation R-values, and air exchange rates. Hank's analysis draws on published research showing that crawlspace air infiltration can account for 15 to 25 percent of a home's total heating and cooling load in Midwest climates.
HVAC interaction — understanding how crawlspace conditions force heating and cooling systems to work harder, cycle more frequently, and deliver less consistent comfort. When ductwork runs through an unconditioned crawlspace, the efficiency losses are measurable and significant.
Indoor air quality — tracing the path from crawlspace contaminants to first-floor breathing zones through the stack effect. Published research confirms that 40 to 50 percent of the air on a home's first floor originates from below, carrying whatever the crawlspace contains — moisture, mold spores, soil gases, or volatile organic compounds from degrading materials.
Approach to Building Science Communication
Hank writes the way he analyzes — with specificity, sourced data, and respect for the reader. Every article published through the Crawlspace Energy Institute includes references to peer-reviewed research, government studies, or field data from recognized building science organizations. Claims are grounded in measurement, not marketing language.
His goal in every piece of content is straightforward: give homeowners enough knowledge to understand the physical processes happening beneath their floors and evaluate any recommendation they receive with genuine confidence. That means explaining the stack effect in terms of pressure differentials, not scare tactics. It means presenting encapsulation research alongside its limitations. It means acknowledging that every home is different and that climate, soil type, foundation design, and existing conditions all influence the right course of action.
Complexity is not an excuse for vagueness. Building science has clear principles, reproducible measurements, and decades of published field data. Hank's writing makes that body of knowledge accessible without oversimplifying it. If a topic requires nuance, he provides the nuance. If a common assumption is contradicted by research, he presents the research and lets the data speak.
Why Crawlspace Energy Institute
The Crawlspace Energy Institute exists to be the educational resource Hank wished existed when he first started fielding questions from homeowners about their crawlspaces. Most of the available information online is either too technical for a general audience or too shallow to be genuinely useful. Manufacturer spec sheets assume professional knowledge. Contractor websites focus on selling services. Academic papers are locked behind jargon and paywalls.
This site fills the space between those extremes. Every article Hank writes for the Crawlspace Energy Institute is designed to stand on its own as a complete explanation of its topic — grounded in research, written in clear language, and structured so that a homeowner can finish reading and actually understand what is happening in their home. No pressure, no urgency manufactured for its own sake, and no shortcuts on the science.
The result is a growing library of crawlspace science content covering the stack effect, moisture control, encapsulation methods, insulation performance, dehumidification, structural considerations, energy modeling, and climate-specific guidance for Kansas City and Des Moines homeowners. Each piece connects to the others, because crawlspace performance is a system — and understanding any one part requires understanding how it relates to the whole.