Green Police, Real Talk: Rants That Actually Make Buildings Better
Ranting as a Building Science Service
When you put Michael Anschel and Carl Seville in front of a BS and Beer crowd, expect a bit of chaos, plenty of opinions, and more useful insights than any polite panel usually offers. This particular discussion covered topics such as low-carbon concrete, certification challenges, humidity issues, and the ongoing foam versus mineral wool debate. Despite the humor, there were clear lessons for anyone working on real buildings.
Low-Carbon Concrete: Worth Asking About, Not a Magic Solution
The first audience question addressed low global warming potential concrete, a concept many have heard of but few have specified. The group discussed mixes that inject carbon dioxide into fresh concrete or use alternative binders to reduce Portland cement, noting claims of significant carbon reductions. However, they agreed this is not yet a standard choice.
Carl explained the basics: Cement starts as limestone, which releases a lot of carbon when heated. Over a building's life, concrete absorbs some carbon, but not enough to offset what was released. The practical takeaway is to ask your ready-mix supplier about lower-impact mixes with real data, and use them when appropriate. However, the biggest impact often comes from using less concrete in foundations and slabs.
Programs That Help and Programs That Hinder
Carl spends much of his time helping multifamily projects navigate Energy Star and similar certifications, which can be complex. Version numbers change, revisions appear, footnotes multiply, and rules shift with permit dates, so a small delay can force a project into a new set of checklists.
While no one argued against standards or accountability, the discussion highlighted how paperwork can overshadow performance. Michael noted that rules with good intentions can accumulate until they hinder the outcomes they were meant to support. The suggestion is not to abandon programs but to continually ask: Is this requirement helping us build better homes, or just slowing us down? If the answer is unclear, it may be time to push for simplification.
Humidity, Oversized Systems, and the Tool Everyone Avoids
When the conversation turned to comfort and moisture, things became concrete. Carl frequently encounters multifamily projects in humid climates where small apartments have large cooling systems, steady ventilation, and no real dehumidification plan. Units short cycle, barely removing water from the air, leading to mold issues.
Developers often hesitate to invest in dedicated dehumidifiers, despite later spending on remediation and complaints. In single-family homes, high-efficiency heat pumps and mini-splits can perform well but leave homes clammy during shoulder seasons or at part load, especially when the only dehumidification option lowers the temperature too much.
The group emphasized a straightforward point: In climates where summer air feels swampy, a properly sized and installed dehumidifier is usually the right tool. Relying solely on cooling equipment for dehumidification often creates new problems.
Foam, Mineral Wool, and Life at the Foundation
The insulation discussion focused on foundations, where mineral wool and rigid foam are both used to improve performance. Michael described job sites where mineral wool boards, initially neat and square, were damaged by backfill, machinery, and daily work. By the time walls were erected, some sections were damaged or missing.
Travis countered that careless crews treat foam boards similarly, suggesting the issue might be design and supervision rather than the product itself. If a delicate layer is expected to survive in a tough location without protection or follow-up, results will likely not meet energy model promises.
The group acknowledged foam's real climate impact and that marketing often highlights one aspect of its footprint while ignoring resin and manufacturing. They admitted that certain foundation conditions, especially in colder regions, still require some targeted use of below-grade foam.
The middle ground is:
Use mineral wool where it can be supported and protected, and where crews know how to handle it.
Treat foam as a limited, intentional material rather than applying it everywhere.
Design foundation details considering the mess of excavation and backfill, not just clean drawings.
Keeping People and Buildings at the Center
Despite the venting, the conversation ended on a grounded note. Carl mentioned his grandchildren, who remind him that better buildings are not just a hobby. Michael spoke about uplifting people rather than wearing them down, whether by complimenting a crew on air sealing or inviting more voices into the building science community.
If you distill their discussion into a few key ideas, consider these:
Focus on health, durability, comfort, and total carbon, even when programs and products try to narrow the debate.
Use labels and certifications as tools to support judgment, not as replacements for it.
Match materials and details to actual building practices, and protect assemblies needing more care.
Final Pour
Ultimately, all the rants pointed to a simple truth: Better buildings don't result from one miracle product, perfect standard, or clever detail. They come from people who remain curious, honest about what works and what doesn't, and who continually ask what will make a home healthier, more durable, and more comfortable for its occupants. Keeping that question in mind is the essence of building science, even if it involves some laughter and complaints along the way.