7 Minutes of BS (#BuildingScience w/a BEAT)

Dark roofs absorb heat, and light roofs reflect it. Light roof shingles—combined with more insulation in the attic— can go a LONG way towards reducing the heat stress people in southern climates experience three seasons of the year.

Dr. Joe Lstiburek explains the fourth state of water: ADSORPED water. It exists on surfaces as tiny monolayers that can fill pores on the surface and cause mold. It also explains why expansive soils expand. If you thought you understood diffusion and capillarity, buckle up.

Vapor Diffusion Ports: Air Barriers That Let Moisture leave Dr. Joe Lstiburek explains what Vapor Diffusion Ports are, how they work, why they're needed, and how to construct them—in about nine minutes. The skinny version: they're like a modified ridge vent but for an unvented roof. They allow moisture to escape unvented roof assemblies without letting air leak out.

An overview of water, the liquid that makes life possible, rots buildings, and makes great wine.

In this episode, we are joined by Dr. Joe Lstiburek, out favorite crawlspace buddy, to talk about the origin of hot roof and cold roof labels.