Every builder and architect knows that keeping a building dry, comfortable, and energy efficient depends heavily on controlling air movement. But what physical principles govern that air movement? The answer traces back to one of the most fundamental rules of physics: the second law of thermodynamics. This law, which describes how energy tends to disperse […]
Mean radiant temperature (MRT) is one of the six fundamental factors that determine human thermal comfort, yet it remains one of the least understood concepts in building science. While most people are familiar with air temperature readings from a standard thermostat, MRT accounts for the thermal radiation exchanged between a person and the surrounding surfaces.
When it comes to weather-tight window installation, builders have more options than many realize. From sloped rough sills and back dams to site-fabricated sill pans and liquid-applied membranes, the toolbox for sealing windows against moisture is diverse. One decision that often goes unexamined, however, is the order of operations between the window and the water-resistive
The adoption of the 2021 International Residential Code (IRC) and International Building Code (IBC) brought significant changes to insulation requirements across climate zones 4 and 5. Builders and designers who previously relied on a simple 2×6 wall with R-20 cavity insulation now face the need for additional continuous insulation. One approach that has gained attention
Mass timber construction has gained remarkable momentum across the United States over the past decade, but the southeastern region holds particular promise given its abundant forest resources and expanding manufacturing infrastructure. While many high profile mass timber projects such as the Ascent in Milwaukee and Bowdoin College buildings in Maine have relied on imported European
Water is the single most destructive force that buildings face over their service life. From the foundation to the roof, moisture infiltration can compromise structural integrity, degrade insulation performance, and create conditions where mold thrives. The principles outlined in William B. Rose’s work on moisture and mold provide architects and builders with a scientific framework
When it comes to protecting a home from moisture damage, few components are as critical yet as often overlooked as the vapor retarder in crawlspaces. The crawlspace is uniquely vulnerable to moisture intrusion from the ground below, and without an effective vapor retarder, that moisture can migrate into the living space above, causing elevated humidity
Radiant floor heating remains one of the most comfortable and energy-efficient ways to heat a home. In a hydronic system, a boiler or heat pump circulates warm water through plastic tubing embedded in the floor, warming the entire surface from below. When designing such a system, one of the most important decisions you will face
Humans are remarkably good at sensing temperature. Most building professionals can guess the air temperature in a room within a few degrees Fahrenheit without looking at a thermostat. But when it comes to humidity, the same professionals often miss the mark by a wide margin. Understanding and measuring the moisture content of air is far
Understanding Polyiso Insulation Performance in Cold Climates When designing building envelopes for cold climates, specifying the right insulation material is one of the most consequential decisions a design professional can make. Polyisocyanurate (polyiso) rigid foam insulation has long been favored for its high stated R-value per inch, typically R-5.6 to R-6.0. However, the performance of
