Drying Documents

BSD-013: Rain Control in Buildings by John Straube — last modified 2008/09/09

Moisture is one of the most important agents leading to building enclosure deterioration. Understanding and predicting moisture movement within and through the enclosure is therefore of fundamental importance to predicting and improving building enclosure performance, particularly durability. Since driving rain deposition on walls and roofs is quantitatively the largest single source of moisture for most walls and roofs, it is no surprise that controlling rain penetration is one of the most important parts of a successful moisture control strategy. In fact, failure to control rain is likely the oldest and most common serious building enclosure performance problem. Commentators as long as Vitruvius (70 BC) bemoaned the challenges of controlling rain penetration. This document will consider rain control from a general to a specific level. The following sections will cover: basic moisture control principles that should be employed in the design of above-grade building enclosures; driving rain as a moisture load on walls; a classification system of the various rain control strategies available for walls; and finally, good design practises for walls. The rain control of roofs will be covered in more detail in another BSD.

BSD-106: Understanding Vapor Barriers by Joseph Lstiburek — last modified 2008/10/17

The function of a vapor barrier is to retard the migration of water vapor. Where it is located in an assembly and its permeability is a function of climate, the characteristics of the materials that comprise the assembly and the interior conditions. Vapor barriers are not typically intended to retard the migration of air. That is the function of air barriers.

BSD-111: Flood and Hurricane Resistant Buildings by Joseph Lstiburek — last modified 2008/08/21

We learn our lessons from disaster. Hurricane Andrew taught us about wind. Hurricanes Charley, Frances and Jeanne taught us about rain. The Red River of the North Basin taught us about floods. Hurricane Katrina had it all: wind, rain and flood. That we will rebuild, and rebuild in the same place, is not in doubt. This is what we do – for better or worse. If we are to rebuild and if we are to rebuild in the same place how should we rebuild?