When it comes to a leak-free building, the sealants are the backbone of the whole cladding system. Even the best exterior aluminum, masonry, glass, steel, or exterior insulation and finish systems (EIFS) are only as good as the sealants used to weatherproof the joints, penetrations, and transitions of the cladding system being specified.
At this point, most design/construction professionals have a pretty good understanding of the need for well-designed air and moisture control layers in wall assemblies. Water-resistive barriers (WRBs) have been in use for decades; in more recent years, a number of new systems have popped up that combine these products with an air barrier function.
Global warming could increase lightning strikes by 50 percent, according to recently published climatological research. The distribution of lightning activity may also change, raising the occurrence of lightning in regions that heretofore had little risk.1 At the same time, the need for lightning protection becomes more urgent as buildings are filled with increasingly sensitive electronic devices.
Industry codes are tightening the building envelope and increasing the required R-value of walls. This is a good thing for energy savings and thermal comfort. Yet, one change to a building’s system sets forth a series of other changes. The tight-envelope construction techniques to which architects and builders are now required to adhere have led to a steep reduction in air movement through walls.