How better barriers can help your building weather the elements

Whether it’s rain, wind or even the sun, weather is one of the biggest impacts to the structural integrity of a home. Exposure to the elements can wreak havoc thanks to the damage that moisture, condensation and temperature can do to buildings over time.

Homeowners often choose popular exterior finish materials such as stucco and adhered masonry. While these finishes are great at absorbing water when it rains, this creates potential problems with moisture-sensitive materials such as oriented strand board (OSB), wood framing and drywall which lie behind the exterior finish.

Often, destruction is occurring and is unrecognizable until the damage is significant. The good news is that water and moisture damage can be minimized with the proper assembly. It’s not just about minimizing bulk water – moisture and condensation can be just as damaging.

Protecting buildings through better barriers
Typically, if the moisture content exceeds 20 percent, stucco and adhered masonry can start to crumble. When temperatures drop and the dew point is reached, condensation often occurs and the wall assembly can get wet – causing ongoing damage when water and moisture are continuously present over time. In order to remedy the problem, drying must occur not just to the finish materials themselves, but also inward through the high permeability water resistant barrier (WRB) layers that raise the relative humidity in the wall assembly. This process is referred to as “inward solar vapor drive.”

There are two good ways to minimize damage to wall assemblies from inward solar vapor drive:

  • Add a ventilation space between the stucco and the WRB.
  • Use a low permeability WRB like foam sheathing or house wraps behind the stucco to minimize the amount of exterior moisture driven into the wall assembly during rain events.

The best way to avoid these problems is by creating a barrier that reduces water, moisture and condensation from affecting the building in the first place. These kind of weather concerns can make stucco homes last longer and offer a healthier and safer environment for inhabitants.