Modern construction has proven to produce buildings that are more square, move less creating less maintenance, and have energy efficiency capabilities that few could have foretold. Because of the different methods of framing, we have been able to produce homes in a significantly short amount of time, from start to finish, sometimes in less than 6 months from completion to move in day. However, because of the fast construction methods that we use, sometimes problems arise that we do not catch until the project is far from over. One such issue that is common is the sweating of hurricane clips, a small clip that is nailed to the bottom of the truss/rafter and the top plate of the house.
Hurricane clips got there name because their original design was literally to keep the roof on the house during a hurricane. Because of the strong winds during a hurricane (over 100 miles per hour in many cases), the wind flies up through the soffit venting and pushes up on the sheeting of the roof. This creates a lifting affect. In fact, there are several videos of homes where one entire side of a roof is lifted right off the wall from winds like these. The hurricane clips tie the roof structure to the wall structure anchoring the roof structure down. This simple method also has prevented truss uplift, caused from the shrinking and expanding of the trusses from season to season.
How They Are Installed
Hurricane clips are installed using 1 1/4 inch galvanized nails in 5 holes in the both parts of the clip; the portion on the top plate and the portion on the truss, rafter. They are installed on every single truss/rafter and, by code, have to be nailed through every single hole to be properly secured.
How These Clips Cause Mold
Hurricane clips are typically installed on the interior walls of the building, with the drywall installed directly over them as they extend down 2 to 3 inches on the wall. During the winter time, the metal hurricane clips absorbs the cold from the exterior of the building. The warm air escaping along the edge of the building causes the hurricane clips to sweat which causes water to sit on the back of the drywall. Because drywall backing is food for mold, it does not take long to start to see that black blotches under every ceiling joist where the hurricane clips are.
Properly installed vapor barriers can help prevent this, but in homes that were constructed between 1987 to 2004 where the construction practices do not require vapor barriers to be taped and sealed, moisture issues can arise in strange places, such as the middle of walls.
The Easy Solution
To prevent any chance that a mold issue will develop from hurricane clips, this smart invention can be installed on the exterior wall where it has no threat of moisture damage as the exterior temperature is nominal throughout. The hurricane clips are just as effective. This also allows for easier drywall installation.
Hurricane clips are one of the many smart and simple solutions that people have come up with to battle mother nature in times of turmoil. Install them on the exterior of a home for problem free application.