By Esme Purdie, WIR Contributor
We all know the tale of the three little pigs: The big bad wolf wanted to blow down their houses. The first house was made of hay, the second of sticks, and the third of brick. The big bad wolf blew down the first two, but the third house wouldn’t budge.
They were doing it wrong: Imagine the Big Bad Wolf is a Hurricane. What type of house could save the 3 Little Pigs? A “hurricane house” built from Southern Yellow Pine. Here’s why.
The Big Bad Wolf = Hurricanes
Hurricane Katrina. Image via NASA
From the Northeast to the southern tip of Florida, hurricane season can put fear in the hearts of homeowners. And when the storms come, they hit hard. In 2014 there were 5 severe storm events, each one causing over a billion dollars worth of damage as well as countless smaller storms.
Building a new home, especially in the most hurricane-affected areas, means storm and hurricane resistance has to be considered. Many coastal regions have put strict building codes in place to try to protect people and their properties.
Storm Resistant Houses Built with SYP
Building a storm resistant house does not mean it has to be built from bricks, no matter what those three pigs in the fairy tale say. In fact, it is possible to design wooden frame structures that can withstand hurricane level winds and storm surges. Post-and-beam or log-cabin, two of the most traditional wood construction methods are able to withstand earthquakes, tornados and hurricanes, as long as they were built properly and timber is strong and durable. Regulations now specify building techniques as well as how foundations, walls and roof are connected, even the nail patterns and the metal strapping that should be used.
Image via Shutterstock
The type of wood you use is extremely important and Florida’s Department of Community Affairs (DCA) building code specifies new homes along the Gulf coast plan use Southern Yellow Pine (SYP) in the structure, as its strength, flexibility and durability mean it is able to withstand 150 mph winds.
Southern Yellow Pine the strongest of all Softwoods
Image via Shutterstock
SYP scores highest of all softwoods in strength and durability, especially Longleaf and Slash Pines, which are only found along the South’s Coastal plain. These varieties make the best quality structural timber partly because they have long fibres and fewer knots, but also because they have a lot of resin. It is the resin that makes SYP so strong and Longleaf especially has higher resin levels than any other conifer.
Pine resin is a thick liquid produced by the tree to help protect it from damage and over time it sets hard as stone, making a ‘fossil resin’ you may know as amber. Longleaf timbers are often over 50% resin, so that when it sets solid the timber becomes heavy and hard.
Strength and Flexibility
The timber used should be properly graded and Machine Stress Rated (MSR), as this tests and guarantees the strength and resilience of the wood to the American Lumber Standards, it measures characteristics such as:
- Modulus of rupture (MOR), the strength or the maximum load carrying capacity of the wood.
- Modulus of Elasticity (MOE), the amount of bend in the wood or the amount of damage that is recoverable once the stress load is removed.
Southern Yellow Pine’s characteristics make it the strongest and best choice softwood structural timber because of its excellent load-bearing capacity (MOR of up to 112,000 kPa). But what makes SYP ideal for hurricane resistance is not just its strength, but also its flexibility (MOE of up to 13700 MPa), allowing the structure to bend and ‘give’ a little under high wind pressures without splitting under pressure from the high winds.
This is why SYP is the ideal wood for any storm resistant frame design, so if you have your heart set on a traditional wooden framed structure then go for it, just make sure it is built from Southern Yellow Pine. I guess no one told those three little pigs.
