How to Design & Construct a House to Withstand 150 MPH Wind

• Foundation size (e.g., footing width, pile embedment depth, number of piles) depends partly on dead load.
• Dead load counterbalances uplift forces due to buoyancy and wind.
• Dead load counterbalances wind and earthquake overturning moments.
• Dead load changes the response of the building to both seismic forces and impact forces generated by floating objects.

• Foundation size (e.g., footing width, pile embedment depth, number of piles) depends partly on dead load.
• Those from non-breaking waves (these forces can usually be computed as hydrostatic forces against walls and hydrodynamic forces against piles)
• Those from breaking waves (these forces will be of short duration, but large magnitude)
• Those from broken waves (these forces are similar to hydrodynamic forces caused by flowing or surging
  water)
• Uplift (these forces are often caused by wave run-up, deflection, or peaking against the underside of horizontal surfaces)

Of these, the forces from breaking waves are the highest and produce the most severe loads. Therefore, this manual strongly recommends that the breaking wave load be used as the design wave load.

• Determining design loads
• Determining the building’s foundation, structural frame, and envelope
• Determining the connections between individual elements
• Determining the elevation, placement, and support for utilities
• Selecting the appropriate materials

The entire design process is based on the fundamental premise that anticipated service and natural hazard loads can and must be transferred through the building in a continuous path to the supporting soils. ANY weakness in that continuous path is a potential point of failure of the building, and any failure creates the possibility for large property losses and the potential for loss of life.

• dead loads
• live loads
• flood loads
• wind loads
• earthquake (seismic) loads
• snow loads

• All design loads create forces in and on the building. The forces are transferred through load paths.
• Load paths always end in the soil that supports the structure.
• Loads should be applied to the building beginning at the top.
• Loads should be determined for both the vertical and horizontal load paths.
• Load transfer creates forces at connections and imparts stresses materials. Connections and materials must be strong enough to those forces and stresses.
• The load path must be continuous; any break or weakness in the path “chain” can result in damage or even structural failure.

• Uplift: Vertical forces caused by wind or buoyancy exceed the weight of the structure and the strength of the soil anchorage. The building fails by being lifted off its foundation or because the foundation pulls out of the soil.
• Overturning: The applied moments caused by wind, wave, earthquake, and buoyancy forces exceed the resisting moments of the building’s weight and anchorage. The building fails by rotating off its foundation or because the foundation rotates out of the soil.
• Sliding or Shearing: Horizontal forces exceed the friction force or strength of the foundation. The building fails by sliding off its foundation, by shear failure of components transferring loads to its foundation, or by the foundation sliding.

• Piles, piers, or columns must be properly aligned.
• The piles, piers, or columns must be driven or placed at the proper elevation to resist failure and must extend below the expected depth of scour and erosion.
• Foundation materials must be flood damage-resistant (pressure treated wood, masonry, concrete).
• Provide adequate support at the top of the foundation element to properly attach the floor framing system. Do not notch a wood foundation element more than 50 percent of its cross-sectional area.
• Breakaway walls are intended to fail; do not overnail these walls to the foundations; do not install utilities or other obstructions behind these walls; do not finish inside these walls.
• Where foundation elements are masonry or concrete (except slabson-grade), place the proper size of reinforcing, the proper number of steel bars, and provide the proper concrete cover over the steel.
• Exposed steel in the foundation will corrode; plan for it by installing hot-dipped galvanized or stainless steel.
• Areas of pressure-treated wood that have been cut or drilled will retain water and will decay; treat these cut areas in the field.

• Store firewood and other wood items, including wood mulch, on the ground, away from the building.
• Keep gutters and downspouts in good repair and positioned to direct water away from the building.
• Keep water pipes, water fixtures, and drainpipes in good repair.
• Avoid dampness in crawlspaces by providing adequate ventilation or installing impervious ground cover membranes.
• Avoid frequent plant watering adjacent to the house, and keep plants trimmed away from the walls.

• Fading of finishes
• Accelerated checking and splitting of wood
• Gradual loss of thickness of wood