Wind Resistant Buildings: Creating a Solid Design with ICF Blocks

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Wall systems constructed with Fox Blocks insulated concrete forms (ICFs ) ensure a wind-resistant structure with a strong continuous load path that holds the roof, walls, floors, and foundation together during an intense wind event. Fox Blocks also protect a structure and its occupants from projectile debris flying at over 100 mph during a strong storm.

The value of choosing Fox Blocks ICF construction was demonstrated in 2013, when a powerful EF5 tornado, with estimated speeds of 210 mph, attacked Moore, Oklahoma. The horrific wind event killed 24 and injured 212 people, wiping out most of the neighborhoods.

Left standing, however, was a ICF home built in 2004. For maximum protection against severe wind events, builders and architects are wise to choose Fox Blocks ICF construction.

The Importance of Wind-Resistant Design


A wind-resistant building design protects a structure and its occupants from strong winds and flying debris. Wind-resistant design is particularly important in hurricane- and tornado-prone regions.

A category one hurricane can destroy mobile homes. A category four hurricane, like Irma that hit the Florida Keys in 2017, can destroy wood-framed buildings and cause complete roof failure and wall collapse. A wind-resistant structure should remaining standing during and after severe wind events.

A wind-resistant building must also have the strength to stop flying debris from penetrating the wall system and threaten lives.

Essential Elements of Wind-Resistant Building Design

Wind-resistant construction is essential for protecting a building and its occupants from disastrous outcomes during strong wind events. Critical to wind-resistant building design is a continuous load path with strong roofs, walls, floors, and foundations, and impact resistance.

Continuous Load Path for Wind-Resistant Design

For wind-resistant building design, a continuous load path is the best protection against strong winds. A continuous load path ensures that when a load, including uplift and lateral (horizontal) loads, attacks a structure, the load will move from the roof, wall, and other parts, toward the foundation and into the ground.

A strong continuous load path is critical to holding the roof, walls, floors, and foundation together during a strong wind event of winds of over 200 mph.

Roof Construction of a Wind-Resistant Building


During high winds, building failures often begin with damage to the roof. A roof’s purpose, in a continuous load path, is to transfers the loads imposed by heavy winds to the supporting walls underneath. The roof sheathing works with the roof framing to transfer lateral loads to the structure’s shear walls.

For the protection of a building during a severe wind event, the building and sizing of the roof sheathing and framing must be in accordance with the wind forces of the region.

Roof Sheathing

FEMA’s Building Framing Systems and Best Practices approves the use of common nails to connect roof sheathing to supporting components in areas where wind speeds are less than 100 mph. Mandated in higher wind regions are ring-shank nails. Recommended in the corner zones eaves and the roof, where winds can cause large uplifts, are wood nails.

Roof Framing

After the roof sheathing, the roof framing is the next element found within the load path of a building. The roof framing transfers lateral loads to the shear walls. The rafters of a roof’s frame must be sized to resist the weight of the roof system, and also the loads caused by wind.

Floor Construction of a Wind-Resistant Building Design

The floor system is part of the continuous path that transfers the loads to the shear walls in the floors below or to the foundation. Floor framing typically consists of dimensional lumber, or floor joists, spanning an open area. Floor joists must be sized to resist the loads of the whole floor system along with vertical loads.

The floor of a wind-resistant building ensures the loads reach the foundation and ultimately the ground.

Impact Resistance of Wind-Resistant Design


During an intense wind event, flying debris is a constant threat to a building and its occupants. A best practice for protecting a structure and its occupants from flying debris are walls constructed with ICF. ICF provides greater resistance to damage from flying debris than wood-framed walls.

Buildings constructed with ICF walls protect the building and its occupants during extreme wind events of over 100 mph.

Fox Block ICF for Wind-Resistant Building Design

Buildings constructed with Fox Block ICF maintain their integrity during intense winds of over 200 mph and resist projectile debris moving over 100 mph.

Importantly, a report by the Portland Cement Association (PCA) concluded that ICF walls have greater structural capacity and stiffness to withstand the in-plane shear forces of high wind than wood- and steel-framed walls. Also, the strength of insulated concrete walls reduces the lateral twists and damage to non-structural elements.

Fox Blocks ICFs have the durability to withstand severe wind events and dangerous flying debris.

Wind-resistant building design must include a strong continuous load path that holds the roof, walls, floors, and foundation together and protects against flying debris during an intense wind event. A best practice for wind-resistant walls is building with Fox Blocks. Fox Blocks create wind-resistant walls that protect a building and its occupants from strong wind and flying debris.

Please visit Fox Blocks for more information on wind-resistant building design.