Uplift – Tree of Life and Associates

Wind Uplift Resistance

Tree of Life and Associates (TOL) has performed extensive analyses and lab tests on uplift resistant pedestal-paver systems to determine the effects of wind on raised terrace applications at Miami-Dade certified testing labs. The TOL-tested paver-pedestal terrace system provides up to -455 psf (avg. pounds per square foot) of uplift resistance. Applying an engineering factor of 2:1, our system is certified for -227.5 psf. Thus, our technology achieves higher resistance than the uplift pressures generated by Cat-5 hurricane winds, which are commonly calculated at –170 psf in 10-story buildings in coastal areas following industry standard guidelines as provided by ASCE 7 (Associated Criteria for Buildings and Other Structures, ASCE/SEI 7-22) and Chapter 16 of Florida Building Code (High Velocity Hurricane Zones), including Miami-Dade County. Request information from our sales associate.

How Wind Uplift can affect a building’s roof

Wind Forces
A building is an obstruction to wind flow and causes a change in the direction of airflow and pressure over a building’s surface. Consequently, wind damage may occur indirectly from the impact of wind-borne debris or directly through the pressure it exerts.

Generally, the direction of airflow corresponds to pressure in the following ways:

Positive pressure occurs on windward surfaces.
Negative pressure occurs on leeward surfaces.
Negative pressure occurs at sharp discontinuities (eaves, corners, and rakes).
NOTE: The presence of openings to the building’s interior also affects the roof. As air infiltrates through openings and cracks, the internal air pressure increases. This ranges from slightly elevated air pressure caused by HVAC equipment, for example, to strongly elevated air pressure caused by strong thunderstorm winds entering window and door openings.

Wind uplift is a force measured in pounds per square foot (psf). It occurs when the pressure below the roof is greater than the pressure above. This can be intensified during high winds, as air infiltrates into the building, causing an increase in air pressure below the roof, while the speed of the wind over the roof reduces the air pressure above it. When wind uplift is greater than what the building system was designed for, and in the worst-case scenario, the roof deck could potentially detach from the supporting structure. This is more common if the roof deck has open joints, unlike cast-in-place roof decks. However, engineers and building designers follow strict codes and guidelines to prevent this, which vary by building location and likelihood of exposure to high winds.