The lift coefficient for concrete and clay tile is stated as which value?

The lift coefficient for concrete and clay tile is stated as which value?

• A. 0.15
• B. 0.18
• C. 0.20
• D. 0.25

Answer: (C)

The lift coefficient tells you how much wind uplift a roof covering experiences per unit of wind pressure. For concrete and clay tile, the standard value used in Florida practice is 0.20, meaning the uplift force per unit area is 0.20 times the dynamic wind pressure (q). Put simply, if the dynamic pressure on the roof is known, multiply it by 0.20 to get the uplift per square foot that the tile system must resist. For example, if q equals 100 psf, the uplift would be 20 psf. This 0.20 reflects the balance of tile weight and interlocking that gives tiles notable resistance to uplift while still requiring proper fastening.

The lift coefficient tells you how much wind uplift a roof covering experiences per unit of wind pressure. For concrete and clay tile, the standard value used in Florida practice is 0.20, meaning the uplift force per unit area is 0.20 times the dynamic wind pressure (q). Put simply, if the dynamic pressure on the roof is known, multiply it by 0.20 to get the uplift per square foot that the tile system must resist. For example, if q equals 100 psf, the uplift would be 20 psf. This 0.20 reflects the balance of tile weight and interlocking that gives tiles notable resistance to uplift while still requiring proper fastening.