Last Updated 6/10/2020
  FORTIFIED™ Wind Uplift Design Pressure Calculator for Residential
Steep-Slope (2:12 or Greater) Roof Coverings1,2,3
      Mean Roof Height (ft) =
      Roof Slope =
       Design Wind Speed, Vult (mph) =
      Exposure = 
        Wind Uplift Design Pressures (psf):             
        Refer to FORTIFIED Standard Detail F-G-2
below for locations of Zones 1,2,&3
  1. Wind uplift design pressures provided are Component and Cladding (C&C) ASD pressures acting away from the roof surface per ASCE 7-10 Figure 30.5-1 and 2015 IRC Table R301.2(2). Minimum pressures for FORTIFIED correspond to Vult = 130 mph with Exposure C.  
  2. This design aid is intended to be preliminary guidance for section R905.1 of 2015 IRC for use with the FORTIFIED Home Program. Design pressures must meet or exceed local code requirements. This aid does not supplant the need for drawings or plans to be reviewed and signed by a professional engineer.  
  3.  Understanding design pressures is critical to selecting and installing roofing materials to comply with the IRC and the FORTIFIED Home program. Refer to FORTIFIED Technical Bulletin FH 2020-01 for additional guidance.