SpecTips - ASCE7 v. DORA
Understand the New Listing Program from IBC
The Directory of Roof Assemblies (DORA) is the newest listing program for International Building Code (IBC) Chapter 15-compliant roofing assemblies. This web-based directory is free to use and is available to any user, including specifiers, architects, consultants, building owners, contractors, and manufacturers. DORA provides listings for assemblies in accordance with wind uplift designs. You can search for tested assemblies by uplift requirements as determined by ASCE 7 calculations if desired.
To meet the IBC-required uplift pressures associated with the roofing assemblies, uplift pressures must be calculated in pounds per square foot (psf) and verified by testing.
The determination of the uplift should be completed by the designer of record or through his/her licensed engineer using ASCE 7. Once accomplished, manufacturers can confirm the assembly’s compliance through uplift rating records.
The use of ASCE 7 is based on the adoption of the IBC, either statewide or locally.
TIPS
To assist, CCM Sales Representatives have access to ASCE 7 calculators and can provide uplift pressures.
Once these pressures have been determined, it must be certified that the specified roof assembly has been tested following ANSI/FM 4474 in psf. These records are then listed on the DORA website.
PROCESS SUMMARY
Here’s how simple it is to determine the correct roofing assembly for a specific building to meet the IBC: Determine the building’s uplift pressure using the ASCE 7 calculations, which should be completed by a locally licensed or qualified design professional. Review the roofing assembly’s “reported pressure”, which is collected from manufacturers’ results and ratings from ANSI/FM 4474 and listed on the DORA website. Compare and verify the DORA listed pressures, which need to be equal or greater than the ASCE 7 pressures. Once the assembly has been selected and confirmed to meet the uplift pressures, it’s important to read and carefully consider warranties to confirm that the wind coverage meets the building owner’s needs and is easily understood. Keep in mind, when higher wind speed coverage is requested from the material manufacturer, additional enhancement may be necessary to qualify for the warranty. This may require additional enhancements, which will likely increase the cost of the total assembly and may increase the cost of the warranty.
The Directory of Roof Assemblies (DORA) is the newest listing program for International Building Code (IBC) Chapter 15-compliant roofing assemblies. This web-based directory is free to use and is available to any user, including specifiers, architects, consultants, building owners, contractors, and manufacturers. DORA provides listings for assemblies in accordance with wind uplift designs. You can search for tested assemblies by uplift requirements as determined by ASCE 7 calculations if desired.
To meet the IBC-required uplift pressures associated with the roofing assemblies, uplift pressures must be calculated in pounds per square foot (psf) and verified by testing.
The determination of the uplift should be completed by the designer of record or through his/her licensed engineer using ASCE 7. Once accomplished, manufacturers can confirm the assembly’s compliance through uplift rating records.
The use of ASCE 7 is based on the adoption of the IBC, either statewide or locally.
| IBC Edition | ASCE 7 Edition |
| 2018 | 2016 |
| 2012 and 2015 | 2010 |
| 2003, 2006, and 2009 | 2002-2005 |
To assist, CCM Sales Representatives have access to ASCE 7 calculators and can provide uplift pressures.
Once these pressures have been determined, it must be certified that the specified roof assembly has been tested following ANSI/FM 4474 in psf. These records are then listed on the DORA website.
PROCESS SUMMARY
Here’s how simple it is to determine the correct roofing assembly for a specific building to meet the IBC: Determine the building’s uplift pressure using the ASCE 7 calculations, which should be completed by a locally licensed or qualified design professional. Review the roofing assembly’s “reported pressure”, which is collected from manufacturers’ results and ratings from ANSI/FM 4474 and listed on the DORA website. Compare and verify the DORA listed pressures, which need to be equal or greater than the ASCE 7 pressures. Once the assembly has been selected and confirmed to meet the uplift pressures, it’s important to read and carefully consider warranties to confirm that the wind coverage meets the building owner’s needs and is easily understood. Keep in mind, when higher wind speed coverage is requested from the material manufacturer, additional enhancement may be necessary to qualify for the warranty. This may require additional enhancements, which will likely increase the cost of the total assembly and may increase the cost of the warranty.
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