Code changes are very complex, some take years for compliance and all are best left to discuss with your professional roofing contractor. Roofing codes are found in Chapter 15 of the International Building Code which is part of a family of codes from the International Code Council (ICC). Each of these codes are revised every three years before being promulgated. It is up to each state to decide which version of the code they wish to adopt and the adopted version may vary from state-to-state.
Brief summaries follow:
- Hot off the presses: Congress extended the 30% Investment Tax Credit (ITC) for solar and wind for three years. This legislation passed on 12/18/15 will extend the ITC for solar and wind for three years. Incrementally, it will decrease through 2021 and remain at 10% permanently in 2022.
- Minimum R-value requirements for various climate zones have increased. R-value is an insulating material's resistance to conductive heat flow measured or rated in terms of its thermal resistance. The higher the R-value, the greater the insulating effectiveness. The R-value depends on the type of insulation, its thickness, and its density.
- New requirements for the building envelope to include an air barrier to better manager air in- and ex-filtration. An adhered roofing system is “deemed to comply” with this requirement.
- FM Global continues to change the guidelines for enhancing existing steel deck attachments as they indicate that steel deck attachments are potential roof system weak points. By enforcing the enhanced steel deck attachments, it may add as much as 15% to the overall cost of the installed roofing system.
- Adhered systems that require a field uplift rating of 1-90 or greater are now being required to install a roof system that has been tested to the uplift requirements of the corner areas of a roof. This also translates into a much more costly roof installation for such jobs which are overwhelmingly located in hurricane-prone coastal areas.
- Wind design mandated code requirements for compliance will effect the cost of roofing. What this means to you is a roof that was formerly calculated to have a field uplift pressure of 60 psf will increase closer to 90 psf and the perimeter enhancements will be extended as well. This will also make roofs more expensive for compliance but they will perform better under high wind conditions.
- One other change that has increased roofing system costs is the change to the methodology for testing polyisocyanurate insulations Long Term Thermal Resistance (LTTR) R values. The new methodology for establishing the LTTR means that greater thickness of iso is now required to meet the IECC-mandated minimum R values.