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Exceed code-required insulation levels in the roof

Tags: Add a floor above, Kitchen or bath addition, New construction, Gable or eave end add-on, Gut rehab, Home performance & weatherization, Gut rehab, Home performance and weatherization, roofs, cold, dry, hot_humid, Insulation, marine, mixed_humid

Roof insulation is key to saving energy
Roofs are exposed to more direct solar radiation during the summer than walls, so effective insulation there is important for reducing cooling loads. In wood-frame buildings insulating is relatively easy and inexpensive because the rafters or trusses are usually deep enough to hold plenty of fiberglass or cellulose insulationThermal insulation made from recycled newspaper or other wastepaper; often treated with borates for fire and insect protection.. The 2009 energy code calls for R-values in the roof ranging from 30 to 49, depending on climate zone. Although meeting these insulation levels is clearly a good idea, beating them is better.

Code Minimums:
Zones 1-3: R 30
Zones 4&5: R-38
Zones 6-8: R-49

Green points

LEED for HomesLeadership in Energy and Environmental Design. LEED for Homes is the residential green building program from the United States Green Building Council (USGBC). While this program is primarily designed for and applicable to new home projects, major gut rehabs can qualify. : 2 points for enhanced insulation (EA 2)
NGBSNational Green Building Standard Based on the NAHB Model Green Home Building Guidelines and passed through ANSI. This standard can be applied to both new homes, remodeling projects, and additions. /ICC-700: Up to 36 points for exceeding energy code requirements on total building envelopeExterior components of a house that provide protection from colder (and warmer) outdoor temperatures and precipitation; includes the house foundation, framed exterior walls, roof or ceiling, and insulation, and air sealing materials. thermal performance, depending on climate zone (703.1).