Code-compliant 2X4 Walls for Zones Marine 4-8 - Code Notes

The 2009 International Residential Code and International Energy Conservation Code do not permit trade-offs for installing high-efficiency heating, ventilation, and air conditioning equipment—installing a 90%+ furnace as a trade-off for 2" x 4" stud walls with R-13 insulation. The more permanent building insulation and sealing features now take precedence. However, there still remain optional strategies allowing 2" x 4" exterior stud walls.