Rationale

Updates to Section 5.1.2.1 were previously balloted under work item WK90100. Several negative ballots raised concerns related to realistic drying times with modern construction schedules, importance of moisture content as it relates to the curing of concrete and masonry materials, and concerns related to the use of computer simulations when real world data is available. The underlying concern that drove WK90100 is still considered valid, that modern construction practices, and the incorporation of air barriers and vapor retarding materials, coupled with desired improvements to energy efficiency (thus often a reduced mechanical drying potential) necessitates the consideration of initial moisture in all materials not just wood framing. This work item proposes to modify the language of Section 5.1.2.1 of standard E241, to acknowledge that initial moisture of all materials must be considered, not just wood walls. The changes are being presented in the context of Section 5 in its entirety to provide voters an opportunity to review the overall discussion related to sources of moisture and proposed changes. Consideration will be given in the task group as to whether Section 5.1.2.1 should be moved to Section 5.4. Additional modifications to Section 5 may be required and will be addressed as separate work items. This work item is limited to the updates to Section 5, in particular the language of Section 5.1.2.1 and the most appropriate location of Section 5.1.2.1 within Section 5, to limit the potential misinterpretation that initial moisture content within materials is limited to wood framed walls.