The purpose of this test is to obtain steady state values of water vapor transfer through the EIFS sample. This characteristic of EIFS is commonly requested by regulatory and design organizations, and is used in thermal and moisture studies of building walls. The degree to which an EIFS allows water vapor to pass through it can affect the performance of an EIFS wall assembly.

A permeance value obtained under one set of test conditions does not indicate the value under a different set of conditions. For this reason, the test conditions selected are those that most closely approach the conditions of use for EIFS components and assemblies.

This standard should not be used alone as the sole means for evaluating the water vapor transmission characteristics of a given EIFS wall assembly. Other methods are available, and should be considered and used as appropriate.

To be meaningful in evaluating the thermal and moisture condition of a given EIFS wall assembly, the specimens used in this standard should represent closely the materials that actually exist, or will exist, on a given building.

1.1 This standard describes how to use Test Methods E 96 to determine the water vapor transmission (WVT) characteristics of an EIFS sample.

1.2 An Exterior Insulation and Finish System (EIFS) is a multilayer exterior building wall material that consists of a number of layers. For the purpose of this standard, these layers, whether they be individual EIFS component materials in single layers, or groups of EIFS component materials, are called the "EIFS sample."

1.3 The Water Method, Procedures B and D described in section X1.1.2 and X1.1.5 of Appendix X1 of Test Methods E 96 shall be used in this standard.

1.4 This standard is limited to specimens not over 11/4 in. (32 mm) in thickness, except as provided in Section 9 of this standard.

1.5 The values stated in inch-pound units are to be regarded as the standard. Metric inch-pound conversion factors for water vapor transmission, permeance, and permeability are stated in Table 1 of Test Methods E 96. All conversions of mm Hg to Pa are made at a temperature of 0°C.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.