• Moisture content in concrete

    Department of Finance, Building Management and Works (BMW) documentation reviews have found several instances where specifications state that: Maximum relative humidity of concrete: To AS 1884 Appendix A3.1.2 and A3.1.3 or the manufacturer’s recommendation. (0651 Resilient Finishes)

    However, if the manufacturer’s recommendation is a lesser standard than AS1884, the Superintendent’s Representative needs to confirm with the Principal if a lesser standard is acceptable.

    Government buildings must be designed and constructed in accordance with all relevant Australian Standards. AS 1884 requires that the relative humidity of a concrete floor should not exceed 75%.

    RH-probe

    BMW is aware that the manufacturer’s recommendations for some flooring products, such as adhesives, can allow a concrete moisture content that exceeds 75%. For BMW projects, the Lead Consultant or Super’s Rep must seek guidance from the Principal before approving a lesser standard than that required by AS 1884.

    In addition, BMW requires that all project specifications, and where applicable the Bill of Quantities, incorporate requirements to allow for slab and joint treatment, should moisture testing results fail to meet the required standard in AS 1884.

    For refurbishments to existing buildings, the specification should also allow for moisture barrier treatment to any existing slab area, including joints, that is to have new resilient flooring installed.

    For more information, see BMW's Technical Guideline - Moisture Content in Concrete Slabs.