Air infiltration through cracks in suspended timber floors

Abstract

Although the power law equation may be used to correlate air flow rate to the pressure difference across a tongue-and-groove floor, the relationship between the coefficient and exponent and the physical parameters of the crack remains concealed to research. Moreover, the pressure loss through the cracks between floorboards of an in-situ floor is reasonably described by the empirical equation for cracks with known dimensions. This is ΔP = AQ + BQ ² for pressure differences of 0-50 pascals, although the recorded data is for 2-50 pascals. The present results lend support to the published expression for the determination of the theoretical edge effect constant B. However more work is needed in the area of laminar flow through very small, contorted cracks and in the assessment of the crack length. Finally, it is suggested that crackage between floorboards is due to the nature of materials and practices in the construction industry.