Characteristics of internal and external pressures and peak net pressures on a building envelope

Abstract

Net pressures on roofs and walls of a building are dependent on the internal and external pressure fluctuations. The internal pressure is influenced by the sizes and locations of the openings in the building envelope. The peak net pressure (Cp∨,net) for cladding design on the roof and walls of a building will depend on the internal and external pressure fluctuations and their correlation.External and internal pressure fluctuations and their correlations measured on the roof and wall of a 1:200 scale model nominally permeable building and a building with a wall opening were used derive peak net pressures. The large external suction pressures and the small internal pressures in the permeable building are positively correlated whilst the large external suction pressures and the large positive internal pressures in the building with windward wall opening are negatively correlated. Widely available basic statistical properties of external and internal pressures (i.e. mean, standard deviation, and peak coefficients) and their correlations are applied with the fundamental theory of the covariance integration method (without the need for their time histories) to satisfactorily estimate the peak net design pressure to within 10% of the measured value.