Wind storms are causing economic losses to grow around the world. Surveys have indicated that a proportion of the damage is due to failures of the building envelope and connections, e.g., cladding failures caused by net pressure loads or wind-borne debris impacts, failures of nailed connections, etc. Cladding and connection design tends to rely on significant simplifications. The performance of building products, is usually evaluated in standardized tests that require the application of static and uniform pressures to a portion of the cladding system place in a pressure chamber. While such applied loading is consistent with the design loads, it is well known that real wind loads have variability both in space in time, with spatial and temporal pressure gradients over all building surfaces. The objective of this paper is to examine the effects and the response of both pressure gradients on both the wind loading acting on various aspects of cladding systems. The multi-chamber, pressure loading approach will be used as the primary tool, along with boundary layer wind tunnel test data and numerical models of multi-layer, air-permeable cladding and single-layer cladding systems. In terms of spatial gradients, the paper will include analysis of area-averaging effects for statically-indeterminant systems with load sharing between fasteners, and pressure equalization within multi-layer systems and the concept of design pressure gradients. In terms of temporal gradients, the role of the rate of pressure change in these non-resonant systems is examined, along with the role of duration of high loads and gust duration.