We relate experiments carried out both in the lab, in a guarded hot box, and in experimental test houses. It is shown that forced convection does not significantly affect the thermal properties of the insulation under the air velocities usually found in the cavities, unless the construction mode and/or workmanship allow multiple air entry zones, or discontinuities in the insulation or in the internal air barrier.

A computer model was also developed to help us understand the convective flow patterns inside the porous insulation, as induced by the forced convection above it. A fairly good agreement with experimental results could be obtained.