Measurements reported in this paper demonstrate the increase in heat transfer due to convective air flow that can occur in wood-frame walls containing air-permeable mineral wool insulation with air spaces in contact with both sides. The effect of this air interchange between the air spaces increases with increasing temperature difference, air space height and air permeability of the insulation. Use of mid-height blocking and higher density insulation thus resulted in some reduction in the heat flow through the insulation, although convective effects were still significant.
Convective Air Flow Effects with Mineral Wool Insulation in Wood-Frame Walls
Building Services Section, NRCC, Ottawa, Canada, ASHRAE Trans., Vol No 72, ASHRAE