Abstract: The present invention comprises an article and a method of preventing undesired wind and moisture encroachment into the space between adjacent joists and rafters of a building. The method includes the steps of: providing an elongated flexible web article having a foraminous elongated first side edge portion and a pair of elongated, wind-impermeable, second sides co-extensive and co-attached with said first side portion; attaching the first foraminous long side to the rafters; cutting a portion of the wind-permeable material and the second wind impermeable sides on the rafters; draping the flaps now defining the cut first and second sides of the elongated web down between the joists; and securing the lower end of one flap to the vertical outside wall, and pulling the remaining second side flap back over the insulation between the rafters, to provide an eave block, vent and channel arrangement between the joists and to permit controlled ventilation between the rafters.