To improve the air-permeability and heat insulating properties of a panel arranged between aggregates of a wooden house by providing ventilation holes communicating with a prescribed void provided between a flat plate and a heat insulating material in a frame given the flat plate on one side thereof.

A flat plate 3 such as plywood is joined to one side of a frame 1 provided with a reinforcing member 5 formed by connecting four squares with nails, and a panel 20 is made up by providing a heat insulating material 2 inside the frame 1 leaving only one end so that it may have a prescribed void 9 with the flat plate 3 and it may make a hole 6 and the void 9 communicate with each other. The panel 20 is mounted in a space surrounded by aggregates such as a purlin, eaves timber, pole plate and rafter with the side having an air hole 4 on the ridge side and the hole 6 on the eaves side, the insulating material 2 may be inside a house. Therefore, the air-permeability of a house improves, dew condensation, corrosion of wooden materials can be prevented. Furthermore, a house that is cool in summer and warm in winter can be built easily and in a short time.