| 摘要 |
<p>A wide gap is formed in the main roof or between the main roofs 4, 5 of a building such as a cattle shed or barn, and a sub-roof 6 is formed below the wide gap and at a level below that the main roof(s) to form at least one large ventilation opening 7 between the roof or roofs and the sub-roof from beneath the roofs to the wide gap. The main roof or roofs overlap the sub-roof 6 so that the weather shelter integrity of the roof is preserved. The sub-roof may be raised or lowered to vary the ventilation area 7. The top surface of the sub-roof is a low albedo surface to receive and absorb solar radiation and heat the air above the sub-roof to amplify a convection current of warm air rising off the sub-roof which in turn creates a flow of cooler air through the living spaces 1, 2 of the building from the sides of the building and through the ventilation openings 7. Partially permeable barriers 8 may be raised or lowered into the ventilation openings to control the flow of air through the ventilation openings according to ventilation requirements.</p> |
