Thermal Benefits of Tiled Roofs with Above-sheathing Ventilation

Abstract

Computer simulations are conducted to demonstrate the thermal benefits of good roofing design in hot climates. The work is aimed to quantify the thermal benefits from batten-space ventilation, commonly referred to as above sheathing ventilation (ASV), and thermal mass. Both roof features are effective in reducing the heat transmission into the habitable space. Nevertheless, the use of roof ventilation is often misunderstood and most procedures for energy assessment of building structures do not recognize the contribution from ASV and thermal mass.

As part of this work, a computer algorithm is developed to predict the heat, air and moisture (HAM) transport in the building envelope. The algorithm predicts the transient temperature and moisture behavior in the building envelope and takes account of the air movement from bouyancy and wind driven airflows.

Keywords

energy HAM ventilation thermal mass.

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