A new thermal performance index for dwelling roofs in the warm humid tropics

Chitrarekha Kabre

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

This research aims to find a scientific rating scheme for roof system for the warm humid tropics. The overall air-to-air thermal transmittance (U-value) or thermal resistance (R-value) of roof are most widely used properties, but these are based on steady-state heat conduction and do not respond to changing conditions of climate, design and comfort needs. The paper presents a new thermal performance index, which is based on thermal comfort and actual thermal performance of a roof design option. It provides a basis for identifying the optimum roof design for unconditioned and acclimatised regimes. A review of the acceptable limits of ceiling surface temperature is presented. The mathematical modelling for predicting performance of roof based on admittance procedure and derivation of thermal performance index is described. In the proposed scheme the galvanized iron roof is given 0% rating and the roof satisfying the comfort needs for the given climate is rated as 100%. Illustrative examples of built roofs or design options are taken from India and Australia. It clearly shows that the roofs with the highest thermal resistance are not necessarily optimum solutions.

Original languageEnglish
Pages (from-to)727-738
Number of pages12
JournalBuilding and Environment
Volume45
Issue number3
DOIs
Publication statusPublished - 01-03-2010
Externally publishedYes

Fingerprint

Tropics
humid tropics
tropics
Roofs
roof
performance
rating
air
climate
mathematical modeling
heat
Heat resistance
Values
regime
India
Hot Temperature
dwelling
index
Thermal comfort
transmittance

All Science Journal Classification (ASJC) codes

  • Environmental Engineering
  • Civil and Structural Engineering
  • Geography, Planning and Development
  • Building and Construction

Cite this

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A new thermal performance index for dwelling roofs in the warm humid tropics. / Kabre, Chitrarekha.

In: Building and Environment, Vol. 45, No. 3, 01.03.2010, p. 727-738.

Research output: Contribution to journalArticle

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