AN EVALUATION OF BUILDING HEIGHT EFFECTS ON THERMAL COMFORT IN HIGH-RISE OFFICE BUILDINGS IN THE TROPICAL ENVIRONMENT

PROPOSED TITLE OF THESIS                                          An Evaluation Of Building Height Effects On Thermal Comfort in High-rise Office Buildings in the Tropical Environment

SYNOPSIS

INTRODUCTION

Nigeria as a developing economy situated in the tropical climate zone is faced with a number of economic and environmental challenges when it comes to the development of her housing sector. High-rise buildings provide a borrowed but welcome solution to some of these challenges but however must be adapted to suit our own climate and weather conditions. The problem this study is concerned with solving is that of thermal discomfort experienced in high-rise office buildings in the hot humid tropical environment mostly due to arbitrary transfer of western Architectural styles. This study aims to evaluate the possible influence of increase in building height on indoor thermal comfort in high-rise office buildings in the study area with a view to understand the behaviour of high-rise buildings in our climate and thus provide guidelines for the future design of such buildings in the tropical area. The research gap this study intends to fill is easily observed in the plethora of literature from research works addressing related issues like thermal comfort in low-rise office and residential buildings, building height effects on outdoor thermal comfort of a city, but none has actually addressed the possible effects of increase in building height on indoor thermal comfort in high-rise office buildings within the tropical environment. The objectives to aid the achievement of the aim above include: Survey of existing high-rise office buildings in the study area and their constructed heights, empirical assessment of indoor thermal comfort in the sample high-rise buildings at different floor levels during working hours, qualitative assessment of indoor thermal comfort in the sample high rise buildings at different floor levels during working hours, use of statistical analysis tools to compare results from the empirical and qualitative assessments and statistical analysis of experimental results to establish significant relationship(s) between building height and indoor thermal comfort (if any).

METHODOLOGY

This work is a co-relational / survey research study concerned with the collection of data with the aim to clarify patterns of relationships between two or more variables. The area of the study is the central business district, CBD Abuja. The population comprises of all the high-rise office buildings within the study area. To determine the sample size for this study, the Taro Yamani formula will be used. The predicted mean vote (PMV) model for thermal comfort calculation will be employed. Empirical readings from hand-held measurement instruments for air temperature, air velocity, atmospheric humidity, mean radiant temperature, clothing level and body metabolic rate will be evaluated using the CBE Thermal Comfort Tool for ASHRAE 55. A structured questionnaire will be administered to the building users to assess their subjective perception of thermal comfort at the different floor heights. The reliability of the instrument will be established using test re-test method and Cronbach’s Alpha will be used to establish the coefficient of reliability of their responses. Statistical correlation between the measured data on thermal comfort and the building height will be tested using measures of correlation.

EXPECTED RESULTS

The result from the calculation of thermal comfort and that from the response of the building users will be compared and are expected to be similar. The result from the tests for statistical correlation between increase in building height and the thermal comfort will serve to prove or disprove the research hypotheses.