Building exterior paint performance in tropical salty environment of Lagos

Abstract

Materials that are used for exterior finishes of buildings are their last line of defence against the elements of climate. The compliance of the materials with the environment will determine their performance and consequent repainting. A high percentage of buildings? exterior surfaces are finished with paint in Lagos in the south-western region of Nigeria that has additional climatic stress of saline air from the Atlantic Ocean. This research examines the factors that influence the use of paint and the occurrence of salt impact indicators as parameters for measuring its performance in Lagos, Nigeria, in order to determine the repainting requirement when applied as exterior finish. A mixed approach of qualitative and quantitative methods was used. Survey was done to collect data for the analysis. The study area was bifurcated into two zones (Zone A & B) in order to compare the performance of painted exterior of the buildings along the coast with the hinterland. After exhaustive literature search, variables identified were used to investigate the phenomenon. While some variables were measured using Likert?s scale, some were simply measured through categorical and continuous scales. A total of 317 questionnaires were returned out of the 384 sample size of the first target population. Guided interview was conducted on sixteen (16) architects and six (6) paint manufacturers provided information on salt resistant paint of the second and third target population respectively. Various appropriate statistical models were used with the significance level set at p<0.05 in processing the data to obtain results for inferences. Findings show that the choice and usage of paint as exterior finish for buildings in the study area depend on experience, professional advice, availability, cost, societal influence and cultural values. The performance and climatic compliance are jettisoned because of cultural attachment to colour that paints make available with relative ease. All salt impact indicators appeared earlier in Zone A than Zone B. These also necessitate earlier and frequent repainting in Zone A. The number of years required for repainting in Zone A and Zone B are 2 and 4 years respectively compared with 5-7 years established in past researches as required for repainting in other parts of the tropical region. The outcome of the research facilitates maintenance forecast and schedule for painted exterior in the tropics.