DIMENSION STONE AND TWENTIETH CENTURY BUILT HERITAGE; DURABILITY EVALUATION USING REGIONAL COMPARISONS OF CLIMATIC DATA

This paper presents a review and analysis of climatic conditions for the assessment of durability in dimension stone used in the construction of twentieth century built heritage. The analysis includes a survey of climatic conditions in several North American and European cities that could be utilized when comparing weathering characteristics across similar stones in different environments. Weathering data reviewed includes temperature extremes, precipitation, acid rain, freeze-thaw cycles, and freezing after a saturating rain. This weathering data reviewed can be useful when evaluating stone for both building facades and construction of built heritage that span the twentieth century. This information may also be practical in predicting the weathering effects of a previously used stone proposed for use in a new environment. The number of freeze thaw cycles found by others to cause damage to stone in laboratory accelerated weathering testing is shown to correlate to certain environmental conditions. A weathering index for stone is proposed as a way to quickly compare certain environmental factors between cities and this affects durability of dimension stone used in construction of built heritage across the last century.