Taiwan is located within a subtropical region where the preservation of tracing paper is challenging, given its susceptibility to changes in humidity. Although the National Archives Administration (NAA) currently provides a controlled environment for the repositories of the National Archive, this archive has sustained damage and deterioration due to a legacy of compromised storage and inherent fragility of its contents. Of particular interest are the collective holdings of the Taiwan Railways Administration (TRA), the Ministry of Transportation and Communications (MOTC). Historically, these holdings were originally known as ‘The Railway Department of the Traffic Bureau, under the General Governor of Taiwan’, during Japanese colonial governance. This specific collection dates from 1895 to 1997 and includes over 10,000 engineering drawings. Previously, the NAA had implemented linings to both repair damage and aid in the preservation of the physical archives. However, this study compares this approach with an alternative humidification method using Gore-Tex® to relax and flatten these drawings on tracing paper. The focus of this paper is to evaluate dimensional change as a result of these treatments and to make recommendations in regards to their respective suitability for addressing the condition of the TRA collection.