Abstract

Polyurethane waterproofing membranes are constructed at building sites by applying liquid material to substrate. The membrane thickness is related to the durability of the waterproof material, so quality control during construction is important. However, the membrane thickness is likely to be unstable because it is affected by various factors, such as the environment, substrate conditions, method of waterproofing material application, and construction skills. Therefore, a reduction in thickness variation is extremely important to secure the quality of the waterproofing membrane. To examine which construction conditions can ensure a uniform and appropriate thickness, we examined the combination of allocation method of the suitable construction area and application tools as an example of process control during construction. The construction area width and length were important, and a comparatively uniform and appropriate thickness could be ensured, when construction was carried out over an area with a 1.4-m width and length of 5.15 m by using the trowel and squeegee.