Building sheet and method for detecting weatherproofness of structures

摘要

A building sheet which changes a detectable visual characteristic of the sheet when exposed to certain environmental conditions. In a preferred embodiment a hydrochromatic layer is applied to a building sheet and a change in colour or transparency may be detected visually to indicate exposure to water. Use of such a building sheet in a building enables detection of a fault before a structure is enclosed. The building sheet may be formed by applying a detection composition to one or both sides of the sheet in continuous layers or in a desired pattern.