Subgrades and Vapor Barriers vs Moisture Science Fair Projects

Moisture Barriers

Moisture barriers are used to prevent moisture that is found in specific areas of a home from damaging building materials. Common places to find there barriers are in the bathroom, laundry room and basement.

Objectives/Goals

This continuation project progresses from examining the effects that subgrades and vapor barriers have on concrete moisture emissions; in order to study vapor pressures, which will allow us to observe the limitations of moisture testing equipment including calcium chloride testing kits.

Methods/Materials

Our research has shown us that moisture floor covering problems still occur on concrete slabs even when calcium chloride testing has been used to indicate the concrete is dry enough to accept a floor covering. This project investigates the role water vapor pressure plays on moisture migration, utilizing data loggers to record temperature, humidity, and dew point above and below the concrete samples. We exposed the test samples to different variations of heat using insulation boxes that we made.

Results

Test samples were exposed to sunlight in the testing dome when the concrete was dry and their change in humidity was 6%. When they were exposed to sunlight below the concrete the results were similar. Furthermore, when the concrete samples were wet relative humidities, when exposed to sunlight in the testing dome, decreased by 5%. When they were exposed to sunlight below the concrete the results were similar. However, the calcium chloride test kits became saturated when the wet concrete samples were exposed to sunlight in the testing dome, but the test kits did not become saturated when the buckets below the concrete samples were exposed to sunlight.

Conclusions/Discussion

Our results meant that calcium chloride kit results are affected by environmental changes because relative humidities were staying stable, but calcium chloride test kit results were varying wildly when the buckets were exposed to varied environmental conditions. The results of this experiment will assist in modifying moisture migration test procedures to insure that results will become a more accurate measure of moisture migration. 3rd party contributor