Summary of Corps of Engineers Research on Roof Mositure Detection and the Thermal Resistance of Wet Insulation.
Abstract
Nuclear, infrared, capacitance, microwave and impulse radar methods for nondestructively detecting moisture in roofs were evaluated. No system was reliable enough by itself or by cross-checking with another system to eliminate the need for a few core samples of membrane and insulation to verify findings. Airborne infrared surveys are a cost-effective way of reconnoitering numerous roofs at a major installation. However, follow-up on-the-roof surveys are necessary. Of the several grid techniques examined, nuclear surveys were the most reliable. Hand-held infrared surveys are the most accurate on-the-roof method studied. Although an infrared camera costs significantly more than a nuclear meter ($27,000 vs $3,000), infrared surveys can be conducted more rapidly. Where numerous roofs are to be surveyed, infrared surveys appear to be the most cost-effective method. In-situ measurements have been made of the thermal resistance of wet and dry portions of roofs. A laboratory apparatus has been built to subject 12 in. x 12 in. specimens of roof insulation to combined thermal and moisture gradients. Thermal resistance and mositure content are periodically determined and characteristic curves are being developed for various roof insulations. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1978
- Accession Number
- ADA063144
Entities
People
- Charles Korhonen
- Wayne Tobiasson
Organizations
- Cold Regions Research and Engineering Laboratory