We have discussed on the previous page looking for wet insulation with an infra-red camera and with a nuclear gauge. Having one done on your roof periodically is not a bad idea as any wet insulation will tell you there are leaks. Some leaks are pinholes and don’t incur enough water to be noticeable from below but will do damage over time. This is especially true if your insulation absorbs water well (like fiberboard) and the water spreads sideways through the insulation instead of dropping through the nearest hole in the deck. Another technique for leak detection uses electricity. We have not seen this in action but hope to in the near future. This method seems to work best on roofs with metal decks and most waterproofing layers except EPDM (black rubber). The basic principle is to use water to conduct electricity. A wire loop is placed around an area, the area is wet down with a hose, and an electrical charge is generated through the wire. If there is a hole the electricity will follow the water down through the hole to the metal deck and change the electrical field, which can be measured and mapped with the proper equipment. This technique can be used on an existing roofing system or when re-roofing or newly roofing a building. During roof installation it is possible to embed a grid of wires or special tape in the roofing system and, generating a electric field, have a leak discovered by equipment when it occurs. The folks at Detec Systems tell us it is possible to monitor it over the Internet. We expect this technique to grow in the future as building owners and roofing specifiers are made aware of this technology. For more information on this check out these web sites (www.leak-detection.com and www.detecsystems.com).