Catch household water leaks as soon as they happen with this inexpensive alarm. Avoid structural damage or the growth of harmful mold.

Hacked from a $1 battery-powered window/door alarm from Dollar Tree Inc., I replaced the magnetic sensor with electrodes (two pennies) to sound the alarm when the pennies get wet. Small enough to be placed unobtrusively anywhere water may puddle, these devices are ideal for monitoring common household trouble spots such as hot water heaters, air handlers, water shut-off valve stems, HVAC hoses, washing machines, household plumbing, kitchen and bathroom sinks, bathtubs and jacuzzis, sweating pipes, basement sumps and drains, ingress from rain, snow or ice or anywhere signs of prior water damage is evident. At approximately 90 decibels, the warbling alarm signal lets you know when a leak has been detected. Includes an on/off switch. The unit includes three LR44 alkaline batteries which should last approximately two years.