After doing our HB renovation an adding a side by side with ice maker. I decided to purchase 4-5 first alert water detectors. Was very impressed with the sensitivity of the unit's. The actual contacts it uses has to come in direct contact with water to complete the circuit to activate the alarm. (sounds same as a common smoke detector same db).
so its a target related alarm you need the water to activate it, thus the Tip. obviously you will place the lead, where you think the water is likely accumulate, but by placing the leads on a large beach towel etc, to wick it to the lead, you increase your alert time. The reason I put so many units in the boat I just placed them various points in the hull an topside under the sink hot water heater etc.
Now the downside of my alarms, those in units in the hull you need some one handy with good hearing lol .... Any tips you care to share?