Some appliances, such as water heaters, dish washers, and washing machines use water, and can leak and cause damage to a house. Is there any product or solution to catch and drain leaks outside the house?
Water heaters have pans. You place the pan under the water heater, then attach a hose to send the water someplace less damaging.
You can also get water sensors, which rest on the floor and sound an alarm if water is detected.
There's less stuff for dishwashers and washing machines, as they only contain water when in use, and there should be someone nearby when in use. Water heaters are commonly left alone for weeks on end, which gives more time for a small leak to turn into something damaging.
I've fulfilled customer requests for overflow trays in cases of integrated laundry equipment, for example. You'd essentially install or build a shower pan (with all the same drain plumbing). What type and profile is appropriate depends on the situation. I wish my dishwasher had one as a one-time overflow recently did significant damage to my kitchen floor.
For concealment a full-area grate could be installed at floor level or as an elevated platform.