I put a layer of Masonite under the fridge, so that if I needed to roll
it out, I could just put a similar thickness piece on the floor to protect
the floor. However, I hadn't realized that my fridge didn't have anything
like a toe kick, so I could see the edge of the masonite, and it was ugly,
so I took it out.

My counters were borderline too high for my slide-in range, so I put
1/4" plywood under it, stained the edge to match the hardwood, and
cut it off pretty far back under the range. For the front feet, I cut two
2" circles out of 1/4" oak, sanded/stained/finished to match the floor.
If my counters had been 1/8" lower, I would not have done any of that.

We put our side by side refrigerator on our new evgineered hardwood floor directly. It is hickory and very hard. I think softer woods could be a problem because in our previous home there was Designer Solarian vinyl flooring in the kitchen and the wheels on the refrigerator made tracks in the surface when we had to move it. Small wheels and heavy = trouble. Like the idea of Masonite as a protector.

My SZ 632 side by side is rolled into place onto quarter-inch thick hardwood plywood strips about five inches wide and long enough to reach the back wall. Stainless steel sheet metal around 1/16th thick is cut to fit on top of these and spread the weight from the unit's four supports over a larger area. The floor is cherry and the unit is heavy with small supports, so weight spreading is essential.

Moving the refrigerator involves putting a full 4 x 4 ft sheet of this hardwood plywood in front of the SZ and pulling the unit from the strips onto the larger piece of plywood. By alternating two such pieces one can move the unit some distance if necessary. The hardwood plywood is the type made without voids for underlayment purposes. I suspect masonite would work just as well (as long as it is dry).

The strips reduce the amount of space that could be wetted by a spill. One doesn't want the entire underneath of a piece of masonite or hardwood plywood to stay wet for long.

With both a hardwood floor and a unit above it that can get it wet, a moisture alarm should be placed underneath. More complex arrangements with water shut off valves can be adopted for minimizing risk from icemaker connections.

A hardwood floor is beautiful to look at and comfortable to stand on, but for resisting kitchen spills and dropped utensils is about the least practical choice available. (An ipe or similar tropical hardwood floor might be an exception, being relatively impervious to occasional wetting and too hard to dent.)

kas

We have the "laminate flooring" and when we move the refrigerator out, we roll it over a cloth/towel and it doesn't mark the floors. If you can, use the "furniture mover things" under your appliances to move them....have to lift them up a bit (if possible) to slide the "movers" under.

My house has had a fridge and stove on top of solid oak hardwood flooring for 13 years. Both have been moved; the fridge numerous times. There is no floor damage at all.

I wouldn't try that with some of the giant fridges they sell now or on top of softer floors like pine, though.