Built into the master-bath shower drain is a GFX Heat Exchanger, top right, which sucks heat out of the drain water and returns it to the cold-water line feeding the shower, thus lessening the demand for heated water. It recovers 60 percent of the heat that would be lost. Done properly, using one of these can be the equivalent of adding a solar water-heating system. This is not the only heat exchanger in the house. There is another, bottom right, that sucks the heat out of the exhaust from the backup generator and returns it to the solar storage tank.

And since we're talking about shower drains, it seems a good place to relate a story. Larry Weingarten asked me, Randy Schuyler, to help him raise a shower pan from the ground to the second floor deck. The thing weighs 400 pounds. He has an old Ford tractor and had tried to raise it using a boom, but the pan was so heavy that it lifted the back tractor tires off the ground.

He had an idea. He drilled a hole in one of the wall plates on the second floor and also drilled another hole through a 2x12, then ran a lag screw into both holes so that the 2x12 pivoted on the screw. Then he got a winch called a Come-Along and attached it to the 2x12.

My job was simple, I would ratchet up the shower pan with the Come-Along until it was level with the deck and then swing it around to rest there. His job was slightly more complicated. He was going to be a human counterweight, hanging onto the other end of the 2x12 -- and swinging out over empty space when the shower pan swung in.

I was nervous... I had visions of the balance shifting ever so slightly and launching my best friend like a catapult into an adjacent oak tree where he would abruptly perish -- leaving me to finish a life of guilt! Happily, most things that Larry figures turn out the way he figures them, as did this one: shower pan safely deposited, Larry still in one living piece, me no more guilty than before.