I watched men and women construct such a building in Frankfurt, Germany during March of 1997. They were getting ready to turn the place over to the owners when I visited there. I was with some friends and we were getting a tour of the building, courtesy of Mr. Grohal and Mr. Thaler, who are proud engineers. They took the time to show me their work, and for that, I will always remember them. As I said, some places (and some people!) just live on in the mind.

They called it the Kastor and Pollux building. It is 426 feet tall, a very good size for this bustling commercial city. Three independent hydronic-heating systems served this building. They built it that way to avoid high static pressures. These guys wouldn't dream of heating a building directly with steam, as we've done in so many of our big American cities. In Germany, they consider steam heating to be a technology of the 19th Century.

But they did have steam in the basement. In fact, Mr. Grohal and Mr. Thaler were gushing over how unusual it was to use steam, albeit it indirectly, to heat a big building. They walked up to this impressive plate-and-frame heat exchanger and started to explain to us how they were taking 60-psig steam from under the city streets and moving massive amounts of BTUs into the water that coursed up through the building. I let my eyes go wide and never mentioned that, in New York City, this was like white bread in a supermarket. No big deal. But they were so eager to explain it all to me that I kept my mouth shut. I found their enthusiasm delightful. I have such a deep appreciation for passionate engineers. And I don't care where they live.

When we finished marveling over the steam in the basement, we all went upstairs to wander around. About 80% of this place has direct hydronic radiators. Hydronic coils in the ventilation system pick up the other 20% of the load. The best part for me, though, was the atrium lobby where they were using a radiant floor heating system. That's something I don't see in New York City office buildings.

In Germany, many of the engineers have also been specifying hydronic radiant heat in the lower part of the walls, below any expanses of glass. This is to counteract the downward convective flow of the colder air that's falling from the windows. They don't bury the tubing too high up a wall, though. Someone just might hammer a nail through a tube. They're also aware that a radiantly heated wall will set up convective air currents in a room, and that's something they try to avoid, especially in rooms with high ceilings.

In this building, they placed decorative hydronic convectors at several levels across the lobby's glass wall. Here, too, their goal was to keep cold air from falling, and it seemed to work beautifully. The space was very comfortable. Near the lobby's revolving doors, they placed high-output convectors to counteract the cold air that came in with the people. If you used your imagination, you could "see" the air currents in this space trying to rise, trying to fall, and then finding a point of equilibrium. A lot of thought went into those invisible air currents. And this, by the way, is the sort of thing that annoys the spouses of Wet Heads. We can stand in one place for the longest time, staring at invisible air currents.

"What are you looking at, honey?"