The first atrium has a floor covering which can't be soaked with water either.
The second Atrium has a solid tiled floor so water on that wouldn't be an issue. This atrium is kept from misting up with fin radiators in underfloor channels covered with stainless steel mesh. All these mesh protectors would need to be removed and the year's rubbish vacuumed out of the channels. It consists of broken school pens, chewing gum, chocolate paper wrappers as well as the usual floor dirt that accidentally ends up in the channel rather than being swept up by the cleaners.
Once done, those channels would make a rather good collection point for run off water. I had very seriously considered wfp in the sections where there are no doors and electrical wiring, but we got water into one of the door alarm sensors cleaning the windows outside wfp one year. That cost the school more in a call out and repair to the sensor than we charged for the clean inside and out.
The other issue we have is those very large pillars and beams that make up the roof support system. We would have to do the top 2 rows of windows by hand anyway. The very top windows in black have electrically controlled openers for air and smoke ventilation. The lower beams would get it the way of cleaning wfp unless we could get a long enough goose neck.
It takes us 11 hours to do those internal windows. We have to wait whilst the tower is raised/lowered between the two floor levels. The qualified caretakers may not be available when we want the job done.
However, the up side is that whilst son in up on the tower with his fall arrest system on, I can clean the lower windows 4 rows of glass from the floor with a swivel squeegee on the end of an Unger Teleplus ali pole.
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