by davejohnson on Mon Jan 27, 2014 1:39 am
It's been a long time (1995) since I was at Grace Church, and I don't reliably remember the physical configurations there.
In particular, I don't remember if the playing cabin is an island unto itself in the tower or if it shares one or more of its walls with the tower walls themselves. Your description of major moisture inside the playing cabin--including, amazingly, on the clavier itself--tells me that you've got significant air circulation, insulation, and construction problems that should be addressed immediately by a professional. If this is more a winter season problem, try to get advice now.
The mortar deterioration that you mention, if proximate to the playing cabin, would almost certainly contribute to the moisture problem, but not as you describe it, i.e., you indicate that sudden atmospheric shifts can quickly produce moisture in the cabin. Tower deterioration is permanent and steady; your problem is situational. The tower itself could well have moisture issues: House of Hope Presbyterian in St. Paul, where I play, was found to have moisture issues about five years ago when time-lapse photography revealed that the tower in which our carillon is housed was shifting. These weren't radical shifts, but there clearly was instability. Subsequent close inspection revealed that the brick inner construction (there is no iron or steel in the tower, which is faced with Bedford limestone), was completely deteriorated throughout the upper portion of the tower owing to moisture. The church immediately opted for a complete professional rebuild. The brick turned out to have become pure powder. The top ca 25-30 feet of the tower was subsequently completely rebuilt. This winter, for the first time in at least fifteen years, there has been no observable condensation and icing in that portion of the tower stairwell that is exposed to the exterior tower walls themselves. The rebuild clearly achieved its purpose.
As for our playing cabin, it was built, along with a practice room two levels down in the same tower, in 1992, by Verdin under the direction of Rick Watson, who conceived and designed a complete restoration and renovation. We have two fine rooms with proper air circulation and insulation. I've never found moisture in either room. The playing cabin has independent walls, facing the outside with windows, on all four sides. These windows open, and are opened to the player's desire. The bells are immediately alongside (the three largest) and above (46) the playing cabin. The practice room has direct contact with an exterior wall on one side, and with other interior space in the tower on the other three sides. In other words, on only one of eight total sides do our rooms have physical contact with the tower walls.
In summary, our tower has two well-insulated, well-ventilated rooms, professionally designed and constructed. The only extant issue at the moment is that heat in the playing cabin has bordered, during this exciting cold winter, on inadequate. We solved the same problem in the practice room by replacing the baseboard heater with a bigger one, and we'll do the same in the playing cabin before next winter.
I think you need immediate professional advice, and hope that you'll seek it.
Dave Johnson