
Fallingwater
is in the midst of application of different paint systems for our exterior
paint testing program. In contrast to the rough
stonework, the reinforced concrete surfaces have a plasticity that is both soft
and warm. These concrete surfaces are
covered with a stucco-like concrete (commonly referred to as the plaster coat),
and then painted an ochre color reminiscent of the “sere” or dying rhododendron
leaf. Especially on the horizontal surfaces, the current paint is
delaminating and is generally not adhering well. On both horizontal and vertical surfaces, there is microbial
growth and efflorescence is becoming a problem.
The testing area is at the Guest
House Canopy facing south, which includes both parapets and horizontal
surfaces. We tried to choose a location
that will cause the least amount of impact on tours that still allow us a full
assessment. 2' x 2' areas are marked
off and both horizontal and vertical surfaces are being tested. Weather permitting, the final application of
paint systems will be applied the week of June 10, 2002. After all the systems are applied, the
temporary shelter will be removed and the application areas will be assessed in
September and March.

To remedy this, Wank Adams Slavin Associates (WASA),
a New York architecture firm, proposed different
waterproofing and roofing systems at different locations of the house. Work
is nearing completion on the Guest House Roof, Servant’s Quarters Roof, and
Herb Terrace Roof. For these areas,
WASA designed a Siplast system to incorporate three layers of defense against
water penetration. Gravel is currently
being loose laid over the finished membrane system and copper cap flashing is being installed.
The
Herb Terrace and Servants Quarters Terrace are currently receiving new
waterproofing systems. Once
Fallingwater maintenance catalogs and removes the stones, an asphalt-modified
urethane coating is applied over the concrete slab. After the material has set, two plies of a modified asphalt
membrane (with 3 plys of liquid membrane) are laid and a followed by a drainage
mat. The drainage mat acts as both a protection for the membranes and a way to
direct water to the drains.
The
paving stones are then reinstalled in a setting bed of 1 part Portland cement
to 13 parts sand. The joints in the paving stones are mortared with a mix
comprised of 1 part cement and 3 parts sand.
Copper flashing is located between the vertical walls and the paving
stones.