World Heritage Preserved Blog

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In 2019, Fallingwater began fundraising for a major preservation initiative, the World Heritage Preserved Campaign, to repair its major building systems: stone walls, flat roofs, flagstone terraces, steel window and door frames, and concrete. 

Thanks to grant funding from the Commonwealth of Pennsylvania’s Redevelopment Assistance Capital Program, Governor Josh Shapiro, and several foundations, along with the generosity of many Fallingwater members, work is now underway to preserve or replace these vital systems. 

This blog was developed to provide you with regular updates on preservation progress and insights into various project aspects, including information on the talented people doing the work.

Watch this short video from Fallingwater Director Justin Gunther where he explains why we’re doing this important work over the next few years and how the various projects help ensure the long-term preservation of this landmark, one inscribed on the UNESCO World Heritage List. We encourage you to join us on this journey by reading the project updates section below to see preservation in action and, together, we can forge the future of Fallingwater.

Project Updates

May 24, 2024 Work Continues at the Guest House and East Terrace

April showers didn’t bring May flowers, but rather delayed preservation activities at the Guest House and Main House East Terrace and ushered in a reminder of the importance of our comprehensive World Heritage Preserved restoration effort.

As if on cue, the wettest April ever recorded in the region since 1871 was ironically perfect timing for us to test if the various applications of grout injection and masonry improvements worked to avert and prevent water from entering the Guest House and Main House. Although there was success, we learned there is still more work to do.

We were pleased to welcome John Matteo of Matteo Ferran Structural Engineers back on site in late April to further evaluate the Guest House east parapet wall to determine the extent of necessary demolition to repair it. Through various assessments, he helped determine that the first 18 inches of concrete was intact and in normal condition.

However, he noted that in some areas, the stucco had delaminated and water was observed trapped within the layers of stucco and concrete. The deteriorated stucco was removed at one of the locations, and the concrete found behind it was in good condition. Careful demolition of the east parapet wall occurred, though ultimately most of it was removed due to its poor condition. Members of Fallingwater’s maintenance team then worked alongside masons from Graciano to reconstruct the parapet.

Other Guest House masonry repairs included the dismantling of the stone parapet wall above the furnace room roof to reveal the existing slab construction and its waterproofing material transition between the furnace room and Guest House roof slabs. The disassembling confirmed additional waterproofing and moisture issues in these areas, all to be addressed in the coming month.

April 20, 2024 Addressing Main House Leaks Due to Heavy Rain Events

Mother Nature’s elements were on full display this April in the mountains of Southwestern Pennsylvania when heavy rains from several storm systems caused devastating flooding, high-velocity winds and property damage across the region. Fallingwater wasn’t immune, as water rose above the Plunge Pool wall and above the first two hatch stairs. But thanks to our quick-thinking and hardworking maintenance team, branches, litter and other debris that washed down Bear Run were removed before they could cause any serious damage to the house. 

Even so, moisture found its way inside the house, through the roofs and walls, and caused leaks in several locations, such as over the hatch in the living room caused by a cracked and deteriorated area of the concrete terrace above it. There are locations in the house, including Edgar Sr.’s study, Edgar jr.’s study and Liliane’s terrace, where leaks occur regularly during heavy rain events. Our contractors and maintenance teams conducted visual assessments throughout the house to identify additional water issues, which will add in upcoming repairs to masonry, roofing membranes and flashings in these areas.

On the dryer days, waterproofing repairs continued on the East Terrace. Allegheny Roofing and Sheet Metal contractors installed lead flashing at the masonry walls of the East Terrace. To prepare for applying silicone sealant, our maintenance team repointed the boundaries of the flagstones at the concrete walls and installed grout at the flagstone borders. A direct result of these applications, and other ongoing waterproofing and masonry work, will be to permanently address leaks in walls and ponding occurrences on the roofs and terraces.

March 18, 2024 Waterproofing on East Terrace Completed in time for 61st Tour Season Opening

As we prepare for Fallingwater’s 61st tour season, we are pleased with the progress that occurred over the winter months. Waterproofing the East Terrace was completed by Allegheny Roofing and Sheet Metal contractors. Once the contractors finished, our maintenance team carefully replaced the flagstone and filled its mortar joints to return the terrace’s topmost layer back to its original appearance. Because the mortar needs to cure, the terrace will remain closed to the public into April.

We also removed the scaffolding along the driveway and front entrance after dismantling the temporary heating system installed to allow the masons to work comfortably while they completed grout injection, installation of capstone flashing and stone repointing. Our entire maintenance team was needed to efficiently “unwrap” the house for visitors to enjoy the new preservation work on opening day.

February 26, 2024 Masonry and Roofing Work Continues at Fallingwater

This month’s preservation work involved erecting scaffolding and then wrapping it in plastic to create a warm environment for contractors to work. Three scaffolds along the north face of the main house allow for grout injection along the driveway and repointing of the north wall of the main entrance, dining room and kitchen area.

Using the knowledge gained from the Guest House, grout was injected systematically along the pottery terrace roof parapet, while the repointing crew worked near the kitchen door and Edgar Kaufmann Sr.’s terrace. Providing heated temporary enclosed spaces necessitated an additional generator to increase power to keep the masonry at a consistent temperature for efficient (and effective) repointing.

The roofing team finished work on the concrete roof of the bathroom in the Guest House applying pea gravel to finish the waterproofing system there, and continued preparing for a waterproofing membrane on the skylights above the library desk and beneath the flagstones of the East Terrace.

January 23, 2024 Waterproofing Membranes and Flashings Are Installed on the East Terrace and Guest House

As we begin a new year, contractors and the Fallingwater maintenance team erected temporary enclosures on the East Terrace to keep the work site warm and dry. The maintenance team carefully removed all the flagstones to expose the underlying waterproofing membranes. Then, the roofing team removed the existing membranes in preparation for installation of new materials.

As work progressed on the East Terrace, the roofing team simultaneously worked on the roof of the Guest House in another temporary enclosure. Here, the team applied a new waterproofing membrane to the concrete slab roof of the bathroom, an area Frank Lloyd Wright referred to as the “monitor.”

December 20, 2023 Enclosure Of and Work On the East Terrace

As we continue preservation, the next area of focus is the East Terrace. Some temporary exterior changes to Fallingwater have occurred in conjunction with our ongoing work. Before the roofers can install new waterproofing membranes and flashings to the terrace, our Fallingwater maintenance crew prepared the area.

First, our team erected a temporary enclosure to keep the work area warm and dry. Then, they removed the flagstone and underlying bedding of sand to expose the existing waterproofing membranes below.  Once the terrace is prepared, the roofers will remove the existing membranes and replace them with new ones to make the terrace watertight.

Although access to the East Terrace will be closed while this work is completed, visitors on tours through December can observe this preservation work in progress.


November 30, 2023 Prepping for Cold Weather

Due to cold weather during November, extra steps were necessary to keep Fallingwater’s preservation projects on track. One added step was creating an enclosure for the roofers. This kept conditions warm enough to apply a waterproofing membrane onto the raised roof of the Guest House bathroom, which Frank Lloyd Wright always referred to as “The Monitor” in all correspondences.

We also constructed an enclosure over the main stone masonry wall of the Guest House. In addition to this enclosure, the masonry team draped blankets over the stone to keep the work area warm. If the mortar gets too cold it won’t adhere to the stone as it dried. With the grout injection completed at the Guest House, a five-man team finished work in this area by repointing the walls.

October 30, 2023 Grout Injection at the Guest House Continues

October was another busy month for the Masonry Solutions International team. They worked to meticulously inject grout into the voids, left during the original construction, of Guest House walls. The method used prevents the development of air pockets. Injecting the walls with grout will improve overall wall stability and integrity, and decrease the ability for water to enter the house from the roof.

The team used water to wash away extra grout material in an effort to prevent staining of the exterior stone wall surfaces. This clean-up method also ensured a finished appearance to the walls.

September 23, 2023 Concrete Work Continues on Guest House Roof

In this short video, Scott Perkins, Fallingwater’s senior director of preservation and collections, provides an update on some of the preservation work that occurred during September on the Guest House roof. Learn about work to replace portions of the concrete roof and see some of the new products and materials being tested to prevent water from entering the Guest House from underneath the capstones.

You’ll also see one of the voids at the top of a Guest House wall, where grout will be injected to fill the space in an effort to prevent further water damage.

Learn more in this two-minute behind-the-scenes glimpse by clicking the video play button to the left.

August 21, 2023 Fallingwater Senior Director of Preservation and Collections Scott Perkins Gives a Brief Update

Thanks to the generosity of many private donors, foundations and Commonwealth of Pennsylvania funding, work is advancing on Fallingwater’s major building systems that need urgent attention.

In this short video, Fallingwater Senior Director of Preservation and Collections Scott Perkins gives a brief update on some recent work at the Guest House to replace the waterproofing membranes on the roofs and terraces, repoint and grout stonework to prevent water leaks and repair degraded concrete. This important work is being accomplished by preservation contractors and professionals. Stay tuned for more updates from Scott and others as work progresses!

To watch this two-minute video, click below.

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July 17, 2023 Meet Pamela Jerome, Lead Preservation Architect for Fallingwater’s World Heritage Preserved Projects

Involved with Fallingwater’s preservation since 1988, Pamela Jerome is the lead architect overseeing the preservation work associated with Fallingwater’s World Heritage Preserved Campaign. As the president of Architectural Preservation Studio, DPC, a New York City-based architecture and preservation firm, Pamela is recognized as an international expert in cultural heritage with a specialization in masonry conservation and waterproofing.

Pamela’s team produced the 2019 Fallingwater Preservation master plan incorporating new research, investigations, prototype repairs and the execution of an existing conditions assessment, all to update the previous 1999 master plan which Pamela helped create more than 20 years ago. The current three-year phased plan is underway and scheduled to be completed in late 2025.

Pamela says her past Fallingwater experience was rewarding and informative, and will be vital to the success of the current preservation work. “For Fallingwater, we have designed discreet interventions that improve the functioning of the exterior envelope. We also have the benefit of knowing what worked and what did not. I was the project manager for the first holistic restoration from 1999-2002, so I personally have a lot of institutional knowledge and insight about the technical issues that face Fallingwater.”

Pamela is assisted by APS Studio Manager Stephanie Gerard and APS Architectural Preservationist Vishal Joshi. Combined, these three architects bring more than 60 years of expertise to our project.

In addition to Fallingwater, Pamela and her studio have preserved some of the most important buildings of the 20th century, including Frank Lloyd Wright’s Solomon R. Guggenheim Museum, the historic Breakers and Château-sur-Mer mansions in Newport, Rhode Island, and Louis Sullivan’s Bayard-Condict building in New York City.

June 23, 2023 Guest House Repointing Continues

Throughout June, Graciano’s masonry team has continued with the next task of the preservation work. They repointed the walls of the Guest House with mortar. Visitors to Fallingwater during the month saw scaffolding assembled at the Guest House. It was erected to keep our masons safe and provide them with access to all levels of the stone walls.

The Graciano team also prepared the tops of the Guest House walls for through-wall flashing by removing the capstones. Once placed this metal flashing will create a waterproof barrier underneath the capstones. This will prevent the migration of water into the walls from their top surfaces. In the past, both rain and snow have entered the walls through this exposed stone surface.

May 22, 2023 Guest House Grout Injection Testing

Graciano, a Pittsburgh-based masonry firm, completed the mortar repointing in April which allowed for the next task in the Guest House project work: testing specified grout injection materials and methods for the Guest House stone walls.

Structural engineers from Atkinson-Noland Associates drilled small holes and inserted borescopes (thin, flexible, tube-like cameras) into the stone wall cavities to capture video and photography to monitor various conditions and moisture levels.

This visual monitoring and information helped Masonry Solutions International determine the preferred process and locations of where to strategically inject grout into the wall cavities. The work occurred during the evenings and on a Wednesday in May to lessen the impact to Fallingwater visitors.

April 27, 2023 Guest House Pier Repointing

Graciano, a Pittsburgh-based masonry firm, completed a small masonry repointing project on the northeast corner pier of the Guest House on April 25 and 26 to prepare the pier for a mock-up test of the grout injection process. This test addresses water infiltration concerns by inhibiting the movement of water within the voids of Fallingwater’s stone walls. The work also included matching existing mortar in both color and composition.

The test will provide insights into how to successfully use the process in upcoming preservation projects. Pamela Jerome, our preservation architect, and John Matteo, our structural engineer, specified the grout injection process to address the effects of water infiltration.

“Fallingwater’s original materials are conserved and preserved whenever possible,” says Fallingwater Senior Director of Preservation and Collections Scott Perkins. “Yet we also need to consider newer techniques and methods to demonstrate to our visitors and members the excellent stewardship methods we are undertaking.”

March 22, 2023 Steel Frame Conservation

H. P. Steel Window Restoration completed conservation work on the original Hope’s windows in the Guest House. The team began repairing areas of corroded steel on the clerestory window frames from March 16-23. They primed and painted the frames with coating products manufactured by Tnemec (“cement” spelled backward).

The glass panes of two clerestory windows on the north elevation of the Guest House are embedded into mortar-filled channels in the stonework and needed to be replaced because of separation or cracking along the surface.

Finally, Advanced Caulking Services sealed the replacement glass using a thin bead of silicone to minimize the potential for future cracking. The color-matched silicone honors the original intent of Frank Lloyd Wright while allowing the glass to float within channels to better react to weather changes.

February 24, 2023 Wood Furniture Removal and Stone Wall Mortar Repair

One of the first activities to prepare for the preservation work on Fallingwater’s major building systems was the temporary removal of built-in casework, desks and wall shelving in the Guest House bedroom, Edgar jr.’s Study and Edgar Sr.’s Dressing Room and Study. This work was completed throughout February by our wood conservators to expose the stone walls for mortar work.

Fallingwater’s maintenance team repaired hairline cracks in the mortar joints of the stone walls of the main chimney and established various test sites within the Guest House. Using a process called repointing, the team removed portions of the deteriorated mortar using hand chiseling tools and added new mortar to the joints to repair the cracks. Filling these cracks prepares the walls for a future grout injection.

This extensive repointing process also helps seal the walls from within to help prevent further water infiltration. After the repointing was completed, the built-in furnishings were set back into place by the conservation team. To prepare for the season’s March 11 opening date, Fallingwater’s housekeeping team cleaned and reset each room with its furniture, artwork, books and decorative objects.