08.2 - 604 Brazos St - Driskill Hotel - Window Survey — original pdf

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Acton Partners, LLC PO Box 203663 Austin, Texas 78720-3663 TBPE Firm F-16437 www.ActonPC.com P: ACTON PARTNERS Sent via electronic mail to j January 14, 2025 John Bryant Vice President of Construction and Development Woodbine Development Corporation 1845 Woodall Rodgers, Ste. 1700 Dallas, Texas 75201 Re: Preliminary Letter Report – Window Condition Survey -- DRAFT -- Driskill Hotel Room Refresh APC No. 2024.0277 Dear Mr. Bryant: In accordance with our proposal dated December 10, 2024, Acton Partners, LLC Consulting (APC) has performed a field survey of the historic wood-framed windows at the Driskill Hotel and has prepared the following report summarizing our findings and recommendations. BACKGROUND The historic Driskill Hotel, located in downtown Austin, Texas, is a four-story Romanesque-style hotel structure located at the corner of East 6th Street and Brazos that was constructed in 1886. A thirteen-story tower was added to the north side of the historic building, along 7th Street, in 1930. Woodbine Development is planning ongoing renovations for the historic building, to include repairs to the exterior wood-framed windows. Accordingly, APC was engaged to review the condition of the wood frames, glazing, and perimeter seals. VISUAL OBSERVATIONS Window Frames and Glazing APC visited the site on January 2 and 3, 2025, to perform a visual review of the current conditions of the window systems from the interior of units, accessible low roofs, balconies, and ground level. Our observations of the conditions are described below. During our assessment, we directly accessed 115 of 189 guest rooms across the original 1886 building and the tower. At the historic building, the windows are typically fixed and single-hung, wood-framed units of varying sizes and geometries (Figure 1). The larger units have exposed exterior glazing putty between the single pane glazing and frames, some include muntins between glass units, and others include leaded stained glass (Figure 2, Figure 3, and Figure 4). The operable portions of the windows are fixed in place and are typically covered with a fixed storm/sound panel at the interior (Figure 5). Glazing putty throughout these units is in poor condition, appearing embrittled and with voids or missing exterior portions (Figure 6). At the tower, the windows are typically fixed, wood-framed units, with single pane glass held in place with exterior wood glazing stops attached to the fixed frames with finish nails (Figure 7, Figure 8, and Figure 9). Discontinuities are present throughout the tower in the back-bedded seals between the glass and interior portion of the wood frames, as viewed through the interior storm/sound panels (Figure 10). At both the original 1886 building and the tower, the wood frames and glazing exhibit signs of degradation and weathering, ranging from minor to severe. The more exposed units, at upper levels and south and east elevations, generally exhibit more advanced deterioration of frames and glazing stops, while the units that are more protected by adjacent buildings and balconies exhibit more moderate weathering. The glazing putty and frame-to-glass seals throughout are in poor condition. ACTON PARTNERS Driskill Hotel Preliminary Letter – Window Condition Survey January 14, 2025 Page | 2 As part of the field survey, we rated the condition of the wood sills, jambs, glazing stops, and sashes for each observed unit. The utilized rating scale is as follows: ▪ ▪ ▪ 1 – Severe Degradation: Wood elements exhibit degradation or damage beyond the point of repair, requiring replacement of the frame element (Figure 9, Figure 10, Figure 11, and Figure 12). o At many of the tower units, degradation of the glazing stops is most pronounced at the attachment points, leading to loss of compression of the glass at many openings. 2 – Moderate Damage: Wood elements exhibit surface-level damage or a discrete area of more severe damage, but the majority of the frame component is intact and the material can be repaired in place (Figure 13 and Figure 14). 3 – Superficial Damage: Wood elements are in fair to good condition but require priming and repainting (Figure 15 and Figure 16). Approximately 270 window units were directly reviewed via access to 115 guest rooms. Of the 270 units, approximately 66 percent were rated 1 – Severe Degradation, most notably at the sill glazing stops and sill frames and primarily at upper tower levels. The jamb and head frames and stops were in overall better condition due to their lack of continued exposure to moisture collecting against them, and head frames were typically in good condition due to protection from the masonry and lintels above. The below Table 1 provides a breakdown of the number of units exhibiting each level of damage: Table 1. Frame Condition by Unit and Location Building Area 1886 Historic Building Quantity Surveyed Rating* 1 2 3 Guest Rooms Windows Guest Rooms 48 94 67 38 (40%) 39 (41%) 17 (18%) Windows 176 141 (80%) 35 (20%) 0 (0%) 1930 Annex Total Guest Rooms Windows 115 270 179 (66%) 74 (27%) 17 (6%) *Unit/window assigned to the most damaged component Units under substantial cover of balconies above, units at the mezzanine-level terraces, and ground-level entrance units are in much better condition, likely due to a combination of protection and more frequent maintenance (Figure 17). However, several storefront units at the ground level that appear non-historic exhibit signs of moisture damage and weathering and are exposed to frequent water from the adjacent planters (Figure 18 and Figure 19). Only a few ground-level units appeared to retain the historic trim profiles (Figure 20). Additional Observations In addition to observing and rating the current condition of the wood elements of the window frames, we also reviewed the glazing seals, perimeter seals, and ancillary conditions surrounding the window units. Our observations of these items included the following: ▪ At many rooms, evidence of water leakage and resulting interior finish damage was present. We understand that moisture damaged interior finishes are frequently repaired at the interior, but that work on the exterior has generally not accompanied these repairs (Figure 21). Moisture-related damage observed during our survey included the following: ACTON PARTNERS Driskill Hotel Preliminary Letter – Window Condition Survey January 14, 2025 Page | 3 o Water staining on interior window frames, glass, and storm panels (Figure 22, Figure 23, and Figure 24). o Interior trim damage and paint delamination from moisture absorption (Figure 25 and Figure 26). o Water damage on trim and plaster elements inboard of the storm panels, including at heads of units below balconies above (Figure 27 and Figure 28). o Apparent biological growth on interior frame surfaces outboard of the storm panels (Figure 29 and Figure 30). This occurred most notably on west- and north-facing elevations. ▪ ▪ ▪ ▪ ▪ ▪ o Condensation on interior glass surfaces within the storm panels (Figure 31). In limited locations, broken glass is present, including at an event space and a few guest rooms (Figure 32). Cracked storm panels are present at the interior of a few window units (Figure 33). Stained glass within Room 254 appears to be deflected inward (Figure 34). Interior surface-applied film at larger glass units on the 1886 building is blistered and wrinkled in a few locations (Figure 35). Cracks are present in the stone sill units below windows, most notably at the tower, and separations are present along mortar joints between units (Figure 36 and Figure 37). Cracks and damage to exterior masonry elements were also present in a limited number of locations, including: o Corner balcony baluster deflection at multiple guest rooms (Figure 38). o Stair-step cracking at pilaster on Level 5 of east elevation (Figure 39). DISCUSSION AND RECOMMENDATIONS As noted above, damage was noted at almost all units, totaling approximately 93 percent of the surveyed windows. The most severe degradation is typically located at sills, glazing stops, and lower jambs of the tower units, but some degradation was also noted at sills on the 1886 portion of the building; significant levels of damage requiring patching or full frame component replacement were present at approximately 66 percent of frames. Moderate to minor damage, exhibited at most jamb and head frame components, typically requires only minor wood filler and paint repair. Degraded glazing seals and glazing putty were noted at all units and are likely responsible for the observed water staining, condensation, and apparent biological growth at interior surfaces. Moisture that enters through voided seals between the glass and frames can cause water leakage, and exterior relative humidity levels in the air can result in condensation and biological growth. Similarly, water that enters through degraded sill frame elements, failed perimeter seals, and discontinuities in the sill stone units and balcony waterproofing assemblies can result in interior finish and trim damage. The interior trim and framing components are generally in fair to good condition but exhibit evidence of delaminated paint and moisture-damaged wood and MDF. This damage correlates with the observed degradation levels at the exterior. Given the extent of the damage observed, we anticipate that full access to the facades will be necessary for this work and that nearly every window will require some repair. Our recommendations to restore the windows and address noted distress conditions are as follows. All work should be performed in accordance with historic repair procedures and The Secretary of the Interior’s Standards for the Treatment of Historic Properties1. Exterior Repairs ▪ In all locations, we recommend removing and resetting glazing within the fixed frames. This includes windows at the original 1886 hotel as well as the tower; recommended work sequence is as follows: o Remove exterior wood glazing stops and/or glazing putty. o Cut back glazing seals and remove existing glass, taking care to avoid damage to glass and frame components. o Clean glass and glazing pocket of debris and deleterious materials. o Repair or replace damaged portions of interior window framing. o Apply new glazing putty or silicone sealant into glazing pocket in a continuous manner. 1 The Secretary of the Interior's Standards for the Treatment of Historic Properties. National Park Service (NPS), 2017. https://www.nps.gov/orgs/1739/secretary-standards-treatment-historic-properties.htm ACTON PARTNERS Driskill Hotel Preliminary Letter – Window Condition Survey January 14, 2025 Page | 4 Set glass into glazing pocket in a level and plumb manner. o o Tool exterior glazing putty/setting sealant and install new exterior wood glazing stops set in glazing tape or silicone sealant. ▪ If only partial repairs of the glazing are pursued, we recommend resetting glass in locations of known leakage or where visible gaps and/or discontinuities in the glass-to-frame interfaces were noted. At a minimum, this should include the following work: o Reset glass at upper tower levels and discrete lower levels of identified water leakage and interior damage. o Cut out and replace exterior glazing putty at the 1886 historic windows, including cleaning of the glazing pocket outboard of the glass. ▪ Windows identified with minimal frame damage should be scraped of loose paint, primed, and repainted. This includes scraping loose paint, replacing pieces that are severely damaged, filling small areas of damage, removing and replacing broken glass lites, and cutting out and replacing degraded glazing putty, then priming and painting. ▪ Windows identified as having partial-depth or discrete areas of frame damage should be repaired by scraping loose paint, cleaning surfaces, and filling damaged wood frame elements prior to priming and repainting. ▪ ▪ Windows identified as the most damaged, with highly degraded frame components experiencing section loss, should be repaired by removing and replacing the damaged frame elements. Adjacent frame elements to remain should be sealed to the new wood framing in a watertight manner prior to priming and repainting. To reset the life cycle of the perimeter seals between the frames and brick we recommend cutting out and replacing sealant at every opening. If only discrete repairs to these seals are desired, we recommend removing and replacing sealant along all sill conditions and where perimeter frame elements are replaced. Though not specifically included in a window restoration scope, we also recommend removing and replacing or patching cracked sill units to limit the volume of water that can travel behind the exterior masonry wythe. ▪ ▪ We understand repairs are ongoing to address the baluster deflection and waterproofing at corner balconies. This work should include integration of under-tile balcony waterproofing with building walls to prevent water penetration into the heads of the units below. Interior Repairs ▪ ▪ ▪ Temporarily remove interior storm panels to access the interior frame ele ments where damage or degradation are present. Replace broken storm panels in discrete locations. Clean and scrape delaminated paint, prime, and repaint interior frame elements. Where MDF frame elements exhibit damage, we recommend removing and replacing them with wood frame components to avoid future moisture damage. Remove and replace damaged interior trim components with wood trim matching the historic profiles. Remove and patch delaminated interior plaster and repaint to blend with existing, adjacent walls. ▪ ▪ ▪ Where biological growth is present between the frames and interior storm panels, remove the storm panels and clean exposed surfaces per approved remediation procedures. o We recommend continuing to monitor these locations for further signs of condensation and damag e; further work to seal off the interior storm panel and prevent interior moisture ingress between the storm panel and historic windows may be required. ACTON PARTNERS CLOSING Driskill Hotel Preliminary Letter – Window Condition Survey January 14, 2025 Page | 5 This report is based on our visual observations of accessible conditions at the time of our visit, as noted above. Other conditions may exist or develop over time that were not found during our visit. APC reserves the right to modify our findings should additional information become available. This report was prepared on behalf of Woodbine Development Corporation and does not represent a design or specification for repairs. APC is available to provide further consulting, including preparation of repair documents, upon request. We hope the above information assists you with this matter. Please do not hesitate to contact us should you have any questions. Sincerely, Erika Bonfanti, PE Associate Principal Acton Partners, LLC Texas Registered Engineering Firm F-16437