About the House:
The Rosenberg House was built in 1859 in Galveston, Texas by philanthropist and business leader, Henry Rosenberg. The graceful Italianate style combined innovative design and understated elegance for the time. After the death of Henry and his wife, the house fell into neglect before being purchased by the Sealy & Smith Foundation and donated to the University of Texas Medical Branch (UTMB) in 1989. Following an extensive restoration, the home has received much needed renovations to bring back its original charm and beauty.
The Problem:
The UTMB Galveston staff observed increasing signs of moisture in various areas of the home and mildew on pocket doors. Our sister company, W.H. Coltzer (WHCI) performed a forensic investigation to determine the moisture and mildew’s cause and suggest options for remediation.
WHCI Observations:
WHCI conducted a comprehensive investigation of the exterior and interior of the home. Here is what they found.
Exterior Observations:
- When a newer stucco veneer was applied over lath, which divides the walls into two systems a vapor retarder was not used.
- Isolated areas of cracked paint on the exterior indicate areas of moisture within the wall assembly.
- The sealant joint sizing at the window trim was too small and showed signs of failure.
- Though the exhaust vent was positioned correctly, the fan appeared to be forcing outside air into the home.
- During renovations, subflooring was put in place with a ploy vapor retarder as required by the floor manufacturer but framing for the interior walls made gaps in the vapor retarder.
Interior Observations:
- WHCI performed moisture readings and found extreme levels of moisture in the interior corridor. Levels decreased as readings were taken higher on the wall, indicating the moisture originated from below the flooring.
- The interior finish shows damage at the base of the walls.
WHCI Testing:
WHCI performed air infiltration testing with the blower door method throughout the entire home to determine the amount and cause of air leakage. Blower door testing uses fans to gauge the amount of air pulled out of a structure to evaluate the level of airtightness.
The test revealed a large number of leaks within the building envelope. If the air leaks were combined into one visual opening, it would be 1 inch tall by 42.52 feet long or 3.545 square feet. To determine where the air was entering the home, WHCI combined heatless smoke with the blower door test to pinpoint air leak locations in the home. Here are the results:
- Negative smoke test at the ground: The smoke machine outside the crawlspace vent drew down a negative vacuum on the interior. Smoke was immediately pulled into the crawlspace by the negative pressure and began to infiltrate at the stairwell base, lower exterior walls, and up through plumbing penetrations beneath the kitchen sink.
- Negative smoke test in the attic: The smoke machine in the attic drew down a negative pressure on the interior. The smoke eventually began to exit the house through an abandoned air return and at the tops of pocket doors on the second level.
- Positive smoke test: WHCI filled the interior with smoke and positively pressurized it while observing from the outside. Smoke exited the crawlspace vents, attic, and mechanical room.
WHCI Conclusion:
WHCI found that overall, the exterior envelope was in relatively good condition considering the age of the structure. The crawlspace proved to be the weakest link in the building envelope and the biggest culprit for creating moisture issues within the house. The attic space and mechanical room also contribute to air and moisture in the home.
The highly trained team of professionals at WHCI provided UTMB with an exhaustive report detailing their complete observations, tests, and recommendations.
