The University of Wisconsin -Eau Claire (UWEC) Karlgaard Towers (Towers Hall), located in Eau Claire, Wisconsin, is a dormitory on the upper campus at UWEC. Karlgaard Towers consists of Towers North and Towers South. The dormitory was renovated in the fall of 2017, and the renovated Towers South opened to students for the fall semester of 2018. Towers North underwent renovation in 2018-2019.
After students moved into Towers South in the fall of 2018, occupants and school personnel noted winter-season building performance issues, including surface condensation, water staining, and suspected mold growth on interior wall surfaces. Towers North also experienced moisture-related problems during renovation, like those reported in Towers South.
The South and North Towers Hall is ten stories with 630 residence rooms built in 1966.
Services Provided
Jim was able to zero in on the problem quickly and was timely in his effort. He explained the issues well and communicated the solution options and associated cost in a manner useful to us. His cost estimates proved to be thorough and accurate providing us the confidence we need in our decisions."
Andrew Nord – Facilities Planning & Construction – Construction Project Manager
Gallery
Challenges
We would definitely work with Jim and CR-BPS again. They were timely, thorough and created good value for the dollar we spent."
Andrew Nord – Facilities Planning & Construction – Construction Project Manager
Approach
University Facilities staff used data loggers to record the affected dormitory rooms’ temperature and relative humidity conditions. Furthermore, CR-BPS conducted a diagnostic analysis to identify the root cause of moisture accumulation on the interior surface of the exterior walls. This methodology encompassed the examination of background information, interviews with staff members, and the analysis of data logs documenting relative humidity, air temperature, and air dew temperature within the rooms over the winter. Additionally, airtightness testing was conducted in conjunction with infrared scanning.”
The data logger data confirmed the presence of excessive relative humidity within the rooms at specific times on multiple days throughout the winter season. The diagnostic analysis concluded that the uncontrollable excessive relative humidity conditions in the dormitory rooms stemmed from the Basis of Design’s dependence on operable windows for ventilation air. CR-BPS additionally identified air leakage between rooms and floors, resulting in condensation in the interstitial areas of the exterior wall assembly.”
Two ways to control interior wall surface or interstitial wall assembly condensation:
- Warm the surface temperature of the building assemblies.
- Control the relative humidity of the air infiltration at the surface of the building assemblies.
Finding a practical and budget-friendly recommendation was a key step in the process.
The original as-designed and as-constructed exterior wall assemblies of Towers Hall made it impossible to apply interior insulation to the exterior walls to control the surface temperature of the building assemblies; controlling the winter relative humidity was the only practical solution.
Jim did a great job sharing and explaining information with our A/E consultant who we would ultimately ask to implement the solutions. CR-BPS communicated the findings and solutions well with everyone. Jim and the A/E worked well together."
Andrew Nord – Facilities Planning & Construction – Construction Project Manager
Results
CR-BPS’s evaluation and building diagnostics determined that the primary cause of winter season moisture accumulation and potential mold growth in rooms was high relative humidity levels, poorly insulated building enclosures, thermal bridging, lack of dormitory room mechanical ventilation, and noncontrolled air leakage.
CR-BPS recommended that a more practical approach than applying a better thermal control and airtightness control layer was to devise ways of controlling the relative humidity of the rooms. This required the compartmentalization of each room and the installation of individual unit ERV ventilation across exterior walls-not across interior pressure boundaries or installing a whole-building ventilation system.
UW staff used CR-BPS’ report and further consultation with maintenance and University engineering staff. They determined that a whole-building ventilation system, albeit the more expensive option, would be the best long-term solution.
In 2020, Greenfire Management Services LLC was awarded the contract to construct the “Condensation Repairs for Tower Hall,” including the North and South Towers.
Towers Hall’s Condensation Repair renovation included installing four new 7400 CFM Energy Recovery Units and all the supporting distribution systems to each room in both Towers. Ductwork runs from the rooftops down vertically to all the floors, then branch lines horizontally to each dorm room. The work was constructed in multiple phases during the summer months to minimize disruption.
The solutions recommended by CR-BPS are working great and we would for sure consider working with them again. We would consider using CR-BPS on our project teams such as “owner’s representative” during design, construction and commissioning. We are always looking for other architects and building science consultants."
Andrew Nord – Facilities Planning & Construction – Construction Project Manager