10:30 am - 11:50 am | Room: Owens Corning Room | Session Chair: Jelena Madzarevic

Moisture Management In Buildings

Controlling Moisture-Induced Failures With Engineered Hardwood Flooring

Within a year of opening, the engineered hardwood flooring installed throughout the second level of a retail store, located in a major shopping centre in Toronto, started to buckle leading to widespread trip hazards. The engineered hardwood flooring was intended to be fully adhered in place. 

An evaluation was initiated to diagnose the factors contributing to the observed buckling and to determine appropriate repair and management strategies. The evaluation included targeted removals to review flooring substrates and adhesive patterns, in-store ambient relative humidity and temperature monitoring across various zones, flooring adhesive bond testing (at locations adjacent to areas with localized buckling and in control areas that had not buckled), and laboratory testing of engineered hardwood samples. 

Information about the expansion/shrinkage response of engineered hardwood flooring to changes in ambient relative humidity is not readily available within the industry or from manufacturers. The expansion/shrinkage response of engineered hardwood flooring is difficult to predict since it is typically manufactured with both hard and soft wood species. Engineered hardwood flooring samples were sent to a laboratory where they were placed in chambers with various ambient relative humidity conditions and the corresponding changes in plank size were measured and plotted. A corresponding function was developed that allowed the magnitude of expansion and upward buckling to be predicted with a reasonable degree of accuracy given a number of successive debonded planks and a given change in ambient relative humidity.

Several factors were deemed to contribute to the observed buckling. Poor installation techniques initially led to flooring debonding, and then buckling subsequently resulted from moisture-induced expansion. 
The principal authors of this paper have experience diagnosing and repairing flooring issues resulting from poor installation techniques and moisture-induced deterioration. This paper provides a case study to encourage designers and installers to consider floor flatness, expected initial and in-service ambient relative humidity, adequate periods of engineered hardwood acclimatization, and quality control testing to check adequate adhesive coverage and bond, to promote improved flooring performance and durability. This paper also provides expected engineered hardwood shrinkage/expansion response with changes in ambient relative humidity.

Adam Thompson, Synergy Partners

Adam is a Project Manager with Synergy Partners Consulting Limited, responsible for the successful delivery of building restoration projects. Adam specializes in roofing technologies and recently received his RRO designation. Adam chairs Synergy’s Technology and Innovation committee. Adam has been with Synergy since 2017, and during that time has expanded his knowledge base as he has worked alongside some of the industry leaders in the building science and restoration engineering fields.