Thermal/Hygrothermal Simulation

RDH can analyze and provide an evaluation into the long-term behavior of any building enclosure assembly or detail for thermal and hygrothermal performance (heat, air, and moisture control).

Utilizing state-of-the-art software (WUFI Pro 5.0, HEAT 3, THERM), thermal and hygrothermal simulations are used at various stages through the life cycle of a building for different purposes. Thermal modeling software is used to analyze one-, two-, and three-dimensional heat transfer under both steady-state and transient conditions.

The majority of RDH technical staff have formal training in building science, including several staff members who hold master’s degrees with specializations in building science. This training is imperative to understanding coupled heat and moisture transfer and in successfully utilizing and interpreting the results output from analysis software.

Because of our advanced building science understanding and depth of experience in the use of various building science software packages, we are able to provide training on those packages and on utilizing the results. Several RDH staff members regularly apply this knowledge in the instruction of students at universities and colleges on the west coast.

Hygrothermal Modeling

Hygrothermal modeling is the computer-assisted simulation of heat, air, and moisture flow through building enclosure assemblies (walls, roofs, floors, below-grade). It is the process of simulating the performance of assemblies so that the future durability and risk associated with different assembly designs, materials, and climate or exposure can be evaluated and assessed. For example, the risk for condensation within an assembly can be analyzed with different insulation or vapor retarder properties, or the influence of driving rain on cladding degradation can be predicted. The hygrothermal model results include temperature, humidity, and moisture content data at materials and at interfaces throughout the assembly. With this data, the user can assess the risk of condensation, moisture entrapment, fungal growth, and even material degradation.

Thermal Modeling

Thermal modeling is essential for establishing overall thermal performance values (R-values/U-values) and condensation potential. These tools are used to:

  • Evaluate the performance of proposed roof, wall, and glazed assembly designs.
  • Help design more thermally efficient and durable details.
  • Provide insight on forensic analysis.
  • Support energy code compliance documentation (i.e., ASHRAE 90.1) or energy credits for LEED projects.