We were attracted to the Willamalane Aquatic Center because we were interested in issues of thermal mass. An indoor pool is an ideal structure for this sort of analysis. Upon visiting the natatorium, there seemed to be a correlation between the variations in indoor air temperature and the different pool temperatures. The pool on the East side of the building has the highest temperature, and we noticed a higher ambient air temperature on the East side of the building.

Questions

• What is the source of the apparent difference in ambient air temperatures on the east and west sides of the pool area?

• Does energy from insolation contribute significantly to the building’s heat gains?

• Is the building internal-load dominated or envelope-load dominated?

• Is the internal air temperature driven by the pool water temperature, or by the HVAC heater?

Hypothesis

Although there are windows on the East wall, we believed that the large thermal mass of the pools would drive the indoor air temperature, rather than solar gains through the windows.

Our hypothesis is that:

The indoor air temperature of the Willamalane pool building will display a negligible diurnal temperature swing.

Merriam-Webster defines negligible as “so small or unimportant or of so little consequence as to warrant little or no attention.”