No announcement yet.

Balancing History and Efficiency

  • Filter
  • Time
  • Show
Clear All
new posts

  • Balancing History and Efficiency

    The modernization of the Wayne N. Aspinall Federal Building aimed to make it the U.S. General Services Administration’s first net zero energy facility on the National Register of Historic Places. The building is approaching this goal thanks to many strategies that help balance its historic significance with energy efficiency. Some examples:
    - A wireless lighting control system that reduces wiring demands;
    - Addition of storm windows with solar control film;
    - Removal of a drop ceiling, which previously blocked daylighting from some of the upper windows; and
    - A rooftop photovoltaic array that is set back far enough so that it is not visible when looking at the principal façade.
    What other strategies can help achieve the balance of historic preservation and energy efficiency? What are common obstacles for these types of projects and how can they be overcome?

  • #2
    Ventilation in Wonderland

    Charlotte Tubbs
    I am unable to justify Figure 1 on page 52 of the Summer 2014 article (Ventilation in Wonderland) against a 211.2 kBtu/ft2 annual (EUI) and a base loaded 4.6 MW gas turbine generator? With reference to Figure 1, what is the monthly gas usage of the turbine? What other than the turbine is using gas, especially during the summer months?
    Kirby Nelson


    • #3
      I remember doing several total renovations on courthouses (in the south, both on the registry).
      They were pretty much the same: The biggest restriction to work through was upgrading the exterior walls without changing their exterior. That meant that the insulation needing to be added HAD to go on the inside. This might substantially increase the wall thickness, causing problems with floor plan conflicts. To upgrade the insulation values, it hurt the budget to have to use expensive board insulation rather than going with the common batt. Batt would have puffed out the walls so thick that the window openings would have looked bad, and there were places where a thicker wall would have conflicted with floor plan features like stairs and interior doorways. Also, we were constrained on the energy efficiency we could shoot for, since we couldn't add solar shading to the exterior, a feature pretty much necessary for any really high performance walls in the south.
      Also, I had to account for increasing the HVAC total capacity, due to increased interior total loads. Even though we did upgrade the windows and those plus the exterior wall loads went down, the occupancy plus their ventilation caused the outside HVAC replacement unit to have to be larger (read heavier). It was on the roof, out of the sight line, so appearances weren't a concern, but the increased weight required closer coordination and some upgrades by the structural engineer.
      R. Edward Davis, PE, LEED AP
      Senior Mechanical (HVAC) Engineer
      Raleigh, NC


      Need Assistance?

      For assistance with ASHRAExCHANGESM, call 1-800-5-ASHRAE (1-800-527-4723) or (404) 636-8400 Worldwide or contact us online.