Green Building Studio (Group Project) _ Tutor. Khee Poh Lam 

One Montgomery Plaza _ Revit modeling, GBS simulation  

This Study represents energy simulation study of an eleven-story office building located in Norristown, Pennsylvania. Autodesk Revit and Green Building Studio are used for modeling and simulation for the study. Physical components were modeled using Revit and thermal zones were then assigned based on usage, scale, orientation and circulation. The Revit file format was then converted into gbXML for simulation using Green Building Studio to obtain building performance results. The basic approach of this study is divided into two different paths; comparison of different situations (Norristown and Miami) and parametric study of energy suggestions. The purpose of this study is not only to develop high performance building but also to consolidate logical assumptions for designers to determine the optimal solution in the preliminary design phase.

Location _ Norristown, Pennsylvania

Norristown is a municipality located in Montgomery County, Pennsylvania approximately 6 miles northwest of the city limits of Philadelphia on the Schuylkill River with a population of 34,324 based on the 2010 U.S. Census. Norristown sits on a rich agricultural region, and the entire Municipality of Norristown is within the 19401 zip code.

Building Description 

The building for the simulation is an eleven story general commercial building constructed in 1973. The size of the building is approximately 215,000 square feet. The basic construction materials used were brick and glass with masonry building exterior construction. The core of the building located in the center of the auditorium contains four elevators, two restrooms, and two electric rooms. The main entrance of the building faces the Southeast and the general office spaces were generated on each building facades. 

Thermal Zoning

One-Montgomery Plaza consists of three main parts: perimeter, corridor and core part. In the perimeter part, two determinations (orientation, window) were applied. Orientation and window are key factors that determine the amount of solar heat gain. The second part, corridor, contains user density as a zoning determination. Some corridor parts in this building contains regularly occupied areas such as the secretary’s office, the pantry, and the lounge area. Lastly, the core part is divided based on the function of each room such as elevator, electrical, mechanical, and restroom.

Orientation Study

As expected, the south orientation (the baseline case) had the lowest EUI. Furthermore, a method to find an orientation for the lowest EUI was proposed. The underlying assumption of the method is that in the graph which displays the corresponding EUI in respect to the orientation, the EUI curve would be continuous. As shown in the table above, all of the local minimum EUI values of heating, cooling, and lighting occurred between the roated angle -10 degrees and 20 degress. Since GBS only allows making minimum 15 degree rotation, we came to a conclusion of applying the baseline case (south orientation) was reasonable. 

Envelope

Even though GBS suggests a number of options for roof/wall construction, the designer should run feasible options based on climate conditions for maximum efficiency. Otherwise, the baseline numbers produced by GBS trigger designers to be puzzled in the preliminary design phase. Fortunately, several organizations including Ashrae suggested recommended specification for roof/wall composition based on the climate zone.

Based on GBS selecting options, designers can try four roof and wall options for building energy simulation in preliminary design phase.

Window standard selection 

To reduce GBS window options, firstly we look at two different standards according to different zones.  The result of eliminating window list is shown in the chart below. The U-value and the level of SHGC of zone 4 is under 0.4 thus each red line was eliminated. Using the same logic, the value of each factor of zone 1 can be under 1.2 of U-value and under 0.25 of SHGC level. ASHRAE 90.1 was used as the first consideration for the basis of our decision as it has the most dominant impact in this option.