Overview and Presentation - Brianny Martinez

Throughout the design project, I worked towards achieving my project goals which were to design a net zero building, use sustainable/durable materials, and maximize green space. The design features that I initially planned for included high R-value construction, high albedo and SRI façade, maximize daylighting while using thermal mass to reduce excess heat, daylighting sensors, photovoltaic panels, sustainable cement (through the use of supplementary cementitious materials such as fly ash and limestone calcined clay), and maximizing green space through green roofs and green walls.

During the design process, I was able to model several of these features. I modeled high R-value exterior walls, maximized daylighting through a high window to wall ratio and through skylights, modeled shades on the windows/curtain walls and considered building orientation, included trombe walls/columns to absorb excess heat, reserved a high % of roof area for PV panels, modeled a green roof, and reserved a large percentage of the site to an outdoor green space.

From a pre-design/planning phase standpoint, I am proud of how I planned the flow of the convention, especially how the layout would impact a person’s well being. I intentionally split the main attractions, the exhibition spaces, between the two L-shaped buildings in order to encourage guests to walk across the outdoor green space to reach the other two exhibits. This technique not only promotes physical health, but it also encourages them to interact and be with nature.

In terms of design, I am proud of the shades which regulated the amount of heat entering the building (minimizing the building’s cooling load). My high glazing percentage also maximized daylighting while providing views to nature. Despite concrete being my primary structural material, I was able to achieve a high R-value in the exterior walls by modifying the wall system and adding a high R-value interior insulation. This allowed for my design to be both efficient at storing excessive heat through concrete’s high thermal mass, and at minimizing the loss of cool air to the outdoors. The green roof I modeled enhanced the building’s insulating properties while decreasing the likelihood of storm water runoff. With a high percentage of roof area reserved for PV panels, I was able to accurately set a PV percentage in Insight; this drastically decreased the overall energy consumption of the building.

My structural system promoted an open floor plan which allows daylighting to reach further into the building without being obstructed. Regarding my HVAC design, I set the system to only provide cooling so there will be no heating loads on the building. I made this decision because Colima has high temperatures year round, when the temperature drops at night during colder months, the high percentage of concrete in the building will release heat to provide thermal comfort.

The biggest challenges came during the HVAC and plumbing system design. When I first designed the HVAC system, my calculated required CFM for each L-shaped building was very high. Therefore, I selected a single rooftop unit that was able to meet the high demand for each building. As I modeled the system, I only viewed the floor plan without checking the 3D and section views. Once the system was complete, I realized that the ducts were automatically being sized at a very large section size in order to accommodate the large required airflow. Once it was complete I found it difficult to resize the system while avoiding the concrete columns and beams.

After gaining advice on how to resize the ducts in mass quantities, I was able to partially mend the system so that it does not protrude through the ceiling but I did not have enough time to ensure the new system layout did not interfere with the structural beams and columns. In hindsight, I would place multiple handlers on the rooftop rather than just one. This would have solved the large duct sizing issues and allowed me to properly plan around the structural system.

Finally, the plumbing system was modeled properly but I would have liked to add restrooms on the second floor of the L-shaped buildings. When I was in the conceptual design/planning stage of the project, I thought it would be adequate to only have restrooms on the first floors. I now realize that it would be more convenient for people on the second floor to have quick access to restrooms as well. In hindsight, I would have allocated restroom spaces directly above the Level 1 restrooms so that I could conveniently copy the restrooms/plumbing system to the upper level.

The pre-design phase of a project is often overlooked; however, it is the most important. The emphasis we placed on conceptual design in this course allowed me to achieve all of my big successes and kept me focused on what I wanted to achieve throughout the process. If I had more time to contemplate the design, or had I done it more efficiently, I could have easily placed a plumbing system for restrooms on the second floor.

The analysis tools we learned to use throughout the course are crucial to making informed sustainability decisions. Without them, we might overuse materials, such as placing shades or tinting windows where it isn’t necessary, or not apply enough of a certain sustainable design technique. For example, I added low-e dark panes to my windows but when I ran the daylighting analysis tool, it showed that I was not letting enough light into the building. Essentially, the tool allowed me to make the informed decision to not place the tinting on the windows even though it seemed like any technique viewed as sustainable would be beneficial.

Finally, I would suggest thinking about the higher level systems (HVAC, structural, plumbing, lighting) early on, within the pre-design phase period. If I had considered the HVAC during this period, I would have avoided the duct sizing mistake by considering ahead of time that the large square footage would require a large unit. A general idea of what you want your systems to be and how they should perform based on your building geometry will save time and reduce future mistakes.