A result of all these thoughts is till now one project. We gave it a code name of STACEY. It was basically for my graduation project, which was for 2 semesters; the 1st semester being for the theory bits, and the 2nd semester being for the practical bits. STACEY was submitted for 2 competitions so far; SRD 2010, and Holcim Regional Awards 2011. It did not win anything with the SRD (sadly), and we’re still waiting for the Holcim results which should be out in June/July. Through these posts, I am going to track down the process of engineering Stacey, from the very beginning. Let’s get started.
The unique thing about Stacey is that all its components have been designed in-parallel. That is, for example, while we were doing some simulations to calculate the amount of heat that gets into the building through the exterior walls and windows, we were also considering the amount of light that comes through these windows. The ultimate result would be walls and windows that have a low u-value, as well as windows that have a high VLT value (relative light transmittance) to allow for maximized daylighting. This way of engineering has been followed for all the components of the buildings, to ensure that no component compromises the performance of another, and instead, adds to it.
To take the initiative, I am going to start talking about the site. One of the 1st ideas I had was to have a “virtual site”, by which that building can be put nearly anywhere, and it could. But, because we wanted from the beginning to use LEED for Core & Shell as a criteria to follow for most of the decisions, we had to choose a site. LEED does not allow for the building to move at any stage of its lifetime, and the location should be decided.
Many factors did affect the decision of choosing the site (we’re not talking about making wanky statements with our building here; like making it more iconic from a certain street or locating it next to a mountain so that we can later say that its a natural extension to that mountain, which it wouldn’t). The site had to be close to at least 10 basic services (a laundry, a bank, a gym, a public park, etc.) The site also had to be preferably on a a previously developed land, and close to public transportation, as well as its contribution to decrease the heat island effect. Which, if you thought about it, would make up for a good site, that would benefit the people who are going to live in that building, as well as piece of land that hosts the building.
The site of the building is located in Al Karama district in Dubai, UAE. It has been chosen due to its proximity to local amenities, public transportation, not being a greenfield, and its ability to enhance the natural habitat.
The design of the site had taken many factors into consideration. Decreasing the heat island effect was a critical thing that had to be eliminated. The heat island effect is when a certain area of land has a higher temperature than it’s surroundings. That can be caused by have large areas of asphalt, or covering the roof with conventional low SRI value materials. The amount of asphalt on the site has been minimized to optimize open space and thus decreasing the heat island effect. That has been done through using a 2-level robotic parking system inside the building that uses at least 50% less space and 26% less energy than a conventional on-site parking. At that stage we didnt decide about the PV cells on the roof yet, but we did make sure that the roof was to be covered with vegetation (not so it looks green, but to decrease the heat island effect and the solar gain) or a high SRI material, which the PV structure later on contributed to.
Open space on the site not only contributes to the minimizing the heat island effect, but it also decreases the amount of storm water run-off, by absorbing all the rainwater into the ground. The plants used on the site are the traditional Ghaaf Trees (Prosopis cineraria) which require hardly any water to grow and their roots can find water 30m below sand dunes, which would contribute to decreasing the amount of water used for landscaping. These trees had been used to provide shade to visitor’s parking and amenity areas, as well as to enhance the habitat for less-robust plants and various types of indigenous birds and insects.
During the site design, we also kept in mind that in this part of the world, the optimum orientation would be East-West. That orientation alone decreased the solar gain on the exterior envelope of the building by 53%, which had a large positive impact on the cooling load.
Here’s the final outcome of the site:
This is the first post on the process behind the engineering of Stacey. There will probably be 6 more; energy efficiency, water system, apartment systems, daylighting, natural ventilation, and combined building systems. So, stay tuned!