Design Journal Entry - Module 9 - HVAC System

Journal Entry For
Module 9 - HVAC Systems

Overall HVAC system strategy

The museum is located in a hot and humid climate zone, so HVAC is crucial. While I tried to include passive cooling techniques, I may have increased dependence on conventional techniques. However, there are several windows and openings throughout the project that provide plenty of fresh air. Much of the natural ventilation, however, is restricted to the areas that are not display spaces, as the humid air would not be the best for the artworks/display items in the museum.

The building is, on a high level, divided into two parts of an infinity, one for the private, smaller spaces, and the other has large display spaces for the public. The ceiling height is constant in most places, except when there are transitions, like corridors, atriums, double height café, etc.

I started with placing spaces on to the floor plan and correcting the heights, and then creating a space schedule. The space schedule was an easy way to correct space type properties for each space. The space heights are restricted to the ceiling heights, because ultimately, only the space below the false ceiling will need to be ventilated.


Heating strategy and implementation

In terms of source for artificial heating, electricity is used for the heating system in this building. A central air handling unit is present on the first floor in the mechanical room, and then local ones in ceiling on the left and right sides of the building on every floor. This way, the entire building is covered. There are diffusers/grills present throughout the building for supply and return. The supplies are towards the windows, since most temperature changes happen there. 24x12 and 12x12 rectangular ducts have been used, along with 12x12 diffusers.

Cooling Strategy and implementation

One big design decision I made to reduce heat in the building is to orient the building such that the number of opening towards the south and west are minimal. The majority of light and ventilation happens from the east and south sides. For passive techniques, the building orientation again plays an important role. Also, the shape of the floor plates is such that it provides self-shading, much like the roof overhangs that the module specifies.


Plinth/first floor cutaway:


Second floor cutaway:


Third floor cutaway:



  1. The complex building design itself is tough to design for, especially in that climate zone. For e.g., the sloping roof leads to several different heights, and make it tough to set space heights; floor plates shift in each floor, so the mechanical system design cannot be a copy from the previous floor and has to be strategized each time.
  2. Some of the spaces are not too well-defined in terms of boundaries, such as having double or triple heights. This increases the load on the HVAC system, and also makes analysis difficult.
  3. Even though natural ventilation is preferrable in most spaces, since there are large exhibition spaces, it may not be prudent to have natural air flow through the building. It needs to be controlled, and used in certain spaces only. This increases dependency on the mechanical system.
  4. The supply and return ducts were clashing with each other, and with the structural model, so I had to look for clear routes to draw the ducts. Also, the flex ducts do no appear in 3D if there is not at a certain distance between the duct and the terminal, so I had to move many terminals in 3D.