Bes-Based Building Envelopes Design. Using LadyBug+HoneyBee.
NOTE: The patches available for download use Honeybee & Ladybug 0.0.64. Using different version could cause problems. In that case it is strongly recommended to rebuild the patches with the owned version.
BES BASED BUILDING ENVELOPES DESIGN
Using Grasshopper /LadyBug+HoneyBee
As a complex system the building envelope is made of many parts and components with different characteristics in shape, construction materials and functions coming from different requirements. One of these requirements is related to the energy consumption and users’s comfort where the architectural envelope plays the important role of balancing energy flows between buildings and the surrounding environment. In the early design stage, energy simulation can be an useful tool to evaluate different options and to address more effective solutions tailoring materials and technologies according to indoor and outdoor conditions. In fact and even at the conceptual level, energy simulation can offer to designers evidences on which parts are more or less energetically solicited; which are the most useful part for sun harvesting; the coldest surfaces that could required a better insulation.Therefore, energy simulation can support a design that allocate resources in a differentiated and more appropriate way interpreting the real vocation of the architectural elements.
2.3. Thermal Surfaces Vocation – PATCH DOWNLOAD – [Explanatory video on this patch ]
This patch makes it possible to identify, thermal behaviors of a building previously modeled as a mass, defined in their functional space program, and their heating/cooling set-time.
Energy balance flows of the building envelope is extracted and the Average Outer Surface Temperature (°C) is also visualized as a colorized model. In addition, the program displays, for each zone, the normalized Thermal Load Balance and a list of the following thermal results : total loads; cooling loads; heating loads; electric light loads.
In order to run this evaluation properly it is required to observe the following recommendations:
1. GEOMETRY Design your building with simple masses in metric unit (!). Since Energy Plus does not work well with non-convex casting surfaces it will report errors. Although this problem will not affect the thermal analysis (only the lighting analysis) it is advisable to trasform all volumes into convex entities by breaking them up into a set of smaller components that are each convex. For example, an L shape should be decomposed into two simple volumes or surfaces.
Once the masses are completed, import them into the Rhinoceros software (or design them directly into this software) and places the building ground floor on the zero level of the Rhino canvas. If the building includes some underground volumes or it rises on pilotis, move the relative floors under or above the zero of the Rhino canvas. Afterwards assign all the volumes to the Brep component of Honeybee and set these masses using “multiple breps” and “internalize data” so you can delete or hide the architectural volumes in Rhinoceros while preserving masses in Grasshopper. This last action allows you to reopen the Grasshopper file without having to redraw or import them again.
For a more accurate analysis it is also necessary to consider and import schematic masses representative of the building context!
Assigned to each thermal zone its functional program and the heating/cooling set point in accordance to the environmental indoor requirements.
2. COMPUTATION. Carry out the computation in order to verify the building behavior with the HVAC system contribution. To operate in this way check the “ISconditioning” node is set to “True”.
Test specific analysis periods setting the hot/cold weeks of the year previously collected in the “Climate and Comfort Simulation” module and read outputs in order to get information about: which is the coldest / hottest surface ; where cold / hot surface are located; which is the most critical ones. In integration Average Inddor Surface Temperature (°C), and Surface Energy Flows can be displayed from the ” Read Surface Result” component in order to have more informed knowledge of the envelope condition in different period of the season and days.