Tools to facilitate your environmental designs. Understand the logic then use this piece-of-cake tool!

In a previous blog post, we discussed a high-level definition of thermal comfort to start aligning your designs to meet user needs. I showed you how to interpret the climatic parameters to design climate-responsive buildings.

But do you know you can count on tools to achieve thermal comfort to help you make your design decisions? Thermal comfort maps visualize humans' comfort in a given environment based on various climatic aspects. These tools include Victor Olgyay's bioclimatic chart (developed in the 1950s), which evaluates outdoor thermal comfort given temperature and relative humidity (see the figure below). So, you determine these parameters for your context, and the intersection lies within a range. You get recommendations for radiant heating or ventilation cooling, or your context is already in the thermal comfort zone.

A good practical example is available in the following YouTube video:

https://www.youtube.com/watch?v=43itjbrcUaQ

Olygay bioclimatic chart, developed by Prof.Bahaa Bakry (رحمه الله), 2009

For example, using the climatic data of Cairo city, temperature, and relative humidity, see the figure below, for each month represented in points (A, B, C,...,) or (1, 2, 3, 4,...) as you like. Then you link each point together, and you can find where your project is located (the red figure) so you can know what the guide to design (increase air, increase solar radiation, and so on) is. But remember, it is only scientific guidelines; you are responsible for optimizing your design strategy! Remember that you read this article; you are a conscious environmental architect!

Image source: (Abouaiana et al., 2012) https://www.researchgate.net/publication/344249300_Simulation_using_Envi-met_A_comparison_between_Cairo_University_Faculty_of_Engineering_PLAZA_and_6th_October_University_PLAZA

Another tool is the Psychrometric Chart, which uses specific climatic parameters such as dry bulb temperature, dew point temperature, relative humidity, and other factors. Likewise, the Olygay Chart, given the climatic parameters for a specific context, will help you find where your project is located.

Useful online tool: https://www.flycarpet.net/en/psyonline#google_vignette 

A very good practical guide to use it: https://www.youtube.com/watch?v=ZVXynRFeZQY&t=14s

Image source: https://commons.wikimedia.org/wiki/File:Psychrometric_chart_Engineering_Thermodynamics.png 

An example is shown below to set the analysis for Cairo city in June to find what design strategy recommendation should be followed. (Note: not all the climatic analysis shown is needed for this chart, but as much as you have data and are aware of different tools, as much as you design efficient strategy).

Image source: Ahmed based on (Abouaiana et al., 2012) https://www.researchgate.net/publication/344249300_Simulation_using_Envi-met_A_comparison_between_Cairo_University_Faculty_of_Engineering_PLAZA_and_6th_October_University_PLAZA

Do you feel that it is quite difficult? You had to understand the logic before using any tools. So, before you continue reading the article, please search for your city and send me your results in the comments!

No worries. I will guide you to a piece-of-cake tool called Climatic Consultant. It is a simple tool to:

The program and the EPW files are on the websites, shown in the figure below.

To use the tool, you need to start a new project, then select building type and units (like any software: AutoCAD, 3dMax, etc.), and finally, select the EPW file (you can directly download it from inside the tool). We selected, for example, El-Arish city in Egypt. You will see the weather data summary.

A very important issue is to determine the comfort model. The comfort models have different standards, each with its own criteria and measurements, but all aim to achieve acceptable thermal comfort for buildings' users. In this period of your life, you can select any model; maybe ASHRAE Standard 55 is fine.

But because we have a golden rule (understanding the logic and keywords = helps you understand the issue). So, the comfort models have different standards. Each has its own criteria and measurements, but all aim to achieve acceptable thermal comfort for buildings' users.

Okay, after you see the climatic parameters  (for interpret them see this article) yyou will finally see the psychrometric chart in detail (you can select a particular month, day, or the whole year).

As you notice, the yellow rectangle shows the percentage of the design strategies for a year. For instance, you need one-third of your design strategy to increase internal heat gain. which means it should be the prevailing strategy; also, you need 18% to dehumidify, and so on. Note: when we design for thermal comfort it is calculated by hour.

Stop now and answer my question related to Al-Arish City

Quiestion1: Do you need internal heat gain in summer? or in Winter? or in specific months?

Please answer my questions related to your City

Question 2: What is the design strategy for dehumidification?

Question 3: What is the optimal design strategy in your city in April?

I am waiting for your comments

Then, the next window will recommend general design strategies (if you follow 100% of the recommendations, you will achieve 100% thermal comfort).

Images source: extracted from Climate Consultant. Copyright (c) 2008, 2014 Regents of the University of California

Finally, please decide now if you can design environmental and climate-responsive designs. Can you make the users happy and satisfied with your designs? I do believe you can. Please start now!

Dr. Ahmed Abouaiana, December 05, 2024