Simple Method to Do Climate Analysis for Architecture Students

It is mandatory for every architecture student to do a detailed climate analysis for all their projects. But why? And what information do you exactly need to go ahead with incorporating climate-related strategies in your designs?

Why Need Climate Study?

With a severe climate crisis on the rise, we need to make sure our designs don't contribute to it further. Building design that considers the local climate:

• helps reduce the environmental impact of construction and operation. 
• is better equipped to withstand extreme weather.
• optimize energy use by incorporating features like proper insulation, passive solar design, and natural ventilation. 
• lead to significant cost savings due to reduced energy consumption and maintenance.

Climate Analysis Step-by-Step

So how exactly do you get started with climate study? 

The most effective way to go ahead is to go to the site directly and experience the climate first-hand. Make a note of all the climatic and site factors and ask the local people nearby for their input as well. 

But that is not always possible or feasible. In that case, here's is another way:

1. Identify the climatic zone of your site/city
2. Download your site's climate file
3. Find out the different season and their months
4. Generate and analyze sun path diagram
5. Study wind patterns for each month
6. Study precipitation data
7. Identify factors contributing to comfort
8. Propose strategies based on your study

1. Climate Zone of Site

First step of climate analysis is to identify which climatic zone your site lies in. ECBC India categorizes the country into 5 zones- Cold, Composite, Hot-Dry, Temperate and Warm-Humid.

One way to find out which zone your site lies in, you can go to the ECBC climate zone finder site and select your city. The website classifies the city under a climate zone and also provides some basic design strategies that can be incorporated for that particular climate.

Sample Study- Hyderabad

• Hyderabad falls under the composite climate zone in India.
• This zone displays the characteristics of hot and dry, warm and humid, and cold climates.
• Some suggestions for passive strategies are also listed below.

2. Weather Data Files

A weather file is an extensive file containing daily temperature, humidity, wind, solar radiation, and precipitation at a particular location for an average year for a period of 30 years. For the city/area your site lies in, download the corresponding weather data file. If the data for your site is unavailable, choose the nearest available city/area file. 

These files are mostly available in .epw formats on several sites including EnergyPlus. The files can be opened and viewed in climate software like Climate Consultant or in websites like CBE Clima Tool.

Sample Study- Hyderabad

3. Classifying Seasonal Variations

It's easy to copy and paste all the climate charts from these sources to study and incorporate strategies for our designs. But what most fail to do is identify and analyse the seasonal changes that happen. For example, for the city of Hyderabad, the predominant wind direction is from the West. But Hyderabad needs most ventilation during the summer months, when it is the hottest, and for these specific months, the predominant wind direction is from the East. 

One easy way to identify the seasons and their months for a city is to:

• Take the city's annual dry bulb temperature chart and annual relative humidity chart
• Group them together to find similar patterns
• These vary according to the seasons but follow a similar looking pattern for each, making it easy to club months. 

Sample Study- Hyderabad

• Hyderabad has three major season- summer (from March to June), monsoon and windy (from July to October) and Winter (from November to February)
• Segregation of climate helps us design passively for each one, reducing the need for energy expenditure caused by active strategies. 

4. Sun Path Analysis

Sun path analysis for your site helps determine:

• Solar angles which can be used to determine the type and size of shading and window designs. 
• Amounts of radiation falling on each orientation to design passive strategies for building insulation.  

Sun path diagrams can be generated from softwares like Climate Consultant or websites like CBE Clima Tools and Andrew Marsh.

Click here to learn how to read a sun path diagram.

Click here to learn how to determine solar shading requirements.

5. Wind Rose Analysis

A wind rose chart tells you the wind direction of a particular city/area. It gives both annual and seasonal patterns. 

• The annual wind Rose chart gives the predominant wind direction for the entire year. 
• Specific seasons tend to have different predominant wind directions than the annual chart due to Most of the time, this season tends to be summer. 

The annual predominant wind direction can be different from the predominant wind direction in summer.

Sample Study- Hyderabad

• The annual wind chart shows the predominant wind direction to be West
• The summer months, which need natural ventilation, have a predominant wind direction in the East.

In all of the software, you can customize the wind rose chart for the months you want. Study the charts and design accordingly, to maximize natural and cross ventilation.

6. Precipitation Data

It is equally important to study the rain and humidity patterns for your site as well. This data decides your building's form, roof size, plinth height, material usage, and various other factors.

7. Psychrometric Chart

A psychrometric chart helps determine how much a certain passive or active strategy contributes to user comfort.

To learn how to read a psychrometric chart, click here

What the chart shows:

The Table

• The table in yellow shows all the strategies that might affect our site.
• The last four boxes in the table are active strategies while the rest are passive.

The Chart

• The psychrometric chart has colored boxes indicating a corresponding strategy.
• The x-axis shows dry bulb temperature and the y-axis shows relative humidity.
• The blue boxes show the most comfortable hours in summer and winter clothing.
• The green dots indicate comfort and the red dots show discomfort.

How to use the chart:

• Set hours, months, and temperature range on the left column.
• Click on the strategy that has more percentage of working for your city/site
• If the red dots turn green, it means that a particular strategy has a significant impact on user comfort level. Hence, we must implement it.
• Repeat this for all the strategies and try to achieve 100% user comfort 
• Try to maximize comfort through passive strategies as much as possible to save energy.

Sample Study- Hyderabad

8. Climate-Responsive Strategies

Softwares like Climate Consultant give strategies based on the factors you've selected on the psychrometric chart. However, these are just suggestions based on the values given. It is up to the designers to decide what will work and what won't according to our site context.

Give passive strategies for your design based on seasonal and climatic variations to achieve maximum passive comfort and cost reduction through energy savings.