Building Physics: A Hat & Radiation

Objective: To demonstrate the principle of radiation and how solar radiation can be obstructed simply and effectively in a building

Outcome: Students understand that Shading devices are a simple, cheap and effective way of blocking solar radiation.

Materials: A hat

Prerequisites: None

Procedure:  

Step 1: Let the entire class go out on the college campus on a bright sunny day.

Step 2: Gather under a shade nearby, and let one by one stand under direct sunlight for 10 seconds

Step 3: After 30 seconds, let the student try on a hat for another 30 seconds.

Step 4: Once everyone has tried, discuss about the change of feeling before and after the wearing of hat, 

Step 5: What was the principle at play when standing under direct hot sun? How did the hat help? 

Step 6: Summarise with the students that the hat acted as a barrier similar to a shading device to obstruct radiation and subsequent heat gain.

Step 7: Talk through with the students how shading devices are a simple, cheap and effective way of blocking solar radiation and heat gain, instead of using materials like low Solar Heat Gain Coefficient (SHGC) glass.