Published on: January 19, 2023

No matter the season, heating and cooling systems play a key role in creating comfort in every home. Did you know that drafty homes can lead to higher energy use and utility bills? This is because homes with old windows or gaps and cracks around the windows and doors can let warm air escape in the winter and cool air escape in the summer. This makes their heating and cooling systems work harder to maintain the indoor air temperature.   

Luckily, identifying these gaps and cracks can be done pretty easily. Challenge your students to find air leaks in their homes by making their own draft detectors using common household items. Here’s how: 

What You Need

  • A coat hanger  
  • A facial tissue 
  • A paper clip, hair clip, or clothespin 

How To Complete The Test

Step 1: Use the clip to attach one end of the facial tissue to the coat hanger. Part of the tissue should be able to hang freely.  

Step 2: Hold your homemade device next to your windows and doors.  

Step 3: When the device is held steady in the path of a draft, the tissue will flutter, indicating an air leak. If the tissue stays still, the windows and doors are probably airtight. 

Step 4: Repeat this test on all the windows and doors in your house. Make a note of which windows or doors may have an air leak. 


Once your students have completed the test, have them share their results with the class and discuss what they can do next.  

Students who discover air leaks should tell their parents or guardians right away. An adult can help easily fill in the gaps and cracks with sealants and weatherstripping.  Sealants, like caulking, can easily fill gaps and cracks that don’t move, such as around fixed windows. Weatherstripping is generally adhered to exterior doorframes and operable windows, so that when the door or window is closed, air is unable to leak through the opening. A thorough job of sealing and weatherstripping will reduce drafts, increase indoor comfort, and help save on heating and cooling costs.

Having your students make their own draft detectors? Encourage them to watch our TikTok video on how to find air leaks around the home. And if your students are in Grade 9, they can complete this test as part of our comprehensive student-led home energy review. Get in touch to receive free home energy kits for your students to complete their home energy review! 

For more great lessons about energy efficiency, check out our other available resources on Generation E’s website.