Engineering design challenge: Waterproof the roof

Engineers and geoscientists play an important part in protecting the public, including designing roofing materials to keep us safe and dry in our homes. The shape of our roofs also play a role in how they protect our living spaces from snow, rain, and wind. Materials engineers need to think about properties of roofing materials like absorbency, durability, and cost. Civil engineers need to think about structural design of buildings and how to make sure that they are safe to live under.

Your mission

Design a roof for a cardboard box that prevents the inside from getting wet when you pour water on it. The roof should maintain its structure throughout!


You should use objects you can find around the house to create your roof (some examples are below).

We recommend that you think about the different absorbency of different materials before building. Try pouring 2 cups of water over the top of your roof and make sure that your roof doesn’t collapse or leak.

Example materials

You can use these or any other materials you find around your house to work with:

  • Cardboard
  • Paper Towel
  • Styrofoam
  • Plastic bags
  • Reuseable grocery bags
  • Tape
  • Scrap fabric

Share some pictures of your creation online using the #NEM2021 or #NEGM2021 hashtag!