Questions: What is the main difference between balloon and platform framing?

The answer is the second one: In balloon framing, studs extend from the foundation to the rafters.

Explanation:

1. Attic framing is vastly different.

   • Incorrect. This statement does not address the main difference between balloon and platform framing.

2. In balloon framing, studs extend from the foundation to the rafters.

   • Correct. In balloon framing, the wall studs run continuously from the foundation to the roof, which is a defining characteristic.

3. Platform framing is used only for single-story houses.

   • Incorrect. Platform framing is commonly used for multi-story buildings, with each floor built as a separate platform.

4. Balloon framing uses only $8^{\prime}$ long studs.

   • Incorrect. Balloon framing can use studs of various lengths, depending on the height of the building.

Summary: The main difference is that in balloon framing, the studs extend continuously from the foundation to the rafters.