WATCH: Dad builds backyard roller coaster

TORONTO – A man built a roller coaster in the backyard of his San Francisco-area home because, well, he couldn’t think of a reason not to.

“I started building the coaster because Lyle, my son, asked me if we could, and I couldn’t think of a good reason to say no,” Will Pemble explained to CBS San Francisco.

Lyle, 10, discovered his love for roller coasters after taking his first ride last summer in New Jersey.

“I decided to ride it because I thought it would be fun, and then I thought there are more and better roller coasters out there, so I started doing research on them,” Lyle told the TV station.

Lyle’s father used the six-week project as a learning tool for his son.

“The mathematics, the physics, the science, the really hard thinking, there needs to be something on the other side of that math that’s worth slogging through that math,” Will explained to CBS.

“If there’s a coaster on the other side of the ‘how many feet of track we need,’ then all of the sudden the word problem gets done really fast.”

The only thing missing?

“A loop,” Lyle said.