In two minutes, Becky Wong's inflatable house takes shape. It's a place for her two boys to work off their boundless summertime energy.
"Do you like it?" Wong asked her four-year-old son, Eric.
"I love it!," he answered.
She bought the backyard unit for her son's birthday last year in hopes that other neighborhood families could enjoy as well.
"It looked like a really fun activity that could have a lot of kids taking turns, having fun," said Wong.
The inflatable house goes up so quickly and easily that some parents leave out an important step: securing it to the ground.
Wong used the plastic stakes that come with her bounce house.
Some recommend going further.
"Get good metal, steel stakes. That will probably be your best option," said Casey McFadden of Bouncin Bins, an inflatable house rental company in the Portland area.
The company rents out large houses and play areas, some 64 feet long.
"We have an obstacle course, slides, all kinds of stuff," said McFadden.
He said they use long, metal stakes to secure the houses on dirt or grass, and 50-pound sand bags on a hard surface.
His advice for parents?
"I'd urge them to get the right equipment to stake it down and make sure it's not going anywhere," said McFadden.
That could mean putting aside the plastic stakes that came with your backyard bounce house and buying metal ones instead.
Wong said there is another crucial safety issue: parents keeping watch, as the kids slide, fall and bump each other on the bounce house.
Research from the National Children's Hospital showed as many as 30 children per day going to the emergency room because of injuries related to bounce houses.
"The more kids, the more supervision required," said Wong. "It's not, 'Great, we'll go have our drinks, coffee, whatever, and let the kids take care of themselves.' The more kids there are, the more problems that can happen."
Safety experts recommend parents post an adult at the bounce house the entire time kids are using it, to monitor for safety, number of children playing on the house, and weather conditions.
Some said 15 mph winds can be too much for some backyard bounce houses.
"If the parents can be outside with the kids the whole time, enjoying it with them, then, if they're the right age, this might a great toy," said Wong. "But you've got to be safe. It's not a leave-them-to-play-by-themselves kind of toy."