An NBC 5 investigation has found that local building codes, concerns about cost and a lack of information prevent people from building homes that could give them additional protection from tornadoes.
In most parts of Texas and across the country, local codes only require that homes and businesses withstand a 90 mph gust.
Some of the twisters in the April 3 tornado outbreak in North Texas packed winds of 130 miles per hour or more.
One of the tornadoes touched down just a few blocks from Mary Jensen's Kennedale house.
"I was scared," she said.
Jensen rode out the storm in a safe room in her garage. It's designed to survive a 250-mph, EF-5 tornado. She installed the safe room in March but said she wishes she had put one in five years ago when her home was built.
"As far as I can remember, it was never an option. 'Do you want a tornado-proof room, a storm shelter?' I don't think that was offered," she said.
Tim Jackson, of the Home Builders Association of Greater Dallas, said most local builders know about shelters and other building techniques to make homes more wind-resistant. But they don't always include those items on the lists of amenities they offer.
"I can't say that they're actually pushing storm rooms," he said.
"I guess on the downside we could probably do a better job of selling it as a need instead of a materialistic thing like granite countertops or hardwood floors," Jackson added.
Fort Worth builder Don Ferrier builds safe rooms using layers of plywood and steel. He turns closets into Federal Emergency Management Agency-certified shelters designed to pass the 250-mph test.
Why don't more builders do that?
"One is, they've never done it," Ferrier said. "I think that's part of it, and the other part is, the homeowners haven't asked for it and they're having to compete on cost most of the time."
A safe room such as the ones Ferrier builds can add about $5,000 to the cost of a home. And builders often fear they will lose the sale if their house costs more than one down the street.
Tim Marshall, a meteorologist and one of NBC 5's Storm Trackers, is also an engineer who investigates storm damage for an Irving engineering firm.
He said he believes builders should at least show buyers what can be done to make homes safer, such as adding metal straps to the frame of the house to make it stand up to heavier winds.
"We're talking about maybe $500 or $800 to strap the roof down to the wall, the walls down to the bottom plate, as well," Marshall said.
Marshall said he would like to see more builders go beyond the minimum building code. In the April 3 tornadoes, he saw homes that suffered damage he would expect from much larger tornadoes.
"Your house is only as strong as your neighbor's," he said. "If your neighbor's house isn't built well, you';re going to get hit by your neighbor's."
The builders association said buyers also have a responsibility to ask questions, and if buyers start asking for more safety features, the market will respond.
"I think they talk about initially, but when they get down to the actual cost, they decide to use the money elsewhere or not put it in at all," Jackson said.
Jensen said the cost of her shelter was worth it.
"You're saving your life and the life of everybody you love," she said. "You can't put a price on that."