Transcript for Houston furniture store owner opens stores to Harvey victims

shelters across Houston. Stadiums, convention centers, churches embracing the suddenly homeless, and one man opened the doors to his store. An act of generosity that made perfect sense. Ab’s Matt Gutman is inside that story. Matt? Reporter: What could be a softer crash pad than a furniture store that has model bedrooms? Not every store would be happy with evacuees sprawling all over thousands of dollars worth of merchandise, but not everybody is mattress Mack. Reporter: This is Jim mcingvale, better known as mattress Mack. Do you want your furniture? We’ll save you money. Reporter: A beloved local businessman with a texas-sized personality. And since 1981, he’s owned the high- end gallery furniture stores in Houston. Soon after the winds started blowing, the 66-year-old Mack went from selling to giving. We’ve got lots of bed we’ve got lots of food, we’ve got water. Reporter: Offering a free port in the storm. We have both buildings as shelters during this horrible time. Reporter: Mack had plenty of takers. He says a lucky few hundred came on their own. Others rescued by his own delivery trucks. We sent them out, picked up about 200 people. They were stranded on bridges, they were stranded in convenience stores, they were walking through the water with snakes and alligators. Reporter: They all found shelter at Mack’s two Houston stores and warehouses where they could recover from their struggles on plush beds and couches with high altitude price tags. We said to hell with profits, lets take care of the people. This is the right thing to do. That’s the way I was brought up. I just thought we would go to a shelter and it would be really hard times for us right now. But now, being here, oh, I’m so relaxed. Reporter: This has also become a crash pad for the National Guard company on break. These $12,000 beds quite the upgrade from their standard issue cots. And he is not concerned about any wear and tear. The furniture is made to be sat on, flipped on, slept on. Use the product. It ain’t going to hurt it. Reporter: To you going to sell it afterwards? Absolutely. We’ll have a floor model sale or something. When they said gallery furniture, I was like, they gotta be joking. Reporter: This is Carroll. She’s here with her daughter and two grandsons. They’ve called this living room display home for the past three days. You were in Katrina. I never thought we would experience the same thing. But we did. Reporter: Back then, she was trapped on the 6th floor of a building in New Orleans. We got rescued by the coast guard. They took us to the convention center in New Orleans. Reporter: How many people were there? Oh, hundreds and hundreds. It was horrible. Reporter: This time, she was rescued by the fire department, who brought her to Mack’s place. He didn’t have to do this, and he made it so comfortable. When I left home, I left home without some of my medications and some of my medical equipment and they supplied it. Reporter: Countless other buainesses are also stepping up. Bakery workers here stuck at work, stayed up all night baking bread to feed first responders. Restaurants giving away free meals to rescuers as well, and even air bnb teaming up with their hosts to offer up free rooms to evacuees. This is where we have all our dogs staying. Reporter: And back here at Mack’s place, doing everything they can to make their temporary guests comfortable. And for the adults, on the menu, not your typical “Riding out the storm” fare, thanks to donations from a local restaurant. What are you eating there? Prime rib and mashed potatoes. Reporter: Prime rib and mashed potatoes. The smiles here, contagious. It’s really, really good. Reporter: Mack’s stores have also become a neighborhood drop off for donations. Food, water, medicine and pet supplies for those who left everything behind. People have brought so much that we’ve been sending out to other shelters. Put the heavy stuff up top. We appreciate you doing this for us, my friend. Thank you so much. Reporter: Nearing his seventh decade, Mack himself literally worked 24 hours straight. And now, despite it all, his store amazingly is still open for business. Can you do both at once? Somebody said, “Are y’all still a shelter or a furniture store?” I said, “We can be both, its not an either/or proposition.” Reporter: Among the stacks of mattresses, we came across ruby hays reaching out to mattress Mack. My 84th birthday, right here. Reporter: You spent your 84th birthday here? Monday. Reporter: She says Harvey took everything from her, and Mack does something better than dry off her tears. We’ll give you a mattress for your birthday, how’s that? Oh, thank you. Gotta give you a birthday present. Happy birthday. Reporter: A true testament to the spirit of Texas. You got to love Mack, but what a team effort this has become, Matt. Reporter: This is incredible, you know, the chamber of commerce says $74 million have been donated to Houston but, you know, we spent is better part of two days here. Every couple of minutes, somebody with a pickup truck has rolled in with whatever they have. Extra paper towels, gra Nola bars, mountains of clothes that have been shipped off to another shelter and a lot of cleaning products. Anything to help people clean up and rebuild, George. It’s all going to be needed. Matt Gutman, thanks very much. We’ll be right back with more-this special edition of 2010 TWN. When we continue. We’re going to get you! The most incredible rescues. From a baby in an air lift basket, to about airman with his dog.

This transcript has been automatically generated and may not be 100% accurate.