Astros general manager Ed Wade said Oswalt's parents, Billy and Jean, were not injured. Wade said he expects Oswalt to rejoin the team by Tuesday. He's due to make his next start next Thursday.
Wade said Astros owner Drayton McLane offered his private plane for Oswalt to use, but Oswalt decided to make the 8-hour drive home instead.
"He just wants to make sure everything is all right," Wade said. "I told him to do whatever he needed to do. They lived in the house for over 40 years. He's got a ranch that's about 30 minutes away (in Kosciusko) that his parents can stay at, but 40 years worth of keepsakes and things like that, I'm sure it's really tough on his family."
Oswalt pitched seven innings in Houston's 4-3 win over Pittsburgh on Friday night. Houston manager Brad Mills met with Oswalt before he left.
"There are other things we need to get taken care of," Mills said. "He just pitched last night. That was an easy one. You've got to go. We always want them (players) to get things taken care of that they need to take care of. Because he's not going to be used again for another four, five days, that wasn't even a question."