I am wiring a old house that has never had electrical service and have a question about what type of wire should be used. This crawl space is exposed to weather, but all wiring would be on inside floor juices.

The typical Romex is called NM-B cable and can only be used in dry locations.

I believe your situation calls for NM-C, which is allowed in dry, moist or damp locations.

It makes life much easier to use wire that is labeled for your use. However, when I worked for a company that made cable, the only thing we changed when we went from one grade to the other was the print wheel, all the stuff, sunlight resistant, underground feeder, etc used the same compound. We didn't even change the print wheel for different brands. All that was printed on the wire was a UL code they could track us down from. The different grades did have different tests they had to meet. So keep the authority having jurisdiction happy and find some of the right cable.