Absolutely, why not? Is it a vented crawlspace or non-vented crawlspace? Do some searches on youtube. They do a good job of showing you exactly what to do, and give suggestions and ideas. There is a vapor barrier that should go down on the dirt-floor to prevent moisture whisking up to the floor causing water/mold issues. If it's non-vented you can insulate the walls of the crawlspace foundation. Insulate between the floor joists as well. It all helps....
The Following User Says Thank You to cbaur88 For This Useful Post:
You can do searches on this site as well, as there have been a good number of threads related to crawlspace insulation. Without actually seeing it, it's hard to say for sure, but given the type of foundation and the age of the house, it is very likely that you could make a measurable dent in it with simple caulking, spray foam insulation, and rigid insulation, at the perimeter of the joists. In fact, it is very likely that if you were to go down there during the day, and have someone turn the lights off for a minute or two, you may very well see numerous points where your heating costs are escaping you.