crawl space Getting wire into house?

Putting a splice underground and not in a watertight enclosure is a little iffy, to say the least. I'd say to leave a loop, say 3 feet, of cable on both sides for repairs if needed. Wrap the whole splice, and a few inches onto the cable with a couple of layers of high quality electrical tape, 3M 88+, then add a layer of coax seal, or other self-amalgamating, tape past the electrical tape, then coat the whole thing with a few coats of rubber based paint well past all the tape. This may seem like overkill and a half but if water/moisture gets in there it'll mess things up pretty badly.
 
Putting a splice underground and not in a watertight enclosure is a little iffy, to say the least. I'd say to leave a loop, say 3 feet, of cable on both sides for repairs if needed. Wrap the whole splice, and a few inches onto the cable with a couple of layers of high quality electrical tape, 3M 88+, then add a layer of coax seal, or other self-amalgamating, tape past the electrical tape, then coat the whole thing with a few coats of rubber based paint well past all the tape. This may seem like overkill and a half but if water/moisture gets in there it'll mess things up pretty badly.
Use die-electric grease on the connections.
 
Use die-electric grease on the connections.
YUP use dielectric grease on the connections. For my business, I always use a gel filled encapsulant and then 3M 88 tape the crap out of it, as water will eventually find its way in when buried.

When installing cables through a floor (like the original post) most codes require you to use fire block foam.

Typically, I will install a grey pvc conduit (its easier on the cable sheath) and use fire block or greet stuff to seal the hole