Practical way to splitting CAT5 for 1wire?
I used telephone sockets and splitters purchased at a €2 store without trouble. 


CAT5 loops through the telephone sockets.
Cut a phone lead to the required length and solder the wires onto the 1-wire sensor. 




Figure 1. Be aware that most telephone leads have the plugs oriented with the latch on the ribbed side of the cable (or the same side of the cable) which means that colour sequence is opposite at each end.

I strongly suggest that you pick one pattern and throw the other end away or you will go slowly bonkers soldering and debugging.



Figure 2. A 1-wire shield for the Raspberry Pi simplifies the protocol. Source: AB Electronics.

I recommend the extra cost of a shield for this as it removes any timing issues which will arise if you try to connect directly to the Pi GPIO. See the link.

I had no problems with 1 m stubs from the telephone sockets with half a dozen sensors on a 25 m run.