There are many ways to protect your house. But you already know that. Similarly, there are likely many ways to do what you are asking about. Here is one way. This depends on the router in your house. As such, it only works when the Internet appliance is connected to your home's wifi. Some routers allow you to block IP addresses. Some can do this on a client by client bases. I have even seen routers that turn these features on and off depending on the time of day. You could conceivably block facebook IP addresses for a particular client of the router based on the MAC address of the client. That said, who said facebook only uses 1 IP address? They probably have a set of IP addresses or portals to the web. So you might have to block them all. If you google for "facebook ip addresses" you get this:
The following IP address ranges belong to Facebook:
220.127.116.11 - 18.104.22.168.
22.214.171.124 - 126.96.36.199.
188.8.131.52 - 184.108.40.206.
That's a lot of IP address. Hopefully your router will accept IP address ranges.