How do I stop people opening my front foor?

[Tarraz]

My house is set to private but people can still open my front door and walk inside. How can I stop this so my door is always locked?

 

[derpydonkey]

Single click on each door and select "Set Security", then select whichever option you would like. Owner would be the most secure and prevent anyone but the three characters on that account from opening the door

 

[Tarraz]

Thanks