In short, if your house increases in value, the money you owe vs the things that you own changes in your favor, resulting in less risk for the bank. It is therefore likely that a bank (not necessarily the one who currently has your mortgage) is willing to give you better terms/interest based on the new circumstances, and your current bank will therefore make an effort to be competitive.
I’m too young to own property in my life time and don’t understand the renegotiate mortgage meme.
How come the rates are lower if the house goes up in value?
In short, if your house increases in value, the money you owe vs the things that you own changes in your favor, resulting in less risk for the bank. It is therefore likely that a bank (not necessarily the one who currently has your mortgage) is willing to give you better terms/interest based on the new circumstances, and your current bank will therefore make an effort to be competitive.