Did I set this up correctly - house with negative equity

[Alex Zuroff]

Hi,

I'm trying to set up GnuCash for the first time, and I'm not sure I set up
our house correctly.  I'm trying to follow the examples in the "Capital
Gains -> Account Setup" section of the tutorial.

I have the following accounts set up:

Assets:Fixed Assets:House:Cost
Assets:Fixed Assets:House:Unrealized Gain
Income:Unrealized Gains

In the Assets:Fixed Assets:House:Cost account I entered a transaction for
the original sale price of the house.  I set the transfer account to
Equity:Opening Balances since the purchase was made several years ago.

In the Assets:Fixed Assets:House:Unrealized Gain I entered a transaction
with a "Decrease" amount for the amount that our house has gone down since
we bought it (we live in California).  The transfer account for this
transaction was Income:Unrealized Gains.  This leaves both accounts with a
negative balance, which makes sense since the value has in fact gone down.
What doesn't quite make sense is that the Equity account didn't change - is
the Equity account only supposed to change value when I sell the house and
realize the loss?

Is this the correct approach to take even when our house is upside-down?

Thanks,
Alex