Capital gains are taxable except that a capital gain of $250,000 or less from the sale of your main home may be excluded with the following provision. Generally, to be able to exclude up to $250,000 of this gain you must have lived in the home as your main home for a minimum of two years out of the last five. If you meet this requirement, then only the amount over this $250,000 exclusion is taxable. (On a joint return the exclusion limit is $500,000.)
This exclusion is tied to the home. If you sell the land on which your main home is located there is no exclusion amount.
If you have more than one home, only the main home qualifies for the exclusion.