The Sims 2: Pets

The answer is:

You can't.

In the Sims 2: Pets, you can't I mean. In some of the other Sims games, you can.

no thats not the point!
In PS2 Console there are Unlocked features such as:
1. Staircase
2. Open your own bussines
3. Other weather than raining AND
4. can NOT build Multiple Story Buildings.
so thats why 1 lot at the sims 2 PS2 is H U G E!
Still, at PS2, your memorycard can only hold "Insert MB Here", so you cant build multiple story high!, that needs like...4 or 5 Gigabites! why? because to prevent memory card from virus, the max size is 1MB-10MB. So thats why the reason they put "Fire Code Meter" at Right Screen. If you remove it, your memory card is corrupted and all of your saved games will crash, in other words, you need a new Memory Card!
I reccomended you playing the Sims 2 at PC, OfB is a great deal