Now that I increased the sq. meters on my house, how do I add the second floor???

[YvonneK]

Now that I increased the sq. meters on my house, how do I add the second floor???

[Lindal Kidd]

Is this a prefab house that you bought?  If so, you *might* be able to build a second story on it, if it is modifyable.  But matching the textures is going to be a real pain. 

You are better off buying a two story house, and putting it on your land in place of the old house.

If you are BUILDING your own house, adding a second story is easy.  Just rez another prim for the upper floor, and move it into position.  You can find excellent self-paced tutorials on using the SL building tools at The Ivory Tower Library of Primitives.