Most people are surprised to learn that the second largest energy consumer in the home, after space conditioning, is water heating. Water heating uses more than 15% of the average home's total energy use. Because it is an out-of-sight energy consuming system, most forget about this major contributor to the home's energy bill. For quick savings, this is a great place to start because some minor changes that are fairly easy to make can make a noticeable difference in your energy bills.
You can square up a wall before raising it by measuring from opposite corners. Assuming that both the top and bottom plates are equal in length, and that both ends are the same, the wall is square when the diagonal measurements are equal. Adjust the wall as necessary, then keep it square with sheathing or with diagonal braces before raising it.