How do I measure the square ft. on a two story house

Measure square foot on the upstairs and square foot on the downstairs and add them together.

Tick

Depends on what purpose your measuring the square foot of the home. In states like California for the purpose of selling a home the square foot represents living space. In other states like Tennessee the square foot represents the size of the home wich may include an attatched garage.

Also depends on the shape of the house. If it is square or rectangular, measure the front (or the back) and one end. Multiply. If the second story is same a first multiply by 2.

If some shape other than square or rectangular, you have to divide it up into rectangles, mentally of course. Measure one side of each rectangle and its adjacent side and multiply. Add up all of the rectangles.