Currently, there are no laws governing how square footage should be measured. ­

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­One of the most important factors to consider when buying or selling a house is square footage because it helps determine the market value and therefore the price of a home. Currently, there are no laws governing the way square footage is measured and surprisingly it isn't as straightforward as you might think. Therefore, it becomes the responsibility of the buyer to learn how a home's square footage has been measured and it is the seller's responsi­bility to represent the size of the home accurately.

It wasn't until the mid 1990s that a standard for measuring square footage was developed by the American National Standards Institute, also known as ANSI [source: Boddy]. However, the ANSI standard is only a set of suggested guidelines and there are other standards out there as well. These include the FHA/VA (Federal Housing Administration/Department of Veteran Affairs) standard and the Real Estate Commission standard [source: Propex]. While the ANSI standard is the most commonly used, you should always ask how the square footage of a house was determined.

­To determine the square footage of a house accurately, you'll need to know what should be included and what shouldn't. You'll also need to know whether to measure from the inside of the house or the outside. Aside from knowing the ins and outs of square footage in regard to real estate appraisal, it can also help if you decide to do any home renovations. For example, if you need to get an estimate from contractors to install new flooring, paint the exterior of your home or replace its siding, the contractors are going to want to know your home's square footage.

Read on to find out what square footage means, how it's calculated, and what is included when determining the square footage of a house.