The numbers can lie, and here’s why

Buyer beware: Don’t put too much faith in the advertised size of homes for sale. Sellers, realty agents and builders sometimes put a little marketing spin on the square footage to make a home seem larger than it actually is.

But this is less commonplace than it used to be. Uncertainty over accuracy and the risk of lawsuits have forced real estate brokers and home builders to exercise more caution when they represent size to prospective buyers.

Realty agents today generally quote the square footage they obtain from the seller, the tax assessor’s database or a property information service that packages public-records data. And agents typically include warnings and disclaimers that they haven’t independently verified the data.

As a general rule of thumb, houses are measured using the exterior walls, while condominiums are calculated by the space inside the walls. But that’s where the simplicity ends.

Individual builders and various entities employ differing standards, so the safest bet for reliable square footage usually comes from the county assessor’s parcel information. During a sale, an assessment of home size frequently occurs during the lender’s appraisal.

One egregious example of misrepresentation of square footage would be a two-story home calculated at twice the dimensions of the foundation, even though the second story is smaller than the first story or some rooms on the first story have cathedral ceilings that extend to two stories.

Other questionable calculations count a screened patio, an unfinished garage or an attic crawl space as part of a home’s square footage. The size of a fireplace or bay window might be added to beef up the figure.

New-home models can be deceptive if they include upgrades that aren’t part of the base-priced home. Such options as a bonus room, enclosed patio, sunroom or breakfast area might increase the square footage of the model but not be part of the plan a buyer is purchasing.

On resale homes, the reliability of data sources depends on whether the original information was accurate and whether it was updated if the house was remodeled.

In one attempt to standardize the measuring of square footage, the National Assn. of Home Builders Research Center in Upper Marlboro, Md., published “Square Footage -- Method for Calculating: ANSI Z765-2003” in 1986, according to Thomas Kenney, the center’s director of engineering sciences. The standard is approved by the American National Standards Institute, a private nonprofit organization that promotes, administers and coordinates voluntary standardization systems.

The standard can be used to determine the square footage of any proposed, new or existing single-family house of any style or type of construction and relies on measurements taken outside the structure. It doesn’t consider room dimensions, nor does it address whether measured space is habitable or whether any additions were constructed with the required permits or in compliance with the required building codes. The standard isn’t meant to be applied to condominium or apartment units, although Kenney said there has been some discussion about development of a similar standard for that purpose.

Appraisers, real estate agents, builders and government zoning officials have asked about the standard since it was published, but the center hasn’t kept records of who is using the standard or how widespread its usage is throughout the country. Standards typically don’t contain a notification process, Kenney said.

The Los Angeles County assessor’s office doesn’t use the standard in compiling its data. Bonnie Oliver, an assistant assessor at the agency, said she wasn’t familiar with it. She attributed this to the fact that a trade group developed the standard.

“We’re not governed by the builders association,” she said.

County assessors measure the perimeter of a house to calculate the square footage, Oliver said. “We draw every nook and cranny. The appraiser starts at one corner and goes all the way around.”

The method is at least superficially similar to the ANSI-approved standard for measuring houses.

“The easiest ones are rectangular, but a lot of them have recesses or they jig and jog,” she said. “Sometimes they have to eyeball it.”

To keep their records up-to-date, assessors could re-measure a house at any time, but re-measurement typically is triggered when the office receives notification of a building permit or other evidence that the home has been enlarged.

Potential home buyers sometimes try to compare home values on a price-per-square-foot basis. And although price-per-square-foot calculations may be helpful as a general gauge, buyers should be wary of relying heavily on such figures, which don’t take into account the condition of a house, the location within a neighborhood or tract, whether a house has been upgraded or remodeled, the desirability of the floor plan and other unquantifiable or subjective characteristics. A small house that has been well maintained, offers a view and has been remodeled could be a better value than a larger one in the same neighborhood.

Another reason buyers should be wary of a price-per-square-foot measurement is that most of the value of a property is in the land.

When Jo Pitesky and her husband, Bill Freedman, bought their Studio City home six years ago, Pitesky created a spreadsheet that used the sales price and lot size of tear-down houses in the area to calculate the land value of the lots on a per-square-foot basis. She then subtracted the computed land value from the sale prices of better-condition homes to determine how much they were worth on a per-square-foot basis.

The spreadsheet was a key component of the couple’s decision on what to offer, but to this day, Pitesky is not quite sure how large the house actually is. The seller’s agent quoted a size of 2,500 square feet -- a figure later confirmed by a carpet cleaning service that charged by the square foot.

Other buyers don’t put much faith in square-footage measurements. Deborah Alexander, an attorney, has been hunting for a larger house as a trade-up from the small Culver City condominium she purchased 14 years ago. Her goal is a home of at least 1,200 square feet on a lot of at least 5,000 square feet; however, the “presentation” of the house and the backyard are as important to her as size, she said.

“I use the numbers as an initial indicator, but I won’t rely on them. If the house is 1,000 square feet, I won’t bother,” she said of her forays to look at houses. “If it’s in the ballpark, I will go to the house. I’m not going to measure it foot by foot, but I’m going to see how it feels.”

Alexander’s distrust of square-footage figures might be the result of a 22-square-foot mystery. Her condominium was listed as having 882 square feet when she purchased it, but an appraiser later found 904 square feet of space.

“I converted a closet into a hallway room,” she said. “I think [the appraiser] included that in the square footage and maybe it wasn’t counted originally.”

Alexander is philosophical about the size.

The larger figure, she said, “is better resale value for me, but it didn’t really matter when I bought it.”