When you’re comparing house plans, one of the most important features you’ll look for is the zone of the floor plan – the size of the plan – measured in square feet.
But I’ll let you in on a little secret about “square footage”: it’s not measured the same on every house plan. That means two house plans that appear to be the same area may not really be!
Does that make much of a difference when you’re choosing a plan? I bet yes! Just a 10% difference on a 3,000 square foot plan could unexpectedly cost you tens of thousands of dollars!
apples to apples
Builders, architects, real estate professionals, bankers, auditors, and appraisers often count square footage differently, to better suit their particular needs. House plan services also vary in their area calculation protocols; To accurately compare floor plan areas, you must ensure that areas are counted equally.
Generally, builders and real estate professionals want to show that a house is as big as possible; allowing them to quote a lower “cost per square foot” and making the home appear more valuable.
Appraisers and county auditors generally only measure the perimeter of the house, a typically very rough way of calculating area, and call it a day, while architects break the size down into components; first floor, second floor, porches, finished ground floor, etc.
To arrive at an “apples-to-apples” comparison of home areas, you need to know what is included in the totals. Does the area include only spaces with heating and air conditioning? Does it include everything “inside” (I’ve seen garages included in some areas of the plan!) or just “living space”?
Up and down, inside and out
But even when you’ve figured out exactly which spaces are included in the area calculation, you’ll still need to know how. volume is counted, and if the total is grid square meters of gold Fat.
Gross area is the total of everything inside the outside edge of the house perimeter; the net area is the same total, minus the thicknesses of the walls. In other words, the net square footage is the part of the floor that you can walk on; the brutes include the parts you can’t walk on.
The difference between the two can be as much as ten percent, depending on the class floor plan design. A “traditional” plan (with more differentiated rooms and therefore more walls) might have a 10 percent net-to-gross ratio, while a contemporary plan might have only 6 or 7 percent.
Similarly, larger houses tend to have more walls, because larger houses generally have more rooms, rather than just larger rooms.
You will probably never see the volume of a house plan listed on a plan site, but the number that represents the area of a floor plan often depends on how volume is counted. Typically, the “upper area” of two-story rooms (hallways, family rooms) is not counted as part of the floor plan. Also, stairs are only counted once. But not always: check how volume is counted to make sure you know how big the plan really is.
Plan services that design their own plans will have a uniform area (and volume) policy, but services that sell plans on consignment probably won’t.
How does the plan designer or service you are purchasing calculate the plan size? Sometimes that information is on the service’s website or book, and sometimes you have to call them to find out. But you should definitely find out – it can make a world of difference to the cost of the house you ultimately build!