Getting the correct square footage is a constant conversation with our photographer and realtor clients. There are several factors that come into play
- ANSI Z765-2003 standard for single family residential buildings
- Regional Real Estate Commissions and their guidelines
- MLS listing guidelines regarding property and lot sizes
When we draw a floor plan we are always using source material given to us by a photographer, realtor, or a home owner. We use our best judgement to redraw as accurately as we can, however it should be clear that floor plans like the ones drawn here at Blue-Sketch are for marketing purposes only and we cannot take any responsibility of the dimensions or measurements.
The most accurate floor plans are produced when the source material is laser measured, or in the case of Matterport, measured digitally with the camera’s depth sensor.
While some of the Matterport scans can be a bit lopsided we can usually find from the overall floor plan view one or more rooms which are perfect rectangles and have a clear walls. This is where we take the measurement (see the yellow line).
While this is done visually by a human, we are using a iMac 27″ with a 5K retina display and can drop the measurement points exactly on the wall pixels. Matterport is scanned from inside the house, so the end of the wall is the inner side of the outside wall.
We then start to “trace”, drawing the floor plan on top of this original source file. We are using 6″ outer walls as instructed by ANSI and the other guidelines, creating an accurate representation of the dwelling.
Once we’ve drawn outer walls we measure the outside of the house, again according to standards, and exclude openings in floors, any non-heated areas such as balconies or porches, and any possible unfinished areas.
We rely on our customers to give us information of any spaces that would be underground, less than 5′ tall, or otherwise not considered heated living space.
The result is what we think as accurate as square footage as can be give the input we receive.