Square Footage Off On Floor Plans, MP Issue?1880
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|tydowning private msg quote post Address this user|
|Today we received our first complaint in over 200 MP shoots of the square footage being off. We use a reputable service to convert the MP data into accurate PDF's for agents, and after checking with our service, and doing our own measurement test in the MP backend, Matterport is actually at fault.
The home we shot was off by 200 square feet total. Has anyone else had this issue?
We are worried that several of our past shoots are off, which could land us in a lot of hot water...Have any of you used a floor plan service only to find out that MP was not the 99% accurate as they say?
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|mwaychoff private msg quote post Address this user|
|Having provided manual site survey residential renovation drafting for many years I personally am uncomfortable enough with precision of MP camera and accuracy of MP floorplans that I will NOT be using them for anything more than diagrammatic representation of approximate room sizes, proportions, and adjacencies. The MP floorplans are great for interactive photo gallery navigation marketing. I have not been able to use them for overall square footage takeoffs nor accessibility renovations.|
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|craigsauer private msg quote post Address this user|
|I've wondered this as well. I intentionally avoid estimating total square footage from the floor plans I create (and have created) to try to avoid liability issues. I include dimensions on the floor plans, but I put a big disclaimer on them that I hope encourages people to take them with a grain of salt.
But I'm interested in the general issue of computing square footage, and it sounds like you know how this is supposed to be done. Are closets counted? How about staircases?
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|3Dwalkmethru private msg quote post Address this user|
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|I am staying away from that service, not worth the liability. \|
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|jscottsmith private msg quote post Address this user|
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|On the other hand...
I hear what everyone is saying, but that hasn't been my experience. Not only do I use it regularly for schematic floor plans, I've actually used it several times to create architectural as-builts. Of course, I put all sorts of disclaimers out there (as I would if I hand measured it), but I have been quite confident in my results. Anyone else had it work? :P
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|Jamie private msg quote post Address this user|
|You will get a slight variance with matterport measurements to actual measurements, generally by 95-98%. Remember they are going off what they can see, and they use a standard thickness for the walls. We (Nth America) are using the ANSI Z765 Standard, so the exterior walls are included in livable space.
Here is an example for you
1 level with an interior dimensions of 47'1" x 30'4" = 1500 sq ft with a standard wall thickness of 6 15/16" (this is a standard 2x6 (actually 5.5" wall with a 3/4" plywood exterior wall and 1/2" drywall. (math doesn't add up, but that's how it works
If the walls are increased (and generally the slab/foundation as well) to 10" (brick/slab walls) it then becomes 1541 sq ft. Multiply this over 3 levels and you have 123 additional sq ft, but the same interior dimensions.
This is where the outsourced floor plan model falls down unless you tell them if the wall thickness is different.
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|ccctucker private msg quote post Address this user|
|This was talked about in a thread a long time ago. The scanner isn't designed for fine measurement in inches, but in feet. Most of the things that can alter the number is based on the infrared. If the light is bright, the points are collected at different distances, causing the mesh to take an average of distance over several points. If they are off on both opposite edges, that could double the error rate. I tell people you can measure for carpet, bit not for counter tile.|
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