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Floor PlansSQFT

Square Footage Dispute - HELP!3438

StevenHattan private msg quote post Address this user
What are your thoughts on square footage difference. Do you charge, let it go, refund, give a credit.

Do you allow a percentage of discrepancy? Does it make a difference if it's a first time client or a repeat client? Does it matter on the size of the home or if other services are involved.

My repeat client was off 283 sf or 14.1% off. (He reported 2,000 sq ft and it was measured at 2283 sq ft).

Whoever answers gets a free small box of Rice a Roni (chicken flavor). You just have to pay $4.99 shipping and handling.
Post 1 IP   flag post
Cleveland, OH
CLE3D private msg quote post Address this user
I tell clients that the total comes from myou total scanned square footage so it doesn't really matter what they tell me, other than for an estimate before I start the project.
Post 2 IP   flag post
Gibbsboro, NJ
Radie842 private msg quote post Address this user
Haha. I charge in a range. So it's up to 1000 sqft and up to 2000 sqft and so on. If it's a repeat client. I'd let it go as long as it doesn't become a habit.
Post 3 IP   flag post
jward private msg quote post Address this user
Square Footage is normally public record, so it should be black and white... Sure you might scan extra outside if you're a baller, but why fus over incorporating that. I don't have the volume yet to be charging by sq.ft.
Post 4 IP   flag post
Integratedman private msg quote post Address this user
If this is a repeat client..I would politely bring this up...let the client know that you will offer this at n/c..but you are aware and present in a manner that you are offering good will and value..and look long term..ensuring if client was pulling a fast one..you are aware and will charge next time out..
Post 5 IP   flag post
uniqueceo private msg quote post Address this user
Don’t risk losing repeat business over a minor difference, absorb the cost while politely stating the obvious.
Post 6 IP   flag post
StevenHattan private msg quote post Address this user
I wound up charging the client. Back in my previous life as a server in a restaurant I sometimes 'forgot' to charge something trying to be a nice guy. It never made a bit of difference. In hind site, it was stupid to do that...on many levels.

No one wants a box of rice? haha
Post 7 IP   flag post
Blue-Sketch
Founder
New Orleans, LA
PetraSoderling private msg quote post Address this user
This is a difficult topic. I've been in these conversations a lot. There can be any number of reasons why MP scan (and subsequently our 2D Floor Plans) differ from what the owner or public records state.

- thickness of outer walls. MP measures floor space to the inner wall. We add a 6" thick outer wall in the Floor Plan - this is the ANSI guideline - but if the outer wall is in fact thicker, then the owner would have a larger sqft in their records
- apartment buildings may add general spaces like elevator shafts, corridors, etc. to the apartment size
- Public records may not have been updated if any renovations were done in the house. Also with an older house that was measured before lasers came about, the public record may not even be that accurate
- Realtors should only include heated living space when they give the sqft out to home buyers. Whether the garage is included or not makes a big difference, for example
- per level, stairs should be included with the area they descend
- Pipes, ducts etc utility space that is hidden inside walls (even an outer wall) should be included
- Any hidden closets that were not scanned would be missing from your number
- etc.

When you consider all of these, and potentially other factors, a 14% disagreement is not so big (IMO).
Post 8 IP   flag post
WGAN
Basic
Member
Seattle
kjoman private msg quote post Address this user
We had a client whose home turned out to be almost twice the size than the public records showed so you cannot always count on that. It was one of our first shoots with a first-time client so we let it go but it taught us a lesson (plus one member of our team was hiding in the bathroom & broke the toilet seat to smithereens). Also, as a broker, doing market analysis, I've found the public records off a lot (so much remodeling without permits).
Post 9 IP   flag post
GeorgeK private msg quote post Address this user
I would let it go... and tell them I will catch them next time... and make it clear next time it is an actual square footage fee.

Send the Rice and I will get you the handling later...
Post 10 IP   flag post
Jamie private msg quote post Address this user
It's something you need to address or you will seem unreliable to the client. This is why errors and omissions insurance is required to work with some realtors. If a homeowner sues because of this, they come after you and the realtor. Chances of this happening is almost zero, but always something you want to avoid.

Are you calculating the square footage, or is matterport?
Post 11 IP   flag post
StevenHattan private msg quote post Address this user
@Jamie if I told you I'd have to kill you. ;-)
Post 12 IP   flag post
StevenHattan private msg quote post Address this user
I try to make decisions based on how I would perceive things in the other person's shoes.

I took five extra pictures (offer 25 and give 30 so it minimizes the chance I have to go back out) and didn't charge the client.

As a client I wouldn't bat an eye about it and look at the person as a true professional that is running a consistent business.

I certainly would never entertain the idea of shopping elsewhere over a few bucks because I know it's hard to find good service providers.

Great feedback though.
Post 13 IP   flag post
WGAN
Standard
Member
Bon Secour, Alabama
Chemistrydoc private msg quote post Address this user
@SteveHattan

I get into this all the time here for a variety of reasons - 1) indolent tax appraisers, 2) agents who can't work a tape, and most importantly,what I actually scan! In many cases, I like to throw in outdoor scanning, if the light and the client permit, so that increases the area i scan. I've often used a tool like the one on howner.com to show the area scanned (a receipt of sorts) when I get someone who questions my figure.

To avoid this, I often have guessed high (10% over) on the area, and quoted the job with a discount of 10%. Funny how folks never bat an eye at a discount!

Cheers,

Keith
Post 14 IP   flag post
Jamie private msg quote post Address this user
If you are reporting a square footage to an agent, it needs to follow the ansi code (north America, not sure if this applies elsewhere) especially if the agent is using this information to sell the property. If you just guess, you should let them know you are doing this.
Lots of agents or client have no idea how to calculate square footage and it's always a good opportunity to let them know how to do it
Post 15 IP   flag post
WGAN
Standard
Member
Bon Secour, Alabama
Chemistrydoc private msg quote post Address this user
@Jamie

I guess I didn't make myself clear. I NEVER step into the "official sq ft" discussion. I use it only when charging the client. If the client wants to pay me to determine an accurate sq ft to report, then I will bring out the laser and do a proper floor plan, but charge accordingly.

Cheers,

Keith
Post 16 IP   flag post
Jamie private msg quote post Address this user
@Chemistrydoc ahh ok. That's fair enough, I thought it was for accurate information
Post 17 IP   flag post
iGUIDE
Founder/CEO
Kitchener, Canada
Alex_iGuide private msg quote post Address this user
Since iGuide provides floor plans with square footage report and room dimensions (see example report http://www.goiguide.com/showcase), iGuide operators have to discuss measurement results quite often. Here are few things to keep in mind that we recommend to iGuide operators.

1. Ask the agent where those numbers came from. Often they come from tax records and may be outdated since the building may have had few additions since then. Yours came from your own measurements.

2. Ask what those numbers include or determine that yourself based on what that number is stated to be. Non-living space such as garages, cold cellars are typically excluded. Levels below grade (basements) are excluded as well. You also need to know the difference between exterior and interior area to account for all discrepancies. See Kevin's presentation on Residential Measurement for more info on the topic of how space is measured in real estate - https://www.youtube.com/watch?v=-p2zLg3RbYo

3. Know what you have included in your numbers (e.g. have you included the basement that you scanned)?

4. Know the accuracy of your measurement equipment and how it affects computed square footage. While Matterport cites 1%, this is not the whole picture. Say it is 1% at 5ft, it then will be twice that at twice the distance, i.e. 2% at 10ft. This is the nature of triangulation technology that MP camera uses. Next, when you compute square footage, the error in % doubles again. So 1% uncertainty in linear distance leads to 2% uncertainty in computed floor area (try multiplying 1.01 by 1.01).

5. When 5 people measure the same space they will come up with 5 (maybe slightly) different results as any measurement has measurement uncertainty due to equipment and operator errors.
Post 18 IP   flag post
Premium
Member
North Palm Beach, FL
hometakes private msg quote post Address this user
I tell agents that we charge based on the number that they enter into MLS. Theres not one agent out there that I know that doesn't want to make sure that the homes is as big as what it is. They would hear it from the seller if they undersized it; "My house is 2400 under air, not 2250. We added the utilty room and thats why it doesn't show on the tax records, they never updated it."

Not had one house that scanned bigger than what was in the MLS. And if one did, most likely the agent would thank you when you told them that they would be paying a little more than your quote as you just brought them great news that they can tell the owner of the home.....
Post 19 IP   flag post
Frisco, Texas
Metroplex360 private msg quote post Address this user
Quote:
Originally Posted by StevenHattan
What are your thoughts on square footage difference. Do you charge, let it go, refund, give a credit.

My repeat client was off 283 sf or 14.1% off. (He reported 2,000 sq ft and it was measured at 2283 sq ft).


If you're using MP2SQFT as a tool for calculating SQFT -- usually you will end up with LESS SQFT than an agent is claiming (as, mentioned by others, it will only report the surface area as calculated by Matterport's servers from the OBJ file).

Some ways that things end up with more SQFT --

#1) Garages tend to not be included in MLS SQFT
#2) Outside areas should not be included -- sometimes scanning by a windowed area will add SQFT to a model if the window is not marked and trimmed.
#3) You have a garage conversion, 'sunroom' or extension to the home that wasn't properly reported by the seller/agent.

Quote:
Originally Posted by kjoman
(plus one member of our team was hiding in the bathroom & broke the toilet seat to smithereens)


... what?

Quote:
Originally Posted by hometakes
I tell agents that we charge based on the number that they enter into MLS.


Same.
Post 20 IP   flag post
Premium
Member
North Palm Beach, FL
hometakes private msg quote post Address this user
@metroplex. Thats the fairest way. They are never going to knowingly under size the home.
Post 21 IP   flag post
Blue-Sketch
Founder
New Orleans, LA
PetraSoderling private msg quote post Address this user
@Alex_iGuide I like your detailed answer here but one thing I'm not sure I agree. You wrote:

"While Matterport cites 1%, this is not the whole picture. Say it is 1% at 5ft, it then will be twice that at twice the distance, i.e. 2% at 10ft. "

I would think 1% is always 1% in a linear line. 1% of 5 feet is 0.05 and 1% of 10 feet is indeed double 0.1 but it is still just 1% of the 10 feet, right.

I agree with you on the added complexity when multiplying for square footage.
Post 22 IP   flag post
iGUIDE
Founder/CEO
Kitchener, Canada
Alex_iGuide private msg quote post Address this user
@PetraSoderling Petra, that is an excellent question, thank you for asking as I suspect other people may be wondering about it too.

Matterport camera uses structured light (random pattern projected by IR laser projector and viewed by IR camera) and that is a type of triangulation technology. The IR camera measures angle to each dot in the random pattern and uses the distance between the IR camera and the IR projector (camera baseline) to solve the triangle and compute the range to the target.

When the math is done for such a measurement set up, it will follow that the (absolute, in inches) error in range measurement grows as square of the measured distance. As a side note, it also follows that the error decreases if a longer baseline is used. So, when you express the measurement error as a relative error in percent, that is, divide the error by the distance, you obtain that the relative error is not constant and also increases with the distance. But that increase is now linear and not quadratic. Again, this statement applies to triangulation technology only. As another side note, InsideMaps and RealVision (Toursler) measurement methods are triangulation-based as well.

The iGuide camera, on the other hand, uses a time-of-flight technology in its laser scanner where the measurement error does not depend on distance. For us it is 1.5" out to 30ft which is the nominal measurement range of our camera, though for walls that are reflective enough (not dark), the measurements out to 90ft can be reported.

That hopefully clears up the confusion. Let me know if I can help more.
Post 23 IP   flag post
Blue-Sketch
Founder
New Orleans, LA
PetraSoderling private msg quote post Address this user
Wow this is very very interesting. Thank you @Alex_iGuide

Matterport says nothing about this on their support page

https://support.matterport.com/hc/en-us/articles/212629928-How-accurate-are-the-dimensions-in-Matterport-models-

I'm starting to feel slightly uneasy as I'm relying on Matterport's own statement with our floor plans.

I'm going to ask them about this.
Post 24 IP   flag post
iGUIDE
Founder/CEO
Kitchener, Canada
Alex_iGuide private msg quote post Address this user
These things are hard to explain and it is easy to lose people after the first couple sentences and it can get even more complicated.

To take it to the next step - how do you get the best out of the MP camera? The answer is to not let the error run away and limit the distance between scans. That way you can somewhat slow down the linear growth in measurement error. It does come with an added cost of increased time spent on-site to do those extra scans and this directly affects the photographer's bottom line.

Since the distance between the scans is a choice made by a photographer in each house differently, it may be difficult for MP to provide a uniform error number that will cover all cases.

They also mention on their support page that temperature and de-calibration may affect measurement accuracy. The reason for this is that the camera is factory-calibrated and relies on knowing exact angles and distances between IR sensor and IR camera and those values being constant throughout lifetime of the camera. Those values can be affected, however, by temperature changes (temporary effects) or mechanical shock to the camera (may be temporary or permanent changes).

Such changes are a pain to deal with. Our previous generation camera (IMS-4) was triangulation-based too and to deal with such issues we developed an in-field calibration procedure where photographer can bring the camera back in spec at home by taking a few pictures. With our new IMS-5 camera it is a non-issue anymore and it does not require any in-field calibration.
Post 25 IP   flag post
Blue-Sketch
Founder
New Orleans, LA
PetraSoderling private msg quote post Address this user
Here is Matterport's response: "We're aware of the issues with % accuracy with measurement. We don't provide specific details about how the measurements are accomplished. We'll include your note in our weekly meeting with the engineering teams to ensure the feedback is processed by the correct team here at Matterport."
Post 26 IP   flag post
Frisco, Texas
Metroplex360 private msg quote post Address this user
Well, here's what you can do.

You can use MP2SQFT and experiment with the data that Matterport stores and compare to real square feet.

When I made the original MP2SQFT, I added a tool where you could draw on the generated floorplan to fill in the blank areas. I found that for the apartments that I was scanning, I got correct dimensions within 10sqft. That's pretty darn accurate as far as I'm concerned.

While I don't disagree with Alex on anything - what I'm truly wondering is what the margin of error tends to be in the wild. If a case study was done - what would be the most outrageous example of error margin? Of course -- disqualify wacky tours of exterior areas and focus on interiors only.
Post 27 IP   flag post
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