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How do you measure? ANSI rules included

By
Real Estate Appraiser with Estimation Nation Corporation

 

When measuring Do you:

  • Deduct 6 inches for brick facades or use measurements from the interior or exterior?
  • Round to the nearest inch, 1/4 foot, 1/2 foot, foot?
  • Eliminate one level of the stairway and open spaces?

It all adds up (or down) and when it comes down to it, it's all about how the county or developer (or whatever reference you are using for the houses in the area) has decided to measure the comparable property spaces.   Even my state board has varying opinions within the office. This is the reason I give a 50 square foot leeway for comparable properties to subject.

Here are some ANSI (American National Standards Institute) 'suggestions'.  I say suggestions because it is a voluntary guide rather than a direct rule.

Always start by measuring the outside of the house.
  • Begin measuring from any corner and work your way around the house. Move counter-clockwise so the numbers on your tape will be right-side-up.
  • Measure the exterior of the house to the nearest inch or tenth of an inch. Measure from the exterior face of the walls. Include any features that are on the same level as the floor, such as chimneys and bay windows. Do not include the thickness of any corner trim pieces or greenhouse windows that don't have a corresponding floor level. * Use the 100-foot tape for long wall sections and the 25-foot tape for short sections.  
  • If there are stairs, include them on every level they serve.
  • When there are openings to the floor below, subtract the opening from that level.
  • For split-level designs, measure each level. You can lump multiple floor surfaces into one level if they are within two feet of each other.
  • Exclude any areas, such as porches and converted garages, that are not finished or heated the same as the rest of the house.

Basements

The ANSI standards make a strong distinction between above-grade and below-grade floor area. The above-grade floor area is the sum of all finished square footage which is entirely above ground level. The below-grade floor area includes spaces which are wholly or partly below ground level.

Attics

Level ceilings must be at least 7 feet high, and at least 6 feet 4 inches under beams, ducts and other obstructions. There is no height restriction under stairs. If a room has a sloped ceiling, at least one-half of the finished floor area must have a ceiling height of at least 7 feet. Otherwise, omit the entire room from the floor area calculations. If a room with a sloped ceiling meets the one-half-of-floor-area-over-7-feet requirement, then include all the floor space with a ceiling height over 5 feet.
 

Detached Rooms, Guest Quarters

According to the ANSI standards, finished areas which are not connected to the main residence by a finished hall or stairway must be listed separately. If you have to leave the house to get to the room, it's not part of the finished floor area.

 

I realize there's a bit more than just measurement information in there, but I found some of the 'standards' interesting and perhaps useful in the future.  Although ANSI is not 'the law', it is the closest thing I could find to it. I will have to assume that developers, tax assessors and other 'measuring professionals' use the ANSI guide and measure likewise (although not necessarily going counter-clockwise everytime).


Chris Bradford
Bradford Realty Group - McDonough, GA
Bradford Realty Group: Henry County, Georgia

I have found that most real estate professionals, even appraisers, have never heard of the ANSI standards and few that have adhere to them. Although they were a topic of great discussion when first introduced, any discussion or even acknowledgment of them pretty well petered out until recently.

Personally, I like the ANSI standard. Although I may not 100% agree with every aspect of it, it offers a consistent way to measure which yields consistent results. By using this standard, everyone is comparing apples to apples.

In the commercial end of things, BOMA (Building Owners & Managers Association) and other trade groups offer standards for measuring. Although their standards are goo, I wish ANSI would step into this arena also.

-Chris

Commercial Property, Clayton County, Georgia - Bradford Realty Group

Feb 19, 2007 01:31 PM
Sara Goodwin
Estimation Nation Corporation - Portland, OR
Portland, Oregon Appraiser

Hi Chris -

That may not be why they are so rarely used... no t many people have heard of them! 

I can't say I agree with every 'rule' ANSI has either, but at least it's a standard for everyone to start at.  Measurements can vary  200+/- square feet on a larger 2+ story house depending on what set of rules the developer, county assessor, appraiser uses -

Sara

Feb 20, 2007 02:51 AM
Nick M.
Certified Residential Appraiser- West Palm Beach Real Estate - West Palm Beach, FL
Realtor-Appraiser in West Palm-South Florida Real Estate Appraiser
Hey Sara, interesting topic & getting down tot he basics. we dont have too man finished attics and almost no basements. 2 of the near 5 counties also have floorplans.. :))  I measure on the outside with a roller wheel, either clock or counter clockwise, depending on the property, accessibility, etc. I prefer to do the side that has least amount of plants, A/C units, etc. I note to the inch, and normally round down on walls with lots of stucco (round down about 1/2 foot on a 50 foot stretch).  I suggest that the footprint is what is measures, rather than the space inside. All properties are measured as such around here, so it only makes sense.  stairways: i leave the opening on the 2nd level and include the entire 1st level and note stairs. This normally matched public rec around here.  thanks for the insight in appraising in another part of the country. I'll stay here for now ;)  see ya.
Feb 25, 2007 12:07 AM
Anonymous
Karin Adams

Dear Sara,

When doing an appraisal, how do you write up a below ground level when only part of the home is below ground and has a main entrance going into the house? The below ground level has the main kitchen, a bathroom, living room, dinning room, bedroom and sun-room. How can you be fair in the evaluation if you use the ANSI standards and count this as only a basement, when clearly it is so much more? Is there a right way to write up an a appraisal that will be fair to the home owners?

Nov 28, 2007 01:44 AM
#4
Sara Goodwin
Estimation Nation Corporation - Portland, OR
Portland, Oregon Appraiser

Hi Karin -

I ran into a similar situation a couple of weeks ago where all the bedrooms and full bathrooms were downstairs in the daylight basement and so the main level didn't have enough amenities to consider it a complete house. 

Fortunately in this instance, there were comparables in the immediate neighborhood with similar floor plans.  In this case I was able to add the subject and comparable basement square footed in with the above ground GLA and I wrote a long addendum statement explaning why.  Due to having neighborhood comparables with basements that commanded the same values as their neighbors without basements definitely helped.

As I understand, there are also areas in the US that value basement space at the same value as above ground GLA.  In such markets, I would imagine that appraisers would understand this and write up their conclusions to value accordingly.

Nov 28, 2007 03:19 AM
John Fariss
Fariss Appraisal Services - Bakersfield, CA
Appraiser - Bakersfield, CA

My measuring methods are fairly close to this standard. I use a laser and a pocket pc so I can only get so precise. The laser will measure to a 1/100th of a foot, but the sketching program will round to the nearest 1/10th of a foot. This combination seems to be very accurate since my calculations come very close to matching county records.

Nov 28, 2007 05:09 AM
Sara Goodwin
Estimation Nation Corporation - Portland, OR
Portland, Oregon Appraiser

Ah... John - so your county records are actually accurate!  You lucky bum -

So... do you measure stair space on each level or just one?  I go back and forth on this one... In fact I believe I saw where ANSI suggests measuring all levels where stairs are even open space.  I'll have to investigate that again.  Ummm, I guess all I had to do was look at the post again to figure that one out.  My bad... all levels for stairs.  Strange, I think.

Nov 28, 2007 09:09 AM
John Fariss
Fariss Appraisal Services - Bakersfield, CA
Appraiser - Bakersfield, CA
I measure the stairs on one floor only, so after I'm done measuring the outside I'll go subtract out any open areas including stairwells.
Nov 29, 2007 04:42 AM
Anonymous
Darek

Sara, are you still using a tape measure?..measuring from outside could be very painful process,

And especially in a very cold climate such as Canada climate. A very simply way and accurate to do it is to measure from inside the building using laser tools and add thickness of the exterior wall.Draw on site using mobile cad station or tablet PC, this way when you leave the site everything is accurately measured up and drawn up.

We have been doing that for years, we measure commercial, retail, residential, industrial buildings and provide accurate floor plans and area calculations

 www.precisionplusfloorplans.com

Nov 25, 2008 06:56 AM
#9
Sara Goodwin
Estimation Nation Corporation - Portland, OR
Portland, Oregon Appraiser

Hi Darek -  

I'm now spoiled with my Disto!  I love it - When I was using measuring tapes, I would have two in my bag... one for indoors and one for outdoors because the outdoor tapes would get incredibly dirty especially in the wet season (approximately 9-11 months in Oregon) -

With the Disto it's usually easier to measure from the inside, but then I add in wall width the keep up with ANSI -

As a professional measurer I'd love to hear if you choose ANSI -

Nov 25, 2008 07:33 AM
Anonymous
Darek

Hi Sara, sorry for the late reply i was out of town.

Yes, Disto cuts short 1/2 of the measuring process, its really worth the invest. However you also need an advanced drafting software to provide accurate floor plans and square footage calculation.

Yes.We use BOMA/ANSI 1996 Z 65.1 measuring standards for office buildings

As for industrial we use BOMA/SIOR 2004

Sara, do you measure houses only?..or large buildings such as office and industrial buildings?

Looking to hear from you

Darek

www.precisionplusfloorplans.com

Dec 15, 2008 02:45 AM
#11
Anonymous
Harold Goldman

Good topic, Sara

Measuring from the exterior surfaces will result in a larger house than the architect's drtawings.  In frame houses the drawiings measure from the outside of the foundation/wall framing which does not include the thicknesses of the exterior wall finishes that may may add an inch or so all the way around the house - sheathing, wall finish materials. 

The area of the stairs of one floor deductiion:  The deduction should really be the area of the lower run of stairs with closets or storage under the stair excluded from the deduction.  The only part of the stair deductin should only include the parts of the run of the stair that would be counted twice.

HUD as a rule does not count basement space as habitable space. If a bedroom does not have proper light and ventilation, the room can not be included in the gross living area.  The following requirements apply to the valuation of below-grade rooms: Basement areas are allowed as GLA provided windowsills are not be higher than 44 inches from the floor, windowsill must have a net clear opening (width x height) of at least 24 inches by 36 inches and window should be at ground level (I suppose that eliminates window wells).

Disto is a good thing except for outside corners  What's a simple way to to measure to them?

Keep up the good work         ~H

  

 

 

Aug 16, 2009 08:35 AM
#12
Anonymous
Bert Cox

Hi Harold, I'm a real estate appraiser in Texas and do mostly single family homes.  My metal clipboard doubles as a measuring prop just as much as a clipboard when I measure the outside of homes. I position it against the brick/structure wall and it works great.  If for some reason it's difficult to get to the far side of the edge or time inefficient I can sometimes bounce it off a fence or object directly behind the far edge of the wall, take the measurement, then when I'm on that side of the building measure from the edge of the wall to the first object I bounced it off of and then subtract.   Many times this can eliminate walking back and forth unnecessarily.  This method can also be used if there is a window opening or object fixed to the house I.E. electric box, or many times a fence, then I just use the plus/minus feature on the disto.  If there's no other way to get the measurement, I simply guess ;-)

Feb 10, 2010 12:13 PM
#13
Anonymous
Christian van Dyck

Aloha,

you forget one thing. Since we mainly use comps as a measure of how much a property is worth, and we have to rely on what an MLS listings states as GLA (sometimes not the same as county records) we end up comparing a known fact with an unknown fact believed to be true. A buyer decides to buy a house believing that the stated GLA is correct. Even if he finds out later that it is not, the final sale  price is likely not changed much, so a price is set for a certain GLA. But we do NOT know exactly what that comps true GLA is. Were stairways counted on both floors ? Is it permitted or not ? Have county records been updated ?

Basement ? What if its built on a slope with one wall below grade. Or were every level has a wall below grade ? According to ANSI then its ALL a basement... 

So all this effort to count every square inch of a subject and be as exact as possible is somewhat pointless when we cannot know for sure that what we compare it with is done according to the same rules.

If county records state a house wall is 12 feet, and I measure 11.5, It is 12 feet in my eyes. Besides, on a house that worth lets say $500K, a few SqFt more or less will have little impact.

So save your efforts and look at the BIG picture, what does the market say ? More important than ANSI... ANSI is for architects and builders, who do NOT compare anything. For us appraisers, it's only a guideline.

Christian
Hawaii

Jun 07, 2010 09:32 AM
#14