All other things being equal (square footage, apartment condition, layout, etc.), how much more is a higher-floor apartment worth?

That's the question under discussion on StreetEasy.com, where efforts to assign an exact number--in the $5k-$10k range?  1% per floor?--come to no clear conclusion, and some even argue that apartments that are too high up (say, above the 15th floor) suffer from impaired river views and should get a demerit instead of a boost.

We asked real estate appraiser Jonathan Miller of Miller Samuel to explain how he correlates dollar figures to floor numbers. 

"When it comes to floor level adjustments, we separate floor height and view into two separate amenities," he says. "The floor level adjustment reflects the actual and perceived changes in natural light, street noise and security."

The adjustment is bigger when comparing a second-floor apartment to a first-floor apartment.

Depending on market conditions, he says, "a typical adjustment might be 1% per floor before considering view differences. That's 1% of the price of the unit you are comparing it to."

Once a property breaks the roof line of the adjacent building, a view adjustment, in addition to floor level adjustment, would likely be warranted, says Miller.

"Of course if you live in a walk-up, the reverse logic applies," says Miller. Lower-floor apartments are worth more than higher-floor cousins, and the floor level adjustment would likely be higher than 1%.

Walk-up apartments above the fourth floor are often subject to more restrictive financing so that would another 'break' to be adjusted for, he says.

Related:

How to make or break your appraisal

A buyer's options when the appraisal is too low

The true value of an on-site storage unit

Will converting my half-bath into a laundry room hurt my resale value?

I fell for the view, then shut the curtains

I can't use my 43rd floor terrace--but the closets are amazing

Note: BrickUnderground articles occasionally include Featured Partners and Resource Directory members when their expertise is relevant to the story.