# RE: Quick/Easy Question for Seismic List

• To: seaint(--nospam--at)seaint.org
• Subject: RE: Quick/Easy Question for Seismic List
• From: Charles Espenlaub <Cespenlaub(--nospam--at)martinaia.com>
• Date: Wed, 22 Mar 2000 16:13:46 -0500
```The 0.02 is unitless.  If multiplied by feet the result is feet.  If
multiplied by inches, the result is inches.  Therefore 74'-0" x 0.02 =
1.48 ft.

On the side, it seems odd that a three story building is 74 ft tall.

Charles F. Espenlaub, III, P.E.
Martin-Espenlaub Engineering

-----Original Message-----
From: Ritter, Mike [mailto:mritter(--nospam--at)lgt.lg.com]
Sent: Wednesday, March 22, 2000 3:18 PM
To: 'seaint(--nospam--at)seaint.org'
Subject: Quick/Easy Question for Seismic List

Colleagues,

Please help me with a quick question.  I am looking at some calcs
prepared by another engineer, who calculated the allowable story drift
for a three story building from BOCA and ran the number based on story
height in inches.  In other words, the building height is 74', but he
used 888 inches.  This gives the allowable story drift to be
0.02(888")=17.76".

I've always used the story height in feet, which would give an allowable
drift of about 1.48".  I was going to show my colleage the code section
which says story height is in feet, but could not find it in BOCA, UBC,
SBC, Farzad Naiem, or any other text books.  Does anybody have a
reference section showing that the story height, by definition, should
be in feet?  I know it must be there, but I'm in a rush and can't find
it.

Thanks again for the help!

Michael Ritter, PE

```