[SML] Ganging seats

[Bill Conner]

So longish reply, but I was recently researching this for a client,
and felt the codes were not as explicit as they should be.  Summary,
International Building Code is unclear, and simply does not require
the seats in your space (I'm assuming 200 or fewer seats) to be
fastened to the floor.  Exceptions 3 and 4 below being noteworthy. The
Life Safety Code on the other hand, is a little more specific, and
requires seats be ganged in grouped or 3 or more.  More important is
perhaps that you should be concerned about seats on tiers - platforms
- and the ability for them to slide off.  Based on my experience -
calls from layers - it happens often enough to be a serious concern.
Code excepts below for your use.  Ultimately, of course, the local
official or authority has the final say.


>From 2015 IBC:
1029.14 Seat stability. In a building, room or space used for
assembly purposes, the seats shall be securely fastened to the
floor.
Exceptions:
1. In a building, room or space used for assembly purposes
or portions thereof without ramped or tiered
floors for seating and with 200 or fewer seats, the
seats shall not be required to be fastened to the floor.
2. In a building, room or space used for assembly purposes
or portions thereof without ramped or tiered
floors for seating, the seats shall not be required to
be fastened to the floor.
3. In a building, room or space used for assembly purposes
or portions thereof without ramped or tiered
floors for seating and with greater than 200 seats, the
seats shall be fastened together in groups of not less
than three or the seats shall be securely fastened to
the floor.
4. In a building, room or space used for assembly purposes
where flexibility of the seating arrangement is
an integral part of the design and function of the
space and seating is on tiered levels, not more than
200 seats shall not be required to be fastened to the
floor. Plans showing seating, tiers and aisles shall be
submitted for approval.
5. Groups of seats within a building, room or space
used for assembly purposes separated from other
seating by railings, guards, partial height walls or
similar barriers with level floors and having not
more than 14 seats per group shall not be required to
be fastened to the floor.
6. Seats intended for musicians or other performers
and separated by railings, guards, partial height
walls or similar barriers shall not be required to be
fastened to the floor.

>From 2015 LSC:
12.4.9.2.3 Seats and footrests of grandstands shall be supported
securely and fastened in such a manner that they cannot
be displaced inadvertently.
12.4.9.2.4 Individual seats or chairs shall be permitted only if
secured in rows in an approved manner, unless seats do not
exceed 16 in number and are located on level floors and
within railed-in enclosures, such as boxes.

12.4.10.2.4 Individual chair-type seats shall be permitted in
folding and telescopic seating only if firmly secured in groups
of not less than three.

(You may feel that typical black box/flexible theatre seating is not
"grandstand" nor "folding and telescopic" seating but I think you
would loose that argument in a court as the definitions in the codes
seem a lot like portable platforms and chairs.  Also, in the absence
of something more specific, its likely to get stuck in one of these
categories.  Worse, now you were told loose seats on risers were a
hazard.)

-- 
Bill Conner Fellow of the ASTC