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Sorry, another frontage/open space question.
- Thread starter Sifu
- Start date
steveray
SAWHORSE
If the roads or parking lots are fire lanes, most likely
Yankee Chronicler
REGISTERED
From that image I don't know where the rear is and where the fences are, but the intent of the open perimeter allowance is that the building fronts on open space that is level enough and firm enough to allow firefighting operations. I would review with the fire marshal to determine whether the FD considers having to chop through a couple of fences to be "open" perimeter.
Paul Sweet
SAWHORSE
Firemen would have to be able to open the gates to consider it an open space for frontage purposes.
Sifu
SAWHORSE
- Joined
- Sep 3, 2011
- Messages
- 3,391
That is my thinking, but not well defined by code. I did one some time ago and they provided knox boxes at the fences so I went with it.
Yankee Chronicler
REGISTERED
My problem is that I've been through too many code cycles, and I "remember" things that aren't there any longer. At one time, either the code or the Commentary laid it out very clearly that to qualify as excess open frontage a space had to be accessible to firefighting operations and be accessed from a street or a posted fire lane. I just looked for that and I couldn't find it in a quick search, but it may be in one of the Commentaries -- or I may be remembering that from when we used BOCA (before there was an ICC).
Inspector 102
REGISTERED
Are you considering exiting provisions or allowable increase considerations?
steveray
SAWHORSE
FD knows how to get through a fence.....Does a fenced site have no open space?
steveray
SAWHORSE
I think what you are looking for might be in the definitions...
Yankee Chronicler
REGISTERED
Where? There is no definition of "frontage," "open space," "open perimeter," or "street frontage." If it's in definitions, it's well hidden.
Yankee Chronicler
REGISTERED
Looks like the best explanation is in the commentary to IBC 506.3.1. It's a bit lengthy, but here's the full explanation (all higlighting added for emphasis):
There is no requirement in the code that buildings have
at least 25 percent of their perimeter on a public way or
open space. However, in order to qualify for an area
increase, a building must have more than 25 percent of
its perimeter on a public way or open space having a
minimum width of at least 20 feet (6096 mm) (see Section
506.3.2). When the calculations are done, the maximum
percent increase for a fully open perimeter (full
frontage—the entire perimeter fronts on a public way or
open space) is 75 percent. Width is measured at right
angles to the perimeter walls, as set forth in Section
506.3.2, but open frontage is not the same as fire separation
distance. Fire separation distance, as defined in
Section 202, is measured to the centerline of public
ways or to an imaginary line between buildings on the
same lot. Open space can include the total width of the
public way as well as the total open space between
buildings on the same lot. “Public way” is a defined term.
If a structure is divided into two or more buildings by
fire walls complying with Section 706, the area modifications
allowed by Section 506 must be determined
based on each separate building within the structure.
This especially comes into play in determining
increases allowable based on frontage. The fire wall is
essentially the perimeter wall for that side of the building
and must be included in the total perimeter in calculating
the percentage of perimeter on a public way
or open space. Since there is another building on the
other side of the fire wall, this portion of the perimeter
is not considered fronting on a public way or yard [see
Commentary Figure 506.3.1(1)].
This section requires that an open space that is not
a public way be on the same lot or dedicated for public
use, and it must have access from a street or an
approved fire lane in order to contribute to the frontage
increase.
The requirement that the open space be on the
same lot is so that the owner or the jurisdiction can
control the space that is assumed to be open for purposes
of the area increase. One cannot encumber a
neighbor’s property with a requirement that the space
will always remain unoccupied.
Any part of the perimeter that is not accessible to the
fire department by means of a street or fire lane cannot
be considered open for the purposes of this section.
For instance, if the back side of a building on a narrow
lot cannot be reached by means of a fire lane on one
side of the building (and there is no alley or street at
the back), that portion of the perimeter is not considered
open for purposes of frontage increase, even if
there is actual open space exceeding 20 feet (6096
mm) in width. See Commentary Figure 506.3.1(2) as
an illustration of this limitation.
This section does not require that a fire lane or
street extend immediately adjacent to every portion of
the perimeter that is considered open for purposes of
the increase. Rather, access by a fire lane must be
provided up to the open side such that fire department
personnel can approach the side and pull hoses
across the open area to fight a fire, and no corner of
the building will impede the use of hoses and equipment
on that side of the building. The following examples
demonstrate this point.
Example 1: In Commentary Figure 506.3.1(2), the
south and east side of the building can be considered
open perimeter (frontage). The north side of the
building cannot be considered open perimeter for
purposes of the increase, since it is not accessible
from the street or a fire lane. Even though the 20-footwide
yard can be included in open frontage because it
does not provide a fire lane to the rear of the building,
the 100-foot yard cannot be included.
Example 2: In Commentary Figure 506.3.1(3), all
sides of the building are considered open perimeter
(frontage) for purposes of the increase. Access up to
each side of the building is provided by means of a fire
lane or street.
Section 503 of the International Fire Code® (IFC®)
specifies that access roads extend to within 150 feet
(45 720 mm) of all portions of the exterior walls of a
building. However, there are exceptions that would
permit the omission of such roads under certain
circumstances. One such exception is for buildings
equipped throughout with an automatic sprinkler
system where the fire code official is permitted to
extend the 150-foot (45 720 mm) limit.
The IFC also stipulates that the access roads must
be at least 20 feet (6096 mm) in unobstructed width,
although it also gives the building official authority to
require greater widths if necessary for effective firefighting
operations. The type of surface necessary for
the approved fire lane is determined by the local
building official with input from the fire department, but
the road must be capable of supporting the imposed
loads of fire apparatus and be surfaced so as to
provide all-weather driving capabilities.
There is no requirement in the code that buildings have
at least 25 percent of their perimeter on a public way or
open space. However, in order to qualify for an area
increase, a building must have more than 25 percent of
its perimeter on a public way or open space having a
minimum width of at least 20 feet (6096 mm) (see Section
506.3.2). When the calculations are done, the maximum
percent increase for a fully open perimeter (full
frontage—the entire perimeter fronts on a public way or
open space) is 75 percent. Width is measured at right
angles to the perimeter walls, as set forth in Section
506.3.2, but open frontage is not the same as fire separation
distance. Fire separation distance, as defined in
Section 202, is measured to the centerline of public
ways or to an imaginary line between buildings on the
same lot. Open space can include the total width of the
public way as well as the total open space between
buildings on the same lot. “Public way” is a defined term.
If a structure is divided into two or more buildings by
fire walls complying with Section 706, the area modifications
allowed by Section 506 must be determined
based on each separate building within the structure.
This especially comes into play in determining
increases allowable based on frontage. The fire wall is
essentially the perimeter wall for that side of the building
and must be included in the total perimeter in calculating
the percentage of perimeter on a public way
or open space. Since there is another building on the
other side of the fire wall, this portion of the perimeter
is not considered fronting on a public way or yard [see
Commentary Figure 506.3.1(1)].
This section requires that an open space that is not
a public way be on the same lot or dedicated for public
use, and it must have access from a street or an
approved fire lane in order to contribute to the frontage
increase.
The requirement that the open space be on the
same lot is so that the owner or the jurisdiction can
control the space that is assumed to be open for purposes
of the area increase. One cannot encumber a
neighbor’s property with a requirement that the space
will always remain unoccupied.
Any part of the perimeter that is not accessible to the
fire department by means of a street or fire lane cannot
be considered open for the purposes of this section.
For instance, if the back side of a building on a narrow
lot cannot be reached by means of a fire lane on one
side of the building (and there is no alley or street at
the back), that portion of the perimeter is not considered
open for purposes of frontage increase, even if
there is actual open space exceeding 20 feet (6096
mm) in width. See Commentary Figure 506.3.1(2) as
an illustration of this limitation.
This section does not require that a fire lane or
street extend immediately adjacent to every portion of
the perimeter that is considered open for purposes of
the increase. Rather, access by a fire lane must be
provided up to the open side such that fire department
personnel can approach the side and pull hoses
across the open area to fight a fire, and no corner of
the building will impede the use of hoses and equipment
on that side of the building. The following examples
demonstrate this point.
Example 1: In Commentary Figure 506.3.1(2), the
south and east side of the building can be considered
open perimeter (frontage). The north side of the
building cannot be considered open perimeter for
purposes of the increase, since it is not accessible
from the street or a fire lane. Even though the 20-footwide
yard can be included in open frontage because it
does not provide a fire lane to the rear of the building,
the 100-foot yard cannot be included.
Example 2: In Commentary Figure 506.3.1(3), all
sides of the building are considered open perimeter
(frontage) for purposes of the increase. Access up to
each side of the building is provided by means of a fire
lane or street.
Section 503 of the International Fire Code® (IFC®)
specifies that access roads extend to within 150 feet
(45 720 mm) of all portions of the exterior walls of a
building. However, there are exceptions that would
permit the omission of such roads under certain
circumstances. One such exception is for buildings
equipped throughout with an automatic sprinkler
system where the fire code official is permitted to
extend the 150-foot (45 720 mm) limit.
The IFC also stipulates that the access roads must
be at least 20 feet (6096 mm) in unobstructed width,
although it also gives the building official authority to
require greater widths if necessary for effective firefighting
operations. The type of surface necessary for
the approved fire lane is determined by the local
building official with input from the fire department, but
the road must be capable of supporting the imposed
loads of fire apparatus and be surfaced so as to
provide all-weather driving capabilities.
Yankee Chronicler
REGISTERED
My preferred approach when there is ANY question is to sit down with the fire marshal and the fire chief to review with them whether or not they considered the open space to be suitable for conducting fire fighting operations. That is, after all, the basis on which the code allows the building area to be increased.
As an example, several years ago I looked at a project (which never went beyond the planning stages) where the rear of a building faced an on ramp of an Interstate highway. That's clearly a public road and a public right-of-way. On paper, it looked like a slam dunk. But when I consulted the fire department, their response was "There's no way we're closing down a major Interstate highway ramp to fight a fire in that building. Not good enough."
As an example, several years ago I looked at a project (which never went beyond the planning stages) where the rear of a building faced an on ramp of an Interstate highway. That's clearly a public road and a public right-of-way. On paper, it looked like a slam dunk. But when I consulted the fire department, their response was "There's no way we're closing down a major Interstate highway ramp to fight a fire in that building. Not good enough."