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Building Area Frontage Increase

RANDOM

RANDOM

Member
Joined
Apr 11, 2016
Messages
49
Location
San Gabriel Valley
Hi guys,

I am designing a Type IIB building with only 1 story above ground level. The building is made of tilt up panels with steel structural columns.

I was wondering if I can increase the area due to frontage. This particular building would have an open perimeter with at least 26' of width.

I would like to know if having transformers all along the perimeter would "block" the area increase. These transformers are 7'x8'x7' and are separated from the concrete panel wall by 6'-0".

I would really appreciate your feedback.
 
The open space required for the area increase due to frontage is to facilitate fire fighting operations. I would not count the yards that have transformers in the open space as the transformers would impede fire fighters IMHO.
 
The open perimeter is to allow access for fire apparatus..... if you are maintaining the requirements for fire department access in IFC and location of fire department access roads as may be required by appendix D especially

D105.3 Proximity to building.
At least one of the required access routes meeting this condition shall be located within a minimum of 15 feet (4572 mm) and a maximum of 30 feet (9144 mm) from the building, and shall be positioned parallel to one entire side of the building. The side of the building on which the aerial fire apparatus access road is positioned shall be approved by the fire code official.

D105.4 Obstructions.
Overhead utility and power lines shall not be located over the aerial fire apparatus access road or between the aerial fire apparatus road and the building. Other obstructions shall be permitted to be placed with the approval of the fire code official.
 
Builder Bob said:
The open perimeter is to allow access for fire apparatus..... if you are maintaining the requirements for fire department access in IFC and location of fire department access roads as may be required by appendix D especially

D105.3 Proximity to building.
At least one of the required access routes meeting this condition shall be located within a minimum of 15 feet (4572 mm) and a maximum of 30 feet (9144 mm) from the building, and shall be positioned parallel to one entire side of the building. The side of the building on which the aerial fire apparatus access road is positioned shall be approved by the fire code official.

D105.4 Obstructions.
Overhead utility and power lines shall not be located over the aerial fire apparatus access road or between the aerial fire apparatus road and the building. Other obstructions shall be permitted to be placed with the approval of the fire code official.
Click to expand...

B Bob, that is for buildings more than 30' above grade plane. While that is a possibility for a one story building, it is not really applicable to this query.
 
JBI, I know but sometimes to make life simpler for designers, you tend to stick to these rules even when the buildings don't quite meet the height limitations.

The 15 to 30 foot rule is easier to explain and a heck of a lot easier to make a common practice when the AHJ is consistant on the requirements.

I used to talk to designers and explain although it wasn't a requirement, it would be a good idea to maintain these requirements as that was what our department was used to and we had started using quints.... (combination aerial and pumper for all calls.)
 
Not that I agree or disagree . . .

The provisions of this appendix are not part of this code and are provided only as a resource for local governments in consideration of the adoption of local fire prevention regulations.


 
Area increase (frontage increase) is in Chapter 5 of building code (IBC) (506.2 Frontage Increase).

What we can and can’t use frontage area open space for is very loosely defined in IBC. We know it is an open space which I understand it to be an unobstructed area from the ground to the sky located on lot or a dedicated easement.

We cannot place storage like a big store have outside but we can park, landscape, install fire hydrants and lights. What I see as a key difference between what is permitted and what is not is storage is not permitted in public way, ROW or a street but transformers, cars, lights, etc are permitted.

If I was reviewing the plans I would not like it but I would not comment if one transformer. You posted "transformers all along the perimeter would "block" the area increase". I would comment and say you do not meet the intent of open space so no area increase.
 
Commentary IBC 506.2

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 ofSection 506.2. 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 Figure 506.2.2(1) 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.

For clarification of the second paragraph, here is the code section from the International Fire Code pertaining to Fire Department Access

503.1.1 Buildings and facilities.
Approved fire apparatus access roads shall be provided for every facility, building or portion of a building hereafter constructed or moved into or within the jurisdiction. The fire apparatus access road shall comply with the requirements of this section and shall extend to within 150 feet (45 720 mm) of all portions of the facility and all portions of the exterior walls of the first story of the building as measured by an approved route around the exterior of the building or facility
 
Open space for frontage increase and fire department access requirements are two different requirements. They can be combined and serve the same purpose but not required
Example would be a drainage swale and landscaped area would provide the open space but not meet the fire department access requirements.
I would need more info since the OP stated "I would like to know if having transformers all along the perimeter " is not clear about how many transformers and how many sides he is referring to
 
I'm picturing the Fire Service shooting hose streams over (potentially) live transformers. It's not a pretty picture...

The area increase for frontage is based on the Fire Service being able to attack from the exterior with, among other things, hose streams.
 
JBI said:
I'm picturing the Fire Service shooting hose streams over (potentially) live transformers. It's not a pretty picture...

The area increase for frontage is based on the Fire Service being able to attack from the exterior with, among other things, hose streams.
Click to expand...

Don't they get rained on all the time? Pretty sure they have a decent NEMA rating...
 
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Additional guidance from the 2015 IBC Handbook to help you with your own interpretation.

"YARD. Used throughout the code to describe an open space at the exterior of a building, a yard must be unobstructed from the ground to the sky and located on the same lot on which the building is situated. A court, which is bounded on three or more sides by the exterior walls of the building, is not considered a yard. Both a yard and a court are expected to provide adequate openness and natural ventilation so that the accumulation of smoke and toxic gases will not occur.

It is not intended that exterior areas devoted to parking, landscaping, or signage be prohibited to qualify as a yard, provided access to and from the building is available and maintained for both the occupants and fire department personnel. It is also important to recognize that the code provisions sometimes require a yard and at other times an open space, as well as references to fire separation distance. Although the differences may appear to be subtle, each term is
applied somewhat differently.

Open space and public ways—what can and cannot be used. In addition to allowances for public ways, the IBC uses the term open space where related to frontage increases in the determination of allowable floor areas. Although the term open space is not specifically defined in the IBC, the definition of a yard is an open space unobstructed from the ground to the sky that is located on the lot on which the building is situated. It is logical that this definition is consistent with the intended description of open space. This definition seems to preclude the storage of pallets, lumber, manufactured goods, home improvement materials, or any other objects that similarly obstruct the open space. However, it would seem reasonable to permit automobile parking, low-profile landscaping, fire hydrants, light standards, and similar features to occupy the open space. These types of obstructions can be found within the public way, so their allowance within the open space provides for consistency. Because a yard must be unobstructed from the ground to the sky, open space widths should be measured from the edge of roof overhangs or other projections . . . "
 
Builder Bob said:
I assume that all conductors are underground without any overhead wires?
Click to expand...

Nope. They go above the transformers into the panel because they feed the second level as well. Actually the conductors are encased in a duct. The whole transformer + conductors thing is not even 12' tall.
 
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