Unlimited Area Building with Retaining Wall in the 60' Open Space

[mstehlin]

IBC 2009 507.1 I have an fully suppressed, unlimited area building with 60' open area on all sides. On one long side of the building, there is a 8-12' tall retaining wall about 30' away from the building. The unlimited area building is on the low side of the wall, so it creates a restricted outdoor "channel" that could constrict fire-fighting operations, but it meets all the other requirements, has a paved 20' fire lane etc.

I looked at the commentary, and it says the open space can include a parking lot or accessory features such as tanks, generators and dumpster enclosures. And I know often this 60' will include wooded areas or hills, but this seems extreme.

The local fire department is OK with it. I am leaning towards approving this. Would you?

 

[mtlogcabin]

First Welcome to the Board since this is your 1st post

is surrounded and adjoined by public ways or yards not less than 60 feet (18 288 mm) in width.



Yes i would approve it since it meets the definiton of yard

YARD. An open space, other than a court , unobstructed from the ground to the sky, except where specifically provided by this code, on the lot on which a building is situated.

 

[north star]

~ ~ ~ ~



mstehlin,

1st, ...welcome to The Building Codes Forum!

2nd, ...what is the intent of the 60 ft. open area?......Is it to allow

for MOE from the building, ...is it to allow for fire fighting access

to the building, ...is it to ensure that adjacent properties aren't

affected by any type of fire event, ...all of the above, ...other?

I will respectfully disagree with **mtlogcabin** and say that

you do not have a clear, open 60 ft. space on the side with the

retaining wall......IMO, I believe that the 8'-12' wall is a barrier

...obstruction if you will, by the difference in grades......Section

507.5 [ in the `09 IBC ] allows the open space requirement to

be reduced to 40 ft. with more requirements on the reduced

open space side of the building.

That said, ...if your fire dept. will approve the design, then I

would also approve the design, but it would be based on their

approval and not the letter of the code sections listed.

The fire dept. will be the ones on site with "skin in the game"

and not me!

Does that make sense?

~ ~ ~ ~

 

[fatboy]

FD is good with it,I would approve. The other intent of that section is being met, separation from other structures.

Oh, and welcome to the forum...... :cowboy

 

[mstehlin]

Thanks guys. That helps.

I have intentions of posting more here.

 

[steveray]

I agree with the others that the 60' just has to be open to the sky.....it never says anything about driving a firetruck or anything like that.....it could be a cliff to the ocean. I believe it is more for clearance to other buildings than serrious FD access....

 

[mn joe]

I disagree that this situation meets the intent of the 60 feet open space. in looking at the 2006 IBC Handbook,it specifically addresses this situation. On page 108 of the handbook, addressing frontage increases, the text states "For example,where the space adjacent to the building is heavily forested or steeply sloped, the frontage increase addressed in section 502.6is not permitted. The presence of a lake or similar water feature next to a building would also prohibit an area increase. The evaluation of each individual buildin and its site conditions is necessary to properly apply the code for fire department access."

In addition, 2006 IBC section 507.5 Reduced open space, allows the open space to be reduced to not less than 40 feet under certain conditions, incuding that the wall and its openings facing the reduced space have a minimum 3 hr. rating.

As the building Official I would not defer this decision to the fire department. They are not the code official that is charged with enforcement.

You can check to see if the code that you have adopted (2009 or 2012) is any different.

Joe

 

[Codegeek]

The 2009 IBC Commentary says that the purpose of the 60 feet of open space is two-fold: separation of the buildings from other buildings AND ample space on all sides for fire-fighting operations. The whole purpose of the 60 feet open area is to diminish the spread of potential fire to adjacent buildings/properties. If the FD is good with the site as proposed, I believe it meets the intent of the 60 feet open area requirement.

 

[steveray]

Ask your FD if they are going to drive their 80,000lb truck on the grass around a building......

 

[High Desert]

They still have to meet the fire access requirements of whatever fire code that is adopted. We adopt the IFC and allow those things in the yards as long as they they can still maintain the fire access to the building.

 

[mn joe]

Northstar has it right. The retaining wall is no different than a building wall when you are evaluating open space. This example does not even provide the minimum 40 feet reduced clear space.

That being said; Northstar, why would you approve this just because the "fire department thought it was OK"? Is any one on the fire department a qualified Code Official? Who has jurisdiction? You even say you would not base your decision on the letter of the code.

I have come to expect a more reasoned response, based on the approproate code, from the members of this board. I'm disappointed.

 

[Markmax33]

I agree with CodeGeek and others in favor of allowing it - 2009 IBC Commentary section 507:

"The open space located on the private property

does not need to be dedicated to the public or publicly

owned, but can be the location of parking, landscaping,

roadways and other minor accessory features

(tanks, generators, trash dumpster enclosures) (see

IBC Interpretation No. 20-03). However, the yard

cannot be occupied by any exterior use that is essentially

a continuation of use of the building. For example,

many big box retailers will have an adjoining lawn

and garden merchandise area; or a lumber supply

area that is only partially enclosed by walls, fencing

and roof covering. This type of use would need to be

considered part of the unlimited area building, and the

60 feet (18 288 mm) of open space provided beyond

this area (see IBC Interpretation No. 03-05).

The open areas serve two key roles: separation of

these buildings from other buildings and ample space

on all sides for fire-fighting operations. These buildings

are limited to stories above grade plane because

basements would not be directly accessible for fire

fighting.

Please note that Section 507.5 permits a reduction

in the open space in exchange for increased wall and

opening protection."

I would not ask the fire department if they are okay with it, as they will always give you the most conservative answer of NO. I would ask them in a round about way possibly and ask them, "How much space do you need to fight a fire in a this type of building?" - ensure turn arounds and everything else are squared away as usual.

 

[brudgers]

Northstar has it right. The retaining wall is no different than a building wall when you are evaluating open space.

Dirt doesn't burn. The difference is substantial.