Table 705.8 footnote d.

[Francis Vineyard]

Does this exception include Unprotected, Nonsprinklered (UP, NS) where openings are not permitted?

 

[cda]

Which edition

Are all r's presumed by the code to be sprinkled??

 

[Francis Vineyard]

I think the intent of footnote d. is to permit 25% unprotected and protected respectively as shown in the table; but it seems this line of reasoning would seem to contradict footnote f. where unlimited openings would be permitted for the same condition; UP, NS

 

[mtlogcabin]

Footnote "d" applies to a 3 to 5 foot fire separation distance
Footnote "f" is for over a 5 foot fire separation distance

 

[Francis Vineyard]

Footnote "d" applies to a 3 to 5 foot fire separation distance
Footnote "f" is for over a 5 foot fire separation distance

Is it permitted to have 25% unprotected openings in all three conditions at 3 to 5?

If not then the same reasoning applies to footnote f with unlimited openings?

 

[Francis Vineyard]

 

[cda]

Code anticipates R's to be sprinkled??

 

[Francis Vineyard]

Code anticipates R's to be sprinkled??

It's optional and required as applicable.

 

[Mark Sigler]

Agree with cda, the footnote only applies to R occupancies and the code requires all R occupancies to be sprinkled so the UP (unprotected), NS (unsprinkled) would not apply.

 

[Francis Vineyard]

To restate the question; is it permitted to have 25% opening where it is not permitted at 3 to less than 5 ft.?

 

[mtlogcabin]

Footnote "d" allows only R-3 occupancies to have a total combined protected and unprotected openings of 25% between 3 & 5 foot fire separation distances

Footnote "f" allows all protected and unprotected opening in R-3 occupancies to be unlimited in size if the fire separation distance is greater than 5 feet

f. The area of unprotected and protected openings shall not be limited for Group R-3 occupancies, with a fire separation distance of 5 feet or greater.

 

[Francis Vineyard]

Footnote "d" allows only R-3 occupancies to have a total combined protected and unprotected openings of 25% between 3 & 5 foot fire separation distances

Footnote "f" allows all protected and unprotected opening in R-3 occupancies to be unlimited in size if the fire separation distance is greater than 5 feet

f. The area of unprotected and protected openings shall not be limited for Group R-3 occupancies, with a fire separation distance of 5 feet or greater.

Thanks for understanding my question.

As I understand your interpretation it is allowed to have 25% of unprotected openings where it would not be permitted for other occupancies.

And this interpretation for R-3 aligns with openings not limited greater than 5 ft.

Thanks again for sticking with me on this question.

 

[Francis Vineyard]

I suppose if they wanted to exclude the UP, NS conditions they would have put the footnote designation in the (center) 2nd or 3rd column as done with h and i.

 

[my250r11]

And this interpretation for R-3 aligns with openings not limited greater than 5 ft.

That is what i gathered from reading the commentary from the 2015.

 

[Francis Vineyard]

Mike, can you give us the paragraph? Though I read the commentary quickly I didn't find a reference to the footnote d.

 

[my250r11]

705.8 Openings. Openings in exterior walls shall comply
with Sections 705.8.1 through 705.8.6.
The requirements of this section limit the allowable
area of openings in exterior walls and are applicable
to buildings with or without walls with FSDs less than
30 feet (9144 mm). The limitations on openings in
exterior walls is a function of FSD (see definition this
chapter) and the degree of protection provided for the
opening. The degree of protection of the openings is
either unprotected in a nonsprinklered building (UP,
NS), unprotected in a sprinklered building (UP, S) or
protected openings (P). Protected openings are
openings with fire doors, fire shutters or fire window
assemblies that comply with Sections 716.5 and
716.6. Sprinklered buildings are buildings with an
NFPA 13 sprinkler system. Buildings with only an
NFPA 13 R system shall be considered nonsprinklered
for the purpose of opening limitations in exterior
walls. The percentage of openings allowed is in
Table 705.8, subject to the exceptions in Section
705.8.1.
TABLE 705.8. See page 7-20.
Table 705.8, on page 7-20, provides allowable areas
for exterior wall openings for structures based on the
FSD of the exterior wall and the degree of protection
afforded to the opening, such as fire shutters and
automatic sprinkler systems. The more protection
provided, the larger the area of openings can get.

705.8.1 Exception 2 is for openings in all exterior walls in all
stories where Tables 601 and 602 do not require any
exterior wall (bearing or nonbearing) or primary structural
member to be fire-resistance rated. Therefore,
this exception is only applicable to Type IIB and VB
construction with an FSD of 10 feet (3048 mm) or
greater. This allows unlimited unprotected openings
in Type IIB and VB construction for all exterior walls
facing an FSD of 10 feet (3048 mm) or more.

Then FOOTNOTE F:
f. The area of unprotected and protected openings shall not be limited for Group R-3 occupancies, with a fire separation distance of 5 feet or greater.

It takes some reading around but I gather that the footnote reduces the 10ft or greater to 5ft on the R-3. I believe this to be so it lines up with 601 & 602.