Appeal 33407

705.8.1

Original appeal: For a wall that is 10 to less than 15 feet from a property line, in a fire sprinklered building the allowable area of unprotected openings is 45%

Reconsideration: The maximum area of unprotected openings permitted in an exterior wall in any story of a building shall not exceed the percentages specified in table 705.8 based on the fire separation distance of each individual story. Per Table 705.8 an exterior wall that is 10 to less than 15 feet from a property line, in a fire sprinklered building the allowable area of unprotected openings is 45%

Original appeal: To verify the term “Exterior Wall” in the description of this table to refer to the wall that separates the inside from the outside vs referring to the open space that is below a wall on the floor above the open space.

Reconsideration:
To consider the entire façade as the exterior wall vs each individual story.

Original appeal: The proposal is to consider the wall facing the property line on the first floor, which is the wall with a door in it accessing the outdoor space, as the wall with the unprotected openings and not consider the open space at the edge of the wall above it as a wall.

Reconsideration:
The exterior façade is 1,714 square feet and the allowable unprotected openings is 45% of that number which is 770 square feet. The amount of unprotected openings in this façade is 531 square feet which is 31% of the façade. The proposal is to consider the whole façade having fewer than 45% unprotected openings instead of each story. Also on the first floor the wall separating the interior from the exterior space is not being considered the exterior wall to be regulated by fire code, then it is not required to be 2-hour fire rated like the rest of the exterior walls. We are proposing to continue that 2-hour fire rating on this wall.

Original appeal: The area we are discussing is an open outdoor area on the first floor which is to be used by the tenants of the apartment building as common outdoor area. This area has walls on three sides and no wall on the 4th side, which is also open to an uncovered outdoor area, the area is also covered by a portion of the 2nd floor. The reason for the alternate is because the title of this section is describing the “area of exterior wall openings”. I am proposing that the exterior wall is the wall that is separating the inside from the outside, even if the outside is a covered outdoor space. I am being told by my plans examiner that the exterior wall is the open area/plane which is at the edge of the façade on the 2nd floor, which actually isn’t a wall at all but an open space.

One reason I would propose the wall with the door in it is to be considered the exterior wall is this, if that wall is not the exterior wall then what is it called? An interior wall? That wall is currently a 2-hour fire rated wall to comply with the regulations of type 3B construction requiring exterior walls to have that fire rating. If that wall is considered an interior wall then am I to not fire rate that wall? If that wall with the door in it is interior then do I not insulate it as an exterior wall?

A reason the open space should not be considered an exterior wall is it is really hard to insulate that wall to meet energy codes.

Another reason to consider the wall with the door in it as the exterior wall is the city of Portland has a history of accepting that type of wall as the exterior wall in many other projects in the examples of covered balconies and covered outdoor stairwells. For example on a balcony that is covered by another balcony or roof, the guardrail is not considered the exterior wall, the wall with the door to the balcony is. In examples of covered exterior staircases that access multiple apartments the city has not considered the area below the edge of the roof as the exterior wall but considered the walls with doors in them leading into apartments as the exterior wall. I have received approved permits from my current plans examiner Steven Freeh with these designs and also have received permits from plans examiners Guy Altman, Kent Hegsted and Robert Keal with this understanding on what an exterior wall is. I propose you continue to consider the walls as exterior walls and not the air space under a roof or second floor as an exterior wall.

Another reason to consider the wall with the door in it as an exterior wall is to follow the reason for this code in the first place. It seems the whole point of table 705.8 is to protect a structure from fire spreading from one building to the next by putting a fire rated wall in it’s path, with an acceptable amount of openings. If that covered open area on the first floor has at least 1-hour walls and ceiling I don’t see how that doesn’t meet this code, a fire approaching this space will be faced with fire rated assemblies. The only unprotected opening on the first floor in this area is the door in the wall to the outdoor space which is 25 feet from the property line. That is the only unprotected opening and that would be how a fire gets into a building, not through the fire rated walls or ceiling. And in this situation that door is meeting the unprotected opening code with plenty of room to spare.

Another reason to consider is I am being told that the open space is considered an exterior wall because of the second floor above it ends at that spot. When I calculate the unprotected openings in a wall I have been told over the years that we count the wall to opening ratio elevation view per floor and not per elevation of the whole building. For example on just the second floor I take the wall area of that second floor and divide out just the windows on that second floor to get my percentage of unprotected openings on the second floor. I propose if that is the way we calculate the walls then the second floor wall has nothing to do with the first floor wall in this table, they are calculated separately. And if they are calculated separately it makes no sense to consider the open space under another story as a wall but would be better to consider the actual wall facing the property line as a wall. If you do want to consider the whole elevation as one exterior wall, and not calculate it floor at a time, then my whole wall is 1,714 square feet and I have 462 square feet of unprotected openings (including windows and this open area we are discussing) and the total unprotected openings add up to 27% and I am allowed 45%, see attached elevation. So I propose it meets this code either way you add it up but you need to pick one or the other.

Here is another reason, the definition of exterior wall under chapter 2 is “A wall, bearing or nonbearing, that is used as an enclosing wall for a building, other than a fire wall, and that has a slope of 60 degrees or greater with the horizontal plane”. That seems to explain the wall with the door in it vs the open space I am being told I need to count as a wall. I propose that we consider the wall with the door in it as the exterior wall due to the definition of exterior wall.

Reconsideration:
The main reason for this alternative is the planning bureau requires a common outdoor area for the residents of this apartment building and this large opening provides the required natural air and ventilation required for the enjoyment of this covered outdoor space. If we are counting the opening between the covered and the uncovered exterior space an unprotected opening then the first floor has 62% unprotected openings. That large open space does have a 2-hour fire rated wall separating it from the interior space. The 2nd floor has 17% unprotected openings and the 3rd floor has 12%. The 2nd and 3rd floors are way below the maximum of 45% and this is why I feel the building as a whole is meeting this code with the façade as a whole having only 31% unprotected openings.

Consider that first floor does have a 333 square foot unprotected opening which is not a window or a door but an opening to an exterior patio. The walls between that patio and the interior of the building are 2-hour fire rated. That is a fire wall that is an additional layer of protection to the codes listed in table 705.8. Also this patio has a 1-hour fire rated ceiling. All of this provides additional protection that is not required inside an unprotected opening and this is the additional protection that makes me feel this design is meeting the code.

Table 716.1 (2) 2-hour Fire Rating required between stairwells

A 2-hour fire rated enclosure at interior exit stairways

Using a 2-hour shaft assembly under a staircase

Original appeal:
I will be using a 2-hour shaft assembly GA file #WP 7125 as the 2-hour assembly under a wood framed staircase to separate one stairway from another. You can see my stair section and details on attached sheet 8.1 and the assembly at detail K/2.0

Reconsideration:
Using the same 2-hour shaft assembly in the original appeal and adding the steel “studs” to the sides of the wood stringers to complete the 2-hour fire rating as specifically stated in the fire resistance design manual.

Original appeal:
First reason is there is no fire rated assembly for staircases. Because of this the Portland appeals board has approved appeals of using shaft enclosure assemblies under staircases to meet required fire separations. I chose this assembly because it was a one-sided assembly as it’s easier to apply the entire assembly to just the underside of the staircase and not to both sides. This assembly was tested when applied to a 1 5/8” steel stud and it appears that the layers of gypsum and steel straps has little to do with the stud it’s attached to and appears that a wood stud, or stringer in this case, would perform the same way. This assembly also uses screws and not nails to hold it together and I feel would work best in this location.

Reconsideration:
In the original appeal there was concern for using wood stringers to attach the gyp bd to when the listed assembly was referring to using steel studs. So to completely comply to the listing I am adding the steel studs to the assembly.

Section 1028.2 Exception 1.1 Exit Discharge

Original comment:
Exits shall discharge directly to the exterior of the building: Not more than 50% of the required capacity of interior exit stairways is permitted to egress through areas on the level of discharge provided that all of the following conditions are met. Exception 1.1 Discharge of interior exit stairways shall be provided with a free and unobstructed path of travel to an exterior exit door and such exit is readily visible and identifiable from the point of termination of the enclosure.

Original comment:
That the exit is identifiable by signage.

Reconsideration:
To add an exit passageway between the stair enclosure and the exterior exit door.

Original comment:
The proposal is to add an illuminated exit sign to be visible from the exit discharge, the door from the stairwell to the lobby.

Reconsideration: To still add the illuminated exit sign to be visible from the exit stair enclosure but to also consider the area between the exit stair enclosure and the exterior exit door an exit passageway by making the walls and ceiling at the corridor 2-hour fire rated construction. The doors in the exit passageway will be 90-minute rated.

Original comment:
Portland has been struggling with excessive crime which has led to at least this property owner to want the residents of this apartment building to feel safer within the entrance lobby by having less direct view from the front door at the sidewalk to the interior of the common space. This has resulted to the common hallway on the first floor to have a jog in it to obstruct views from the outside to the inside. This result has the opposite problem faced with this code of occupants not having direct view from the exit discharge to the exterior exit door. The design is not completely missing this section of the code, the requirement includes having a “free and unobstructed path of travel to an exterior exit door” which is does. The hallway is unobstructed and is 8’-10” wide right at the exit from the exit stairway and then is 6’-6” wide the rest of the way to the exterior exit door. 7 feet out of the exit stairway the exterior exit door is visible, the total distance from the exit stairway to the exterior exit door is 35 feet. It’s just the “readily visible from the point of termination of the enclosure” part of this exception that this design is not meeting. Due to that I am proposing adding an illuminated exit sign that is clearly visible from the exit stairway that points toward the exterior exit door, that would allow occupants to clearly identify which direction the exterior exit door is.

Reconsideration:
This corridor design is still affected by the rise in crime in Portland and the property owner wanting the tenants living in this building to feel safer within the entrance lobby by having a less direct view from the exterior to the center of the building. I feel by adding a 2-hour exit passageway this gives the occupants the same level of protection that they had while in the exit stair enclosure. This same level of protection continues to the exterior exit door.