Accessible means of egress in R-2 TH

[orphe97]

My first time posting here. Appreciate the great discussions and wealth of knowledge shared on this site. I'm learning a lot from this community.

I'm working on a new multifamily development, 32 4-story multi-level units in two buildings (R-2, NFPA 13D). Each unit has its own entry from exterior. Half of them are townhouses and the other half are inter-locked multi-story units (back-to-back units with living space over neighbor’s garage). 2018 IBC with Seattle amendments.

Based on IBC 1107, two type A units are required, no type B unit. 1009.1 and 1009.2 require each of the type A units to have at least one accessible means of egress to ROW. Due to site restriction, we cannot provide an accessible route from the front door to the ROW for one of the two type A units (the accessible route to the unit is thru the garage).

Our initial review shows that out of the 10 components under 1009.2, #10, exterior area for assisted rescue, seems to be the only solution for this unit. Based on the Commentary, #4 exterior exit stair doesn’t apply to the level of discharge.

The problem of this approach is the 45-minute rated entry door. All other entry doors are fiberglass with glazing. We can’t find a door looks like the rest and is 45-minute rated. These are market-rate for-sale units, and the developer doesn’t want to compromise the look/quality.

I’m trying to understand the intent of 1009.2 Accessible Means of Egress and whether an exterior area of assisted rescue is required. In my research, most examples I found relate to public-use buildings. I haven’t seen this requirement applied to a 2,000 sf townhouse unit.

Items #2, 3 & 4 all refer to stairs, but in this case, only #3 applies. 1019.3 exception 2 doesn’t require stair enclosure within individual units, and 1009.3.3 doesn’t require AOR for R-2. If a 36” wide interior stair qualifies as part of the accessible means of egress, why wouldn’t a 48” wide exterior stair also qualify?

Did I miss something?

 

[Joe.B]

I know this isn't your question, but does the 2018 IBC with Seattle amendments allow a 13D system for R-2 buildings? I thought 13D systems are only allowed in R-3? Are these true "townhouses"?

[F] 903.3.1.3 NFPA 13D sprinkler systems. Automatic
sprinkler systems installed in one- and two-family
dwellings; Group R-3; Group R-4, Condition 1;
and townhouses shall be permitted to be installed
throughout in accordance with NFPA 13D as amended
in Chapter 35.
[A] TOWNHOUSE. A single-family dwelling unit
constructed in a group of three or more attached units in which
each unit extends from the foundation to roof and with open
space on at least two sides.

 

[steveray]

So your accessible route meets this exception?

1104.5​

Accessible routes shall coincide with or be located in the same area as a general circulation path. Where the circulation path is interior, the accessible route shall be interior. Where only one accessible route is provided, the accessible route shall not pass through kitchens, storage rooms, restrooms, closets or similar spaces.

Exceptions:

1. 1.Accessible routes from parking garages contained within and serving Type B units are not required to be interior.
2. 2.A single accessible route is permitted to pass through a kitchen or storage room in an Accessible unit, Type A unit or Type B unit.

And if the route is through the garage, why can't the MOE be?

 

[orphe97]

Joe, good questions.
The original permit was submitted with 13R. Fire department comments the project qualifying for 13D.
One building has only TH units, the other building has the back-to-back units, no TH.

 

[orphe97]

Steve,
My understanding is that accessible route can be front door or garage (by car) but egress can't go thru garage. We tried but couldn't to carve out an enclosed passage thru the garage.

 

[Yankee Chronicler]

Joe, good questions.
The original permit was submitted with 13R. Fire department comments the project qualifying for 13D.
One building has only TH units, the other building has the back-to-back units, no TH.

Your original post said (or implied) that both buildings are 4-story. A 4-story building is not a townhouse and can't be designed or built under the IRC.

 

[orphe97]

The project is under IBC. IBC defines townhouse units as "a single-family dwelling unit in a townhouse that extends from foundation to roof, has a yard or ROW on no less than 2 sides, extends at least 50% of each of the two sides".
Regarding to the fire department comment, no reasoning was given and we didn't ask, either.

 

[orphe97]

I should add the project is currently under permit review. We received and responded to the first round of corrections (including type A units and sprinkler) and are reviewing the 2nd round of comments. The original question is from developer/contractor, not AHJ.

 

[Joe.B]

The project is under IBC. IBC defines townhouse units as "a single-family dwelling unit in a townhouse that extends from foundation to roof, has a yard or ROW on no less than 2 sides, extends at least 50% of each of the two sides".
Regarding to the fire department comment, no reasoning was given and we didn't ask, either.

AHJ's make mistakes, more often than we'd like, and us making a mistake does not protect you and your client. Imagine an insurance company found out the wrong sprinkler system was installed, perfect excuse to deny a claim. For you and your clients own protection I would strongly recommend a 13R system.

 

[orphe97]

good point on the insurance. I'll bring it up to the project manager (it's not my project and I'm just helping out).