How to address 1-hour fire-rated stairway within 5′ of property line in San Diego?

[samersalman]

I got a plan-check comment from San Diego DSD saying:

“The south side of the stairway is less than 5 ft. from the property line so it should be 1-hour fire rated. The columns of the stairway that are within 5 ft. from the property line shall be 1-hour fire rated. Provide the 1-hour rated stairway detail.”

What’s the correct way to address and draw this?
Do I need to show a UL-listed wall assembly (like UL U415) along the stair side facing the property line and how to do this?
Also, how do I show the underside of the stair for fire protection in the drawing?

This is for a residential project in San Diego, CA under CRC R302.1(1).

 

[TheCommish]

What is your role in the project? if you are the registered design professional you should consult with a drywall manufacturer listed designs and use them to provide the rated assembly that meets the 1 hour requirements including the underside of the stairs

 

[Yikes]

Welcome to the forum.
Your plan checker should,d be providing you specific code citations to aid you in your response.
Look at CRC Table R302.1. It refers you CBC 703.3 for wall construction techniques. In turn, that will refer you to the gypsum association manual and UL tests.
The CBC and CRC are available to view for free at upcodes.com.

I can’t tell from the section you provided where is the property line relative to the stair, nor can I tell if your stair is an interior stair vs. exterior stair. I can’t tell what your stair is made from, and if it’s an exterior stair, you have not proposed any wall finish (stucco, siding, etc.) that helps us provide a more specific solution.

Also, have you checked to see if San Diego will require you to fire sprinkler the house? If they do, then sprinklers may substitute for fire rated construction under certain conditions - - see CRC R302.1.

 

[samersalman]

What is your role in the project? if you are the registered design professional you should consult with a drywall manufacturer listed designs and use them to provide the rated assembly that meets the 1 hour requirements including the underside of the stairs

I’m an AutoCAD drafter. Whenever the city sends us corrections on a project, my task is to fix them and resubmit to the city. The problem is, I don’t know how to make the drawings.

 

[samersalman]

Welcome to the forum.
Your plan checker should,d be providing you specific code citations to aid you in your response.
Look at CRC Table R302.1. It refers you CBC 703.3 for wall construction techniques. In turn, that will refer you to the gypsum association manual and UL tests.
The CBC and CRC are available to view for free at upcodes.com.

I can’t tell from the section you provided where is the property line relative to the stair, nor can I tell if your stair is an interior stair vs. exterior stair. I can’t tell what your stair is made from, and if it’s an exterior stair, you have not proposed any wall finish (stucco, siding, etc.) that helps us provide a more specific solution.

Also, have you checked to see if San Diego will require you to fire sprinkler the house? If they do, then sprinklers may substitute for fire rated construction under certain conditions - - see CRC R302.1.

Thank you for your response. I just don’t know how to get the detail for the fire-resistant stairway. It’s an exterior stair and it’s less than 4'5" away from the property line. I’ll check to find a reference for it.

 

[arwat23]

There is no "correct" way to address code comments. There are ideal ways, but all you need to do is demonstrate that whatever you have drawn meets the requirements of code. I've addressed similar comments with key notes, wall / stair sections, and sheet notes before. IMO, it depends on your firm's standards and what would best demonstrate compliance.

Isn't R302.1 specific to exterior walls? Would that section apply to exterior stairs? Is a stair a "projection" of the exterior wall? Honest questions, because I don't do much residential...

 

[Yikes]

I'll give you one example, but you have many at your disposal. The side wall / guard of the stair needs to be one hour rated. Let's say your stair is made out of wood. Let's say you aesthetically want to have the wall be plaster, like the wall on the right side of this picture:

CBC table 721.1(2), item 15-1.2 has a one hour assembly consisting of 2x4 studs and 3/4" plaster on each side.

 

[TheCommish]

I’m an AutoCAD drafter. Whenever the city sends us corrections on a project, my task is to fix them and resubmit to the city. The problem is, I don’t know how to make the drawings.

I would direct you to the design professional you are drafting for, it is their responsibility to provide the rated assemblies they want to use.

 

[e hilton]

Reconfigure the stairs so there is an additional landing, turn them 90* so they stay more than 5 ft from the PL.

 

[Yankee Chronicler]

I’m an AutoCAD drafter. Whenever the city sends us corrections on a project, my task is to fix them and resubmit to the city. The problem is, I don’t know how to make the drawings.

It's an unenclosed, exterior stair. There's no enclosure wall to make fire-resistant, and that's primarily what section R302.1 addresses. However, it also addresses projections, and I guess an egress stair could be construed as a projection. In that case, I would look at intumescent coatings.

Then I would ask if an unenclosed egress stair within 5 feet of a property line is allowed at all ...

 

[neyox]

Welcome to the forum.
Your plan checker should,d be providing you specific code citations to aid you in your response.
Look at CRC Table R302.1. It refers you CBC 703.3 for wall construction techniques. In turn, that will refer you to the gypsum association manual and UL tests.
The CBC and CRC are available to view for free at upcodes.com.

I can’t tell from the section you provided where is the property line relative to the stair, nor can I tell if your stair is an interior stair vs. exterior stair. I can’t tell what your stair is made from, and if it’s an exterior stair, you have not proposed any wall finish (stucco, siding, etc.) that helps us provide a more specific solution.

Also, have you checked to see if San Diego will require you to fire sprinkler the house? In the middle of my research on local real estate, I came across the term buy houses Windermere, and if sprinklers are required, they may substitute for fire-rated construction under certain conditions, see CRC R302.1.

Provide a 1-hour fire-rated wall along the stair side and columns within 5 feet of the property line. Show the wall in plan and section views, referencing a UL-listed assembly like UL U415. Protect the underside of the stair with 1-hour rated gypsum board or another approved fire-rated assembly, and note this in the section. Label all elements clearly in the drawings.