ARE 4.0 Stair Solution & Questions

[scmc872]

Hello All,

Please let me know if you see any glaring issues with this stair solution. All risers are 7" (12'-3" / 7" = 21 risers. 1'-9" / 7" = 3 risers. Since 7" goes into both perfectly I just used 7" risers as that is the most efficient stair). Of course all treads are 11".

A few questions:

1. Should we show the handrails returning into the wall? I assume since this requirement is not written into the program codes then we don't need to worry about it.

2. This one is trickier. They specify that at least 1 handrail must extend 12" past the bottom and top stair. Generally in real life we leave an extra tread depth at the bottom of a run to account for the space a handrail needs to reach 36" a.f.f. (while following the slope of the stair) before we turn the handrail 90 or 180 degrees. If you don't do this you end up with a handrail that is 36" above the lowest nosing, but must come down vertically to remain at the edge of the landing and be 36" a.f.f. BUT, in NCARB vignette land I would rather go through my solution using the tightest stair possible so that I can hopefully avoid headroom clearance, AoR clearance, Door clearance, and landing width issues when I'm checking my solution. In retrospect this solution has plenty of room for me to leave an extra tread depth on each landing and move back/extend the highest stair run (from 9'11" landing to 2nd floor), but if this isn't required I'd rather not add an extra tread depth to each of my landings.

Thank you!

1st Floor.jpg

2nd Floor.jpg

[carpar]

Hello All,

Please let me know if you see any glaring issues with this stair solution. All risers are 7" (12'-3" / 7" = 21 risers. 1'-9" / 7" = 3 risers. Since 7" goes into both perfectly I just used 7" risers as that is the most efficient stair). Of course all treads are 11".

A few questions:

1. Should we show the handrails returning into the wall? I assume since this requirement is not written into the program codes then we don't need to worry about it.

I think as you've shown it looks fine to me. It's what the NCARB solution is showing.

2. This one is trickier. They specify that at least 1 handrail must extend 12" past the bottom and top stair. Generally in real life we leave an extra tread depth at the bottom of a run to account for the space a handrail needs to reach 36" a.f.f. (while following the slope of the stair) before we turn the handrail 90 or 180 degrees. If you don't do this you end up with a handrail that is 36" above the lowest nosing, but must come down vertically to remain at the edge of the landing and be 36" a.f.f. BUT, in NCARB vignette land I would rather go through my solution using the tightest stair possible so that I can hopefully avoid headroom clearance, AoR clearance, Door clearance, and landing width issues when I'm checking my solution. In retrospect this solution has plenty of room for me to leave an extra tread depth on each landing and move back/extend the highest stair run (from 9'11" landing to 2nd floor), but if this isn't required I'd rather not add an extra tread depth to each of my landings.

I know what you mean, but I think it's whatever the vignette instructions are telling us, 12" extension.

Thank you!

1st Floor.jpg

2nd Floor.jpg

[concepts]

In the solution above, would there have been a penalty for having a larger landing than necessary, say, increased as shown in my attachment ? It is unclear to me if "Stairways shall not reduce in width in the direction of egress travel" means that max landing widths apply.

Capture.PNG

[Coach]

In the solution above, would there have been a penalty for having a larger landing than necessary, say, increased as shown in my attachment ?

No. Just be reasonable.

It is unclear to me if "Stairways shall not reduce in width in the direction of egress travel" means that max landing widths apply.

Landing size has no impact on required stair width.

[concepts]

Thanks, Coach!