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Occupancy Load / Egress / Stairs with a roof deck.

B

beachfront71

Member
Joined
Apr 9, 2016
Messages
4
Location
Newport Beach, CA
Hello and thank you from California.

I wanted to get some input with regards to accessing my roof deck.

We have a 2 story house - the 2nd floor has a 6' deep x 16' long reinforced balcony that originally had a spiral to the roof. The roof deck is 50x12 but could be made smaller with new railing if needed.

When we remodeled I removed the spiral and am ready to explore spiral alternatives to getting up to the roof and pass code. I despise spirals for what its worth..

My goal is to use the smallest stair width possible.

I have seen this:
R311.7.1 Width.

Stairways shall not be less than 36 inches (914 mm) in clear width at all points above the permitted handrail height and below the required headroom height. Handrails shall not project more than 4.5 inches (114 mm) on either side of the stairway and the minimum clear width of the stairway at and below the handrail height, including treads and landings, shall not be less than 311/2 inches (787 mm) where a handrail is installed on one side and 27 inches (698 mm) where handrails are provided on both sides.

and this:

Private stairways serving an occupant load of less than 10 may be 30 inches wide

Talked to the city and got the standard "minimum is 36" wide but I am under the impression there may be alternatives.

Yes it is a big deck but typically it would host between 4-6 people.

I was trying to understand Occupancy load but it seems most have to do with business and not residential.

Any input would be appreciated with regards to some outside the box thinking that obviously would pass code / or justify a private meeting with the Building department.

I am in Southern California/Orange County on the beach if it matters.

it looks like I could get a double windeer / u shaped staircase in the area which seems to be ideal..
 
Thanks, we have owned the house since 2009 .. I have my arch coming by Monday but thought I would get some other opinions as well.

The spiral that was there was a 60" one so it took up basically 5x5 feet.

I drew out a winding staircase and if I can get the stair width to 30" I could fit it in the same spot as the spiral.

Something like this staircase here (i think I am too new for attachment uploads..):

http://www.stairplan.com/NS3W64N.pdf
 
Might get down to if the city considers it a means of egress??

See what other replies come in
 
R311.7.5.2.1 Winder treads.

Winder treads shall have a minimum tread depth of 10 inches (254 mm) measured between the vertical planes of the foremost projection of adjacent treads at the intersections with the walkline. Winder treads shall have a minimum tread depth of 6 inches (152 mm) at any point within the clear width of the stair. Within any flight of stairs, the largest winder tread depth at the walkline shall not exceed the smallest winder tread by more than 3/8 inch (9.5 mm). Consistently shaped winders at the walkline shall be allowed within the same flight of stairs as rectangular treads and do not have to be within 3/8 inch (9.5 mm) of the rectangular tread depth.

R311.7 Stairways.

R311.7.1 Width.

Stairways shall not be less than 36 inches (914 mm) in clear width at all points above the permitted handrail height and below the required headroom height. Handrails shall not project more than 4.5 inches (114 mm) on either side of the stairway and the minimum clear width of the stairway at and below the handrail height, including treads and landings, shall not be less than 311/2 inches (787 mm) where a handrail is installed on one side and 27 inches (698 mm) where handrails are provided on both sides.

Exception: The width of spiral stairways shall be in accordance with Section R311.7.9.1.
 
Thanks and Yes, I was familiar w/ the winding stair code requirement, I just picked an image on google to show.

Regarding this part:

"and 27 inches (698 mm) where handrails are provided on both sides."

Does that mean as long as your handrail meets code and no obstructions above the handrail, you can have 27"wide stair treads?
 
R311.7.5.2.1 Winder treads.Winder treads shall have a minimum tread depth of 10 inches (254 mm) measured between the vertical planes of the foremost projection of adjacent treads at the intersections with the walkline. Winder treads shall have a minimum tread depth of 6 inches (152 mm) at any point within the clear width of the stair. Within any flight of stairs, the largest winder tread depth at the walkline shall not exceed the smallest winder tread by more than 3/8 inch (9.5 mm). Consistently shaped winders at the walkline shall be allowed within the same flight of stairs as rectangular treads and do not have to be within 3/8 inch (9.5 mm) of the rectangular tread depth.

R311.7 Stairways.

R311.7.1 Width.

Stairways shall not be less than 36 inches (914 mm) in clear width at all points above the permitted handrail height and below the required headroom height. Handrails shall not project more than 4.5 inches (114 mm) on either side of the stairway and the minimum clear width of the stairway at and below the handrail height, including treads and landings, shall not be less than 311/2 inches (787 mm) where a handrail is installed on one side and 27 inches (698 mm) where handrails are provided on both sides.

Exception: The width of spiral stairways shall be in accordance with Section R311.7.9.1.
Click to expand...
Does IRC apply to patios/ roof balconies?

And access from a balcony to roof top patio in my own house
 
I have also read... (somewhere) ... that Winders might not be a means of egress.

This roof deck will have no other enter/exit point than this stairway.

When you leave the roof deck, you will:

A .Travel down to a kitchen balcony --- At this balcony you can either:

1. Enter house via the kitchen or

2. Take another set of exterior stairs to a first floor deck --- at this first floor deck you can

1. Enter house via downstairs living room or

2. Take another set of stair (6 total) to the back yard ground area

I am trying to be detailed so your answers are detailed as well.

My original ? revolved around how you calculate occupancy load for a residential roof deck as it seems the OC can play a factor in egress (which to me means a safe way to enter or exit an area.)

Thanks again.
 
The key phrase in the stair paragraph is "...not be less than 36 inches (914 mm) in clear width at all points above the permitted handrail height and below the required headroom height..." The 36" is measured ABOVE the handrails.

Lacking a local amendment, winders are not restricted as a part of the means of egress in a single family using the Residential Code.

Spirals and alternating tread devices ARE restricted and could not be a component of the MOE.
 
I have also read... (somewhere) ... that Winders might not be a means of egress.This roof deck will have no other enter/exit point than this stairway.

When you leave the roof deck, you will:

A .Travel down to a kitchen balcony --- At this balcony you can either:

1. Enter house via the kitchen or

2. Take another set of exterior stairs to a first floor deck --- at this first floor deck you can

1. Enter house via downstairs living room or

2. Take another set of stair (6 total) to the back yard ground area

I am trying to be detailed so your answers are detailed as well.

My original ? revolved around how you calculate occupancy load for a residential roof deck as it seems the OC can play a factor in egress (which to me means a safe way to enter or exit an area.)

Thanks again.
Click to expand...
Occupant load should not be a factor at a house.

The factor would be either 5,7, or 15 if it did apply
 
The key phrase in the stair paragraph is "...not be less than 36 inches (914 mm) in clear width at all points above the permitted handrail height and below the required headroom height..." The 36" is measured ABOVE the handrails.Lacking a local amendment, winders are not restricted as a part of the means of egress in a single family using the Residential Code.

Spirals and alternating tread devices ARE restricted and could not be a component of the MOE.
Click to expand...
Does IRC apply to patios/ roof top balcony at a resident
 
cda, As long as the home fits within the scope of the Residential Code, the IRC would apply to a rooftop deck.

I believe a 'balcony' is generally considered a cantilevered floor extension on the exterior of a dwelling, and most folks think of grade level when talking about a 'patio', but these would be regulated within the scope of the IRC as well IMHO..
 
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