9.5 Exterior Stairs vs Fire Escape

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    • #12645
      John WilsonJohn Wilson
      Participant
      • Department Name: Perth Fire Services

      I’m looking for input/opinions on exterior stairs vs fire escape and how to distinguish between them (or do we even need to).

      When considering 9.5.3.7., is a ‘fire escape’ actually a fire escape or is it an exterior stair? With the conventional steel structures that we all picture when someone says “fire escape”, it’s hard to argue that they are a fire escape and the openings need the closures per the Article. But what about the wood ones?  Where do they fit in the puzzle? Neither “exterior stair” or “fire escape” are defined terms in either OFC or OBC so there’s no help there.

      OBC permits wood fire escapes on buildings of combustible construction with specific minimum dimensions for materials. I’ve got quite a number of 3 storey buildings with wood stairs as the secondary egress. Some of these also have landing/deck areas that are large enough to easily have table & chairs without being in the path of travel. Others are used more as the primary access/egress simply due to where it puts them out at ground level.

      So if it’s not a ‘fire escape’ but considered an ‘exterior exit stair’, what about the separations? Instead of going to 9.5.3.7. do I then go to 9.5.3.3.? These are most (if not all) Type 3 – Ordinary buildings so they’ve got the masonry exterior walls so that’s fine but what about the openings? The entire wall would be considered a fire separation so that would put me to 9.5.2.8. but there’s nothing that gives distance limitations like with a fire escape under 9.5.3.7. If I go that route and consider it a fire escape, the table and chairs off to the side still technically shouldn’t be there.

      I could always try to make an argument under 21(1)(f) instead of (g) but I tend to stick with just what’s in the book because it takes a whole lot less justification and harder to challenge.

      Anyone else as lost as me on this?

    • #12651
      Robert KingRobert King
      Participant

      Jon,

      If you follow the definitions within either building or fire code for “exit”, “means of egress” and “access to exit” you should come to the conclusion that exterior stairs cannot be considered as an “exit stairway” (Exit’s are part of a means of egress which is a continuous path of travel from any point in a building).

      If the fire escape (exterior stairs) is serving as a required exit then sentence 9.5.3.7. (1) applies.

      Even if you wanted to look at it as an exit stairway, then Sentence 9.5.3.3.(1) would require it be protected by a 30 or 45 minute fire resistance rating depending upon building height.

      I’m not sure why you refer to the building as Type 3, in Ontario we have combustible, non-combustible and heavy timber. Sounds to me like you are dealing with a combustible building. You would have to have the owner get a qualified designer to specify the fire resistance rating of the exterior wall assembly to confirm it met the 30 or 45 minute fire resistance rating, and then of course there are the requirements for protection of openings in fire separations. Likely less expensive for the owner to protect window and door openings adjacent the fire escape.

      The building code doesn’t allow fire escapes to be constructed on “new buildings”, however the building code does allow exterior  stairs provided they are not a required exit, or in some cases where the dwelling unit has a second and separate means of egress.

      Hope this helps.

      Rob

       

    • #12652
      George MacrisGeorge Macris
      Participant

      Hi Jon,

      If the exterior stair serves a required exit then these stairs are considered  a “fire escape” and need to apply all the requirements as mentioned in 9.5.3.7.

      If the exterior stairs does not serve a required exit then you don’t apply any of the requirements in 9.5.3.7. That all you have to worry about.

      The requirement for protection of openings on the building wall is to prevent a fire from breaking through the openings and preventing occupants from exiting via the fire escape. If this is not a fire escape because it does not serve a required exit there is no need for protection according to the code because it’s not a required exit, technically it can be blocked off.

      I’m not sure why Rob above is asking you to obtain an engineer’s report for the exterior wall. Why would a wall have a fire resistance rating and furthermore this has nothing to do with the subject matter, it’s not applicable. We don’t even have the right to ask for an engineers report, what reference you are going to use? Also a fire escape is permitted to be installed under 9.5.3.7.;we are not enforcing the OBC on a new building, that’s the Building Department.

      Keep safe,

      GM

    • #12653
      John WilsonJohn Wilson
      Participant
      • Department Name: Perth Fire Services

      Hi Guys,

      Check OBC 3.4.1.4.(1)(d) exterior stairway, and (e) fire escape (conforming to Subsection 3.4.7.). This indicates that they are separate and distinguishable from each other.  Yes these are serving as required egress.

      Agreed that if it was considered exterior stair then 9.5.3.3.(1) & (2) would apply and 30 min would be required. The masonry walls easily give that but then I get to 9.5.2.8. for the closures. The challenge there is that under the ‘fire escape’ definition, there are specific parameters which openings need closures but under the ‘exterior stairway’ definition, those parameters don’t exist means even an opening 60′ away horizontally away would technically need to be protected.

      The Type 3 reference is straight out of the IFSTA manual for Firefighter Level 1. I forget that everyone here doesn’t necessarily have suppression background – sorry about that. Masonry loadbearing exterior walls with combustible floors/interior walls/supporting elements/roof.

       

      Rob, I’m with George, under FPPA, we do not have the authority to order tests like the BCA provides so I can’t tell the owner to have it evaluated. What I can do is go to OBC SB2 2.1.1. and see that 76mm (3 inch) solid brick gives me 45 min. This style of construction (if brick) is typically 2 wythes minimum if not 3 or 4 wythes thick. It’s also reasonable to consider a real stone wall (similar thickness or more) with similar parameters. No need to evaluate the masonry further than that to me.

      When considering the cost of evaluation vs replacement, that’s partly where my mind is. Under 9.5.3.7. I can define exactly which openings need closures by the distances specified in Sentence (2). For argument sake, lets say that means 10 windows on the side of a long building. But now if I use 9.5.2.8. EVERY window in the side of the building needs to be protected. That could be a HUGE difference, hence this discussion.

    • #12707
      Vicki VeldmanVicki Veldman
      Participant

      George has the right answer.  If the stair is a required exit we then only worry about the construction of the stair, access to the stair and if openings have to be protected.  There is a great picture explanation sent out by the OFM that shows how to assess what openings need to be protected that I could email to anyone that wants it.  If the stair doesn’t serve above the second storey, openings don’t have to be protected.

      If the stair is not a required exit, it still has to be maintained and be safe to use.  You would use Part 2 of the fire code for the maintenance of the stair.

    • #12711
      John WilsonJohn Wilson
      Participant
      • Department Name: Perth Fire Services

      Hi Vicki,

      Thanks for the comment. Construction of the stair is easy as is maintenance of it and the ‘serving stories above the second’ clause. The question that remains unclear is WHICH openings need protected.

      9.5.3.7 paints a very clear picture of which openings around a fire escape need protected. The Code is not clear when it comes to an exterior stair which is not the same thing as a fire escape so 9.5.3.7. can’t be used to identify openings around an exterior stair.

      Exterior stair and fire escape are not interchangeable terms and they both have the ability to serve as required exits.

    • #12714
      Kevin DuncanKevin Duncan
      Participant

      Hey Jon,

      One of the major differences would be construction requirements and hence the safety factor being increased for Fire Escapes. Fire escapes tend to be constructed more narrow, steeper, etc. and quite frankly scary to walk on if you are three stories up, we have a few here. Therefore part of the increased fire protection. Exterior stairways required by Building Code would fall under building code if existing. If the stairs comply with the OBC of the day then move on and only worry about maintenance. Check with the Building Officials on whether the stairs complied or if they pre-date OBC then perhaps Part 11 of the OBC would help, either way check with them. Call it a fire escape, make sure it complies,  get the owner to agree and then go with wired glass for the window openings and be done with it, may be cheaper for the owner and you would be meeting OFC protection regulations for a fire escape –  just a thought. Be safe.

    • #12717
      John WilsonJohn Wilson
      Participant
      • Department Name: Perth Fire Services

      THANK YOU KEVIN! I never thought of looking in OBC Part 11.

      OBC 3.4.7.2. (wooden fire escape construction) has a Pt 11 CA that references 3.2.3.13.(2) which is unenclosed exterior exit stairs that prescribes protection of the openings 3m horrizontally, 10m below and 5m above which is interesting considering 3.4.7.4. only requires protection of openings 1.8m above.

      So in current OBC,  if it’s an exterior exit stair, it needs protection of openings 5m above but if it’s a fire escape, it can get by with 1.8m above. Now I’ve got to dig out my old OBCs and see how far back those 3.2.3.13. clauses go.

       

      In regards to what’s an exit stair vs fire escape, I guess it would come down to the dimensions of the rise/run and width…

      Stairs:  Max rise 200mm, min run 255mm, min width 1650mm

      Fire Escape: max rise 210mm and min run 220mm, min width can be reduced to 550mm if not more than 3 stories and not more than 15 persons

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