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Safety glazing window 3rd floor?

D

DNW-KW

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Joined
Oct 10, 2022
Messages
4
Location
Washington
Do windows at 3rd level (which have sill at 36" above finish floor) need to be safety glazing? What code section? It's implied in 2406.4.3 (but that's an exception to a 9 SF condition that smaller windows don't meet).
 
2406.4.3 Glazing in Windows
Glazing in an individual fixed or operable panel that meets all of the following conditions shall be considered to be a hazardous location:
1. The exposed area of an individual pane is greater than 9 square feet (0.84 m2).
2. The bottom edge of the glazing is less than 18 inches (457 mm) above the floor.
3. The top edge of the glazing is greater than 36 inches (914 mm) above the floor.
4. One or more walking surface(s) are within 36 inches (914 mm), measured horizontally and in a straight line, of the plane of the glazing.

Not sure exactly what your situation is, what's the concern? Basically they're looking to avoid large shards of glass falling on people.
 
Section 2406.4.3 establishes the four criteria that must be met to require safety glazing. If a window does not meet any one of those conditions, then it is not required to have safety glazing.

Assuming a window does meet all four conditions and it is located more than 25 feet above a walking surface below, then the outside lite of an insulated glazing unit (and only the outside lite) can be non-safety glazing. The inside lite must still be safety glazing.
 
Level 3 bedroom egress windows (< 9 SF) occur where greater than 25’ above adjacent grade outside. Sills at Level 3 are 36” above finish floor.
  1. Are these windows required to have safety glazing? Code section?
  2. Are these windows required to have indoor ‘guard’ fall protection since sill is 36” but < 42” guard height requirement? Code section?
 
DNW-KW said:
Level 3 bedroom egress windows (< 9 SF) occur where greater than 25’ above adjacent grade outside. Sills at Level 3 are 36” above finish floor.
  1. Are these windows required to have safety glazing? Code section?
  2. Are these windows required to have indoor ‘guard’ fall protection since sill is 36” but < 42” guard height requirement? Code section?
Click to expand...
1. No. If less than 9 sq. ft., one of the four criteria is not met; thus, no safety glazing is required (Section 2406.4.3).,
2. No. Section 1015.8 states the bottom of the clear opening must be less than 36 inches to require protection--if at 36 inches, it is not subject to the requirements.

If the window clear opening was less than 36 inches, several options are provided in Section 1015.8; however, subparagraphs 3 and 4 can be used for emergency escape and rescue openings. Subparagraph 3 addresses a fall prevention device, and subparagraph 4 addresses a window-opening control device (WOCD). The former is a device attached to the window that covers or blocks the opening until it can be released for escape. The latter is a hardware device that only allows the opening of the window to prevent a 4-inch sphere from passing through but can be disengaged to allow full opening of the window.

The intent of the protection is not to prevent adults from falling through the window but to prevent children from falling through. Both methods require some level of special knowledge to open the window to its full required area.
 
RLGA said:
then the outside lite of an insulated glazing unit (and only the outside lite) can be non-safety glazing. The inside lite must still be safety glazing.
Click to expand...
That seems odd. As soon as the inside pane disappears, the outside pane is then the inside pane and a violation. So I will have to disagree.
 
ICE said:
That seems odd. As soon as the inside pane disappears, the outside pane is then the inside pane and a violation. So I will have to disagree.
Click to expand...
If the inside panel is safety glazed then it won't break so there is no need for the outer pane to also be safety glazed.
 
ICE said:
It breaks.
Click to expand...
If you hit a concrete masonry wall hard enough, it, too, will break.

Safety glass is intended to resist human impact. Throw a heavy metal chair at it and it might break. If the inside glass lite breaks, it will need to be replaced, just like any other building safety feature.
 
Twenty-five feet seems to be an arbitrary dimension. Why not ten feet?
 
I don't think safety glass is required in your case but #2 is the easiest fix if required by the inspector.

Exceptions:
1. Decorative glazing.
2. Where glazing is adjacent to a walking surface
and a horizontal rail is installed 34 to
38 inches (864 to 965 mm) above the walking
surface. The rail shall be capable of
withstanding a horizontal load of 50
pounds per linear foot (730 N/m) without
contacting the glass and have a cross-sectional
height of not less than 11/2 inches (38
mm).
3. Outboard panes in insulating glass units
and other multiple glazed panels where the
bottom edge of the glass is 25 feet (7620
mm) or more above grade, a roof, walking
surfaces or other horizontal [within 45
degrees (0.79 rad) of horizontal] surface
adjacent to the glass exterior.

You could but the rail against the 36" high windowsill (or make 1 1/2" thick wood windowsill) to comply.;)
 
I think I am with ICE on the 2 panel thing.....Other than locations covered by 2406.4.3

It doesn't say the "exposed" panel or anything like that and I am not sure it qualifies as any of the exemptions as far as guards 2406.4.7/ walls 2406.4.2 or whatever else....Ron, any idea why they didn't carry that to other locations?
 
ICE said:
Twenty-five feet seems to be an arbitrary dimension. Why not ten feet?
Click to expand...
A majority of the requirements in the code are arbitrary. I have been told (anecdotally) that the allowable building areas were initially made up without any detailed objective analysis. Code requirements have evolved since based on real-world events and more objective analysis. Some requirements have been fine-tuned to be less arbitrary and new arbitrary requirements have been added to possibly be fine-tuned in the future.

If you can provide an objective analysis to prove that a 25-foot height is too high, then submit a code change proposal with your data attached and it will be considered.
 
steveray said:
I think I am with ICE on the 2 panel thing.....Other than locations covered by 2406.4.3

It doesn't say the "exposed" panel or anything like that and I am not sure it qualifies as any of the exemptions as far as guards 2406.4.7/ walls 2406.4.2 or whatever else....Ron, any idea why they didn't carry that to other locations?
Click to expand...
Regarding 2406.4.7, I agree that the exception to 2406.4.3 would not apply since the exception only addresses glazing under those conditions. Section 2406.4.7 is a more specific condition than the general conditions in Section 2406.4.3, and the more specific one takes precedence over the general (Section 102.1). I assume the exception was not applied to Section 2406.4.7 because a person moving down the stairs has more kinetic energy than a person walking laterally; thus, the impact is potentially greater for the person walking down the stairs.

As to Section 2406.4.2, the exception to 2406.4.3 would not apply for the same specific versus general requirements provision mentioned above. However, there is probably a more logical reason why the exception was not included in this section. It is evident, due to the presence of a door, that both sides of the IGU are immediately adjacent to walking areas, and the exterior side would not be more than 25 feet above a walking surface. Otherwise, it would be a helluva drop to use that door!
 
steveray said:
Soooooo....When the outer pane shatters, by the time it falls 25' it's not a problem? Not sure why the height is a thing on that one...
Click to expand...
According to the building code, yes.

It depends on the direction of the force applied to the glazing unit. At a high distance, the impact on the glass unit is most likely from the interior; thus, the inside lite is required to be safety glass. It is assumed that the safety glazing will be sufficient to resist any force from being applied to the non-safety glass lite on the exterior.

At 25 feet, it is assumed that the exterior lite of an IGU would not be readily subject to a force that would cause the glass to break.

However, there are other things that could supplant the exception:
  • Wind Loads - may require stronger glass to prevent deflection greater than that permitted.
  • Windborne Debris Regions - In areas so designated, glazing is required to comply with Section 1609.2.
  • Differential Shading - Although not a code requirement, glass lites partially exposed to sunlight and shading will have different expansion rates that cause unequal forces within the glass causing breakages. This is sometimes overcome by using tempered (safety glass) or heat-strengthened (non-safety glass, but stronger than annealed glass) to counteract the differential stresses.
 
Would this mean that when they use the film that 3 M makes that they can use instead of tempered glass would also be required on the outside glass if less than 25" above grade?

3. Outboard panes in insulating glass units
and other multiple glazed panels where the
bottom edge of the glass is 25 feet (7620
mm) or more above grade, a roof, walking
surfaces or other horizontal [within 45
degrees (0.79 rad) of horizontal] surface
adjacent to the glass exterior.
 
Rick18071 said:
Would this mean that when they use the film that 3 M makes that they can use instead of tempered glass would also be required on the outside glass if less than 25" above grade?

3. Outboard panes in insulating glass units
and other multiple glazed panels where the
bottom edge of the glass is 25 feet (7620
mm) or more above grade, a roof, walking
surfaces or other horizontal [within 45
degrees (0.79 rad) of horizontal] surface
adjacent to the glass exterior.
Click to expand...
In regards to the "large pane" section we are talking about....yes....I rarely actually see it so I haven't thought much about it before now....the 25' must because of stuff hitting it from the outside (rocks/ balls/ etc.)

My earlier comment was thinking about the inner pane vs. outer pane and that was confusing and I think still maybe not addressed well...
 
2604.4.3 exception 3 confuses me. It looks like outboard panes meeting conditions 1 - 4 must be safety glass if they are less than 25 feet above grade, but don't have to if they are more than 25 feet above grade.
 
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