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Egress window sill height

alaskajoe

Registered User
Joined
May 22, 2019
Messages
53
Location
Alaska
I have a sill height of 44" but code says clear opening is where the measurement is taken. With the bottom rail the clear opening is 46". Would a 12" deep by 4" tall step for the full width of the window be acceptable. I would have it solidly affixed to the floor and wall. I realize anything can be removed at any time in the future but on inspection it would meet the intent of the code.
 
Our code states the 44" is "measured from the "floor". We would not accept a step. However, we have accepted raised floor areas (ie., landings) that are as wide as the window opening, and at least 36" deep
 
If you have the 5.7 sf. and 20" W by 24" H clear opening you still meet the minimum. The grade floor openings have the exc. to only have 5.0 sf of opening.
 
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Our code states the 44" is "measured from the "floor". We would not accept a step. However, we have accepted raised floor areas (ie., landings) that are as wide as the window opening, and at least 36" deep
This is our interpretation as well. A step does not constitute a floor area.
 
If you have the 5.7 sf. and 20" W by 24" H clear opening you still meet the minimum. The 44" is for the exc. to only have 5.0 sf of opening.
Huh?

R310.2.2 Window Sill Height
Where a window is provided as the emergency escape and rescue opening, it shall have a sill height of not more than 44 inches (1118 mm) above the floor; where the sill height is below grade, it shall be provided with a window well in accordance with Section R310.2.3.
 
Here we are again in the mud wrestling with the same guy. He says a fixed permanent 12" step in front of the windows meets the intent of the code. I am going with a 36" landing the width of the windows or lower the window is what I want. No comply no CO. If this was a remodel or an attempt at code upgrades ,maybe, but there is no excuse on new construction. Am I being too harsh?
 
Also be wary of replacement windows installed within the existing sill which may raise the height.
 
2012 IRC
Where emergency escape and rescue openings are provided they shall have a sill height of not more than 44 inches (1118 mm) measured from the finished floor to the bottom of the clear opening.

The 2012 was very confusing since the clear opening and the sill height usually are not the same. The 2018 uses the sill height to determine code compliance and you measure from the floor not a step

2018 IRC
R310.2.2 Window sill height.
Where a window is provided as the emergency escape and rescue opening, it shall have a sill height of not more than 44 inches (1118 mm) above the floor;
 
2016 CA Residential Code R310.2.5 Replacement windows

Replacement windows installed in buildings meeting the scope of this code shall be exempt from the maximum sill height requirements of Sections R310.1 and Sections R310.2.1 and R310.2.2, provided the replacement window meets the following conditions:
  1. The replacement window is the manufacturer’s largest standard size window that will fit within the existing frame or existing rough opening. The replacement window is of the same operating style as the existing window or a style that provides for an equal or greater window opening area than the existing window.
  2. The replacement window is not part of a change of occupancy.
 
I am confused as to your responsibility on this project. Your last post indicates that you want the window to be lowered and it is new construction. It sounds like your the homeowner? If that is the case I would require them to lower the window to provide a code compliant situation. The step/landing is a band aid for a improperly installed window. also 12" tall step? how is that compliant? Have them do it right.
 
We allow a step...

(Amd) R310.2.2 Window sill height. Where a window is provided as the emergency escape and
rescue opening, it shall have a sill height of not more than 44 inches (1118 mm) above the floor;
where the sill height is below grade, it shall be provided with a window well in accordance with
Section R310.2.3.
Exception: The 44-inch (1118 mm) maximum sill height shall be permitted to be measured
vertically above a fixed, permanent platform, step or steps whose minimum width shall equal
or exceed the operable width of the opening and shall be centered on such opening and which
shall comply with Sections R311.7.5.1 and R311.7.5.2. Glazing in windows complying with
this exception shall not be subject to the provisions of Section R308.4.6 or R308.4.7.
 
A little back story on the window well. Originally in the Fire prevention code and as such, a way for rescuing the occupants from within. The 3 square area if memory serves me well, is for a firefighter with running gear to be able to enter the SFD. Several code cycles back the window well was introduced into the residential code along with all the requirements for height, width, etc. When looking at it from the depth of the window well being over 44 inches, what does the code require? rung/ladder type of exiting apparatus. What is the difference inside the home? The ability to get out. In a former jurisdiction, applying a rung to the framed wall that allows escape was considered a viable option instead of a box stair or landing, granted this is in an existing condition. In new construction, no way nor no excuse on the builder. I suppose a code modification could substitute in that case if the BO accepts it as such.
Some years ago during an inspection for a renovation, the window opening met the height requirement, but the window was, I swear 2 feet deep (double block wall) and you really had to make a grab to get to the window. A semi/permeant step fixed the problem basically bolted to the floor and lagged to the stud wall....:rolleyes:
 
If the contractor can't get the window sill height, might want to check the window egress measurements. In the future maybe this guys plans need a call out so it doesn't have to be revisited? This isn't anything new, been in the code for awhile.
 
We allow a step...

(Amd) R310.2.2 Window sill height. Where a window is provided as the emergency escape and
rescue opening, it shall have a sill height of not more than 44 inches (1118 mm) above the floor;
where the sill height is below grade, it shall be provided with a window well in accordance with
Section R310.2.3.
Exception: The 44-inch (1118 mm) maximum sill height shall be permitted to be measured
vertically above a fixed, permanent platform, step or steps whose minimum width shall equal
or exceed the operable width of the opening and shall be centered on such opening and which
shall comply with Sections R311.7.5.1 and R311.7.5.2. Glazing in windows complying with
this exception shall not be subject to the provisions of Section R308.4.6 or R308.4.7.
What year is that exception in?
 
A little back story on the window well. Originally in the Fire prevention code and as such, a way for rescuing the occupants from within. The 3 square area if memory serves me well, is for a firefighter with running gear to be able to enter the SFD. Several code cycles back the window well was introduced into the residential code along with all the requirements for height, width, etc. When looking at it from the depth of the window well being over 44 inches, what does the code require? rung/ladder type of exiting apparatus. What is the difference inside the home? The ability to get out. In a former jurisdiction, applying a rung to the framed wall that allows escape was considered a viable option instead of a box stair or landing, granted this is in an existing condition. In new construction, no way nor no excuse on the builder. I suppose a code modification could substitute in that case if the BO accepts it as such.
Some years ago during an inspection for a renovation, the window opening met the height requirement, but the window was, I swear 2 feet deep (double block wall) and you really had to make a grab to get to the window. A semi/permeant step fixed the problem basically bolted to the floor and lagged to the stud wall....:rolleyes:
A little more "back-story" per ICC
The dimensions prescribed in the code for emergency escape and rescue openings in Sections R310.2 through R310.2.2, and as illustrated in Commentary Figure R310.2.1, are based, in part, on extensive testing by the San Diego Building and Fire Departments to determine the proper relationships of the height and width of window openings to adequately serve for both rescue and escape. The minimum of 20 inches for the width is based on two criteria: the width necessary to place a ladder within the window opening and the width necessary to admit a fire fighter with full rescue equipment, including a breathing apparatus. The minimum 24-inch (610 mm) height is based on the minimum size necessary to admit a fire fighter with full rescue equipment. By requiring a minimum net clear opening size of at least 5.7 square feet, the code provides for an opening of adequate dimensions. To be accessible from the interior of the sleeping room, attic or basement, Section R310.2.2 requires that the emergency escape and rescue opening be located not more than 44 inches above the floor. The measurement is to be taken from the floor to the bottom of the clear opening.
 
Then why do they call it emergency escape?

Definition of escape
(Entry 1 of 3)

intransitive verb

1a: to get away (as by flight)escaped from prison
b: to issue from confinement-gas is escaping
cof a plant : to run wild from cultivation
2: to avoid a threatening evil the boat sank but the crew escaped
transitive verb

1: to get free of : break away from escape the jungleescape the solar system
2: to get or stay out of the way of : AVOID efforts to escape poverty
3: to fail to be noticed or recallable by his name escapes me
4a: to issue from a smile escaped me
b: to be uttered involuntarily by a sigh of relief escaped her
escape

noun
Definition of escape (Entry 2 of 3)

1: an act or instance of escaping: such as
a: flight from confinement
b: evasion of something undesirable
c: leakage or outflow especially of a fluid
d: distraction or relief from routine or reality
2: a means of escape
3: a cultivated plant run wild
4or less commonly Escape : ESCAPE KEY
escape

adjective
Definition of escape (Entry 3 of 3)

1: providing a means of escape escape literature
2: providing a means of evading a regulation, claim, or commitment an escape clause in a contract
 
Then why do they call it emergency escape?
Definition of escape

(Entry 1 of 3)
intransitive verb
1a: to get away (as by flight)escaped from prison
b: to issue from confinement-gas is escaping
cof a plant : to run wild from cultivation
2: to avoid a threatening evil the boat sank but the crew escaped
transitive verb
1: to get free of : break away from escape the jungleescape the solar system
2: to get or stay out of the way of : AVOID efforts to escape poverty
3: to fail to be noticed or recallable by his name escapes me
4a: to issue from a smile escaped me
b: to be uttered involuntarily by a sigh of relief escaped her
escape
noun
Definition of escape (Entry 2 of 3)
1: an act or instance of escaping: such as
a: flight from confinement
b: evasion of something undesirable
c: leakage or outflow especially of a fluid
d: distraction or relief from routine or reality
2: a means of escape
3: a cultivated plant run wild
4or less commonly Escape : ESCAPE KEY
escape
adjective
Definition of escape (Entry 3 of 3)
1: providing a means of escape escape literature
2: providing a means of evading a regulation, claim, or commitment an escape clause in a contract
R310.1 Emergency escape and rescue opening required
Untitled.png

Got to save that rescue dummy....
 
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