406.3 Replacement window emergency escape and rescue openings. Where windows are required to provide emergency escape and rescue openings in Group R-2 and R-3 occupancies, replacement windows shall be exempt from the requirements of Sections 1030.2, 1030.3 and 1030.5 provided the replacement window meets the following conditions:
1030.2 Minimum size. Emergency escape and rescue openings shall have a minimum net clear opening of 5.7 square feet (0.53 m2).
Exception: The minimum net clear opening for grade- floor emergency escape and rescue openings shall be 5 square feet (0.46 m2).
1030.2.1 Minimum dimensions. The minimum net clear opening height dimension shall be 24 inches (610 mm). The minimum net clear opening width dimension shall be 20 inches (508 mm). The net clear opening dimensions shall be the result of normal operation of the opening.
1030.3 Maximum height from floor. Emergency escape and rescue openings shall have the bottom of the clear opening not greater than 44 inches (1118 mm) measured from the floor.
1030.5 Window wells. An emergency escape and rescue opening with a finished sill height below the adjacent ground level shall be provided with a window well in accordance with Sections 1030.5.1 and 1030.5.2.
Now to examine the code that does apply:
406.3 states that replacement windows shall be exempt from the requirements of Sections 1030.2, 1030.3 and 1030.5 . That is provided:
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 shall be permitted to be 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.
The first part states that the window must be the largest that that particular manufacturer sells which will fit the opening. Since there is an opening and it is filled to the brim with window, anyone can surmise that the next size up isn't going to fit. That will usually be obvious but if an inspector is to know that, I suppose research is required. Note that there is no description of the window.
It must pass the first part and now there is a choice. One of the next two shall be met.....do that and the question is answered.
Next is that the window can be of the same operating style. That is simple to discern. What is not included is any indication that there are any restraints on the net free opening area. The only requirement is that it be of the same operating style.....the window will slide one of two ways...horizontal or vertical...maybe swing out..... that's all there is to it.
The other path to approval is a style that provides an equal or better opening area as the existing window. Now any style is granted as long as the area meets this requirement.....which is only the area of the opening.....not minimum opening dimensions. Not height from the floor. Just the area. Can it be a group of openings? As is the next part of this thread.
The previous window was a horizontal slider. A fixed pane in the middle and sliding panes of equal dimension on either side. The whole thing is a bit over 60". The actual opening area is unknown but the individual openings were undoubtedly small in comparison to the present-day egress code. The sill height is 49".
A. The new window has an opening nearing a half in each of three segments. The previous window did the same in two of the three segments. Obviously this window produces more "opening area" than the existing window.
B. Another way to look at this is to define "opening area" as a single opening and not a group. Rather than accepting a greater number of areas as contributing to the whole opening in the window. In this case the window above still meets the code in that half of a 1/3 segment opened before and does so now.
B makes better sense than A....But consider that if the window is the same "operating style" any opening is possible. Should there be an expansion on the word style? Perhaps include, "Well then it's going to open just as big as the existing". I don't see that fitting in with style or this code which clearly exempts the egress requirements.
Nothing is implied by the code. Style in the parlance of construction is hung and slider.
Some claim that style means like for like. The same operating style with the same net free opening with the same or greater width and height dimensions. The sill height would remain the same or be lower. The thinking is that the replacement window is no less compliant than was the existing window.
We took that approach some years ago. There was a problem with many retrofit windows that reduced the opening area and raised the sill height. That problem has gone away with 406.3.
If it is like for like it would have been easy enough to just say so. The wording, "operating style" is a limitation. It does not include any other parameter. If the previous use of the word style included like for like there would be no use in stating that the other style is "a style that provides for an equal or greater window opening area than the existing window."
It all seems at odds with what we do when applying code to egress windows. Something went wrong here. Can compliant egress windows be replaced with windows that are exempt from egress requirements?
If nothing else, this code is poorly written.
- 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 shall be permitted to be 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.
- The replacement of the window is not part of a change of occupancy.
1030.2 Minimum size. Emergency escape and rescue openings shall have a minimum net clear opening of 5.7 square feet (0.53 m2).
Exception: The minimum net clear opening for grade- floor emergency escape and rescue openings shall be 5 square feet (0.46 m2).
1030.2.1 Minimum dimensions. The minimum net clear opening height dimension shall be 24 inches (610 mm). The minimum net clear opening width dimension shall be 20 inches (508 mm). The net clear opening dimensions shall be the result of normal operation of the opening.
1030.3 Maximum height from floor. Emergency escape and rescue openings shall have the bottom of the clear opening not greater than 44 inches (1118 mm) measured from the floor.
1030.5 Window wells. An emergency escape and rescue opening with a finished sill height below the adjacent ground level shall be provided with a window well in accordance with Sections 1030.5.1 and 1030.5.2.
Now to examine the code that does apply:
406.3 states that replacement windows shall be exempt from the requirements of Sections 1030.2, 1030.3 and 1030.5 . That is provided:
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 shall be permitted to be 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.
The first part states that the window must be the largest that that particular manufacturer sells which will fit the opening. Since there is an opening and it is filled to the brim with window, anyone can surmise that the next size up isn't going to fit. That will usually be obvious but if an inspector is to know that, I suppose research is required. Note that there is no description of the window.
It must pass the first part and now there is a choice. One of the next two shall be met.....do that and the question is answered.
Next is that the window can be of the same operating style. That is simple to discern. What is not included is any indication that there are any restraints on the net free opening area. The only requirement is that it be of the same operating style.....the window will slide one of two ways...horizontal or vertical...maybe swing out..... that's all there is to it.
The other path to approval is a style that provides an equal or better opening area as the existing window. Now any style is granted as long as the area meets this requirement.....which is only the area of the opening.....not minimum opening dimensions. Not height from the floor. Just the area. Can it be a group of openings? As is the next part of this thread.
The previous window was a horizontal slider. A fixed pane in the middle and sliding panes of equal dimension on either side. The whole thing is a bit over 60". The actual opening area is unknown but the individual openings were undoubtedly small in comparison to the present-day egress code. The sill height is 49".
A. The new window has an opening nearing a half in each of three segments. The previous window did the same in two of the three segments. Obviously this window produces more "opening area" than the existing window.
B. Another way to look at this is to define "opening area" as a single opening and not a group. Rather than accepting a greater number of areas as contributing to the whole opening in the window. In this case the window above still meets the code in that half of a 1/3 segment opened before and does so now.
B makes better sense than A....But consider that if the window is the same "operating style" any opening is possible. Should there be an expansion on the word style? Perhaps include, "Well then it's going to open just as big as the existing". I don't see that fitting in with style or this code which clearly exempts the egress requirements.
Nothing is implied by the code. Style in the parlance of construction is hung and slider.
Some claim that style means like for like. The same operating style with the same net free opening with the same or greater width and height dimensions. The sill height would remain the same or be lower. The thinking is that the replacement window is no less compliant than was the existing window.
We took that approach some years ago. There was a problem with many retrofit windows that reduced the opening area and raised the sill height. That problem has gone away with 406.3.
If it is like for like it would have been easy enough to just say so. The wording, "operating style" is a limitation. It does not include any other parameter. If the previous use of the word style included like for like there would be no use in stating that the other style is "a style that provides for an equal or greater window opening area than the existing window."
It all seems at odds with what we do when applying code to egress windows. Something went wrong here. Can compliant egress windows be replaced with windows that are exempt from egress requirements?
If nothing else, this code is poorly written.
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