Must a window in a proposed basement habitable space conform to code even if it is not required to be in the space?

Question

I am looking to create a finished space in my basement. The plans are for a habitable room within my basement (non-sleeping) to be used as an office. The plans exceed horizontal width requirements, and the ceiling exceeds 7ft. Contained within the room is a 32 x 15.5 inch egress window that was one of two such egresses installed original to the house. I have attached a rough drawing of the proposed layout.

However, my plans were sent back to me by the local planning office (I'm in Western NY) as needing to be modified due to being out of compliance with the following code rules of the 2018 IRC:

R303.1 Habitable rooms.

Habitable rooms shall have an aggregate glazing area of not less than 8 percent of the floor area of such rooms. Natural ventilation shall be through windows, skylights, doors, louvers or other approved openings to the outdoor air. Such openings shall be provided with ready access or shall otherwise be readily controllable by the building occupants. The openable area to the outdoors shall be not less than 4 percent of the floor area being ventilated.

Exceptions:

1.The glazed areas need not be openable where the opening is not required by Section R310 and a whole-house mechanical ventilation system is installed in accordance with Section M1505.

2.The glazed areas need not be installed in rooms where Exception 1 is satisfied and artificial light is provided that is capable of producing an average illumination of 6 footcandles (65 lux) over the area of the room at a height of 30 inches (762 mm) above the floor level.

3.Use of sunroom and patio covers, as defined in Section R202, shall be permitted for natural ventilation if in excess of 40 percent of the exterior sunroom walls are open, or are enclosed only by insect screening.

R310.1 Emergency escape and rescue opening required.

Basements, habitable attics and every sleeping room shall have not less than one operable emergency escape and rescue opening. Where basements contain one or more sleeping rooms, an emergency escape and rescue opening shall be required in each sleeping room. Emergency escape and rescue openings shall open directly into a public way, or to a yard or court that opens to a public way.

R305.1 Minimum height.

Habitable space, hallways and portions of basements containing these spaces shall have a ceiling height of not less than 7 feet (2134 mm). Bathrooms, toilet rooms and laundry rooms shall have a ceiling height of not less than 6 feet 8 inches (2032 mm).

Exceptions:

1.For rooms with sloped ceilings, the required floor area of the room shall have a ceiling height of not less than 5 feet (1524 mm) and not less than 50 percent of the required floor area shall have a ceiling height of not less than 7 feet (2134 mm).

2.The ceiling height above bathroom and toilet room fixtures shall be such that the fixture is capable of being used for its intended purpose. A shower or tub equipped with a showerhead shall have a ceiling height of not less than 6 feet 8 inches (2032 mm) above an area of not less than 30 inches (762 mm) by 30 inches (762 mm) at the showerhead.

3.Beams, girders, ducts or other obstructions in basements containing habitable space shall be permitted to project to within 6 feet 4 inches (1931 mm) of the finished floor.

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To the best of my understanding, my plans as they stand should comply so long as:

• I have mechanical ventilation installed in the new room in accordance with M1505
• Lighting that conforms to the standards laid out in Exception 2 of R303.1
• A ceiling height that conforms to, or exceeds, the height minimum set out in R305.1 (which I do, ceiling height is 7ft 10")

Because I have another egress window in the basement and mechanical ventilation system installed, I meet exception 1 of R303.1, and because I plan to install lighting that will meet the standards of Exception 2 of R303.1, which to me indicates that the egress window in the proposed office space is not required.

However, given that the window is indeed there already, must this window conform to R303.1 simply by existing? Can I meet the requirements of exceptions 1 and 2, but still have the window in place, meaning it is not a code consideration?

This is my best understanding of it as it is worded, however I wanted to get some additional opinions.

Thanks.

Update 1: The building inspector got back to me and confirmed that the window would be taken out of consideration for compliance if Exceptions 1 and 2 were met, however I would need to accommodate a means to get fresh air into the habitable space given the lack of an openable window as far as the inspection would be concerned. A fresh air mixing box attached to the air return would be deemed acceptable in this case.

Answer 1

I'm only reading what you wrote. IDK NY code.

Where basements contain one or more sleeping rooms, an emergency escape and rescue opening shall be required in each sleeping room. Emergency escape and rescue openings shall open directly into a public way, or to a yard or court that opens to a public way.

No exceptions.

The staircase doesn't count because it doesn't open to a public way. Unless there's an exterior door in each sleeping room then they all need an egress window.

It doesn't matter as long as each sleeping room has a door (obviously) and an escape window.

If you're asking if they all have to be egress, I don't think so.

If you're asking if the common area, of what's left of the basement, needs its own egress... well it doesn't say that, and with two down there I wouldn't think so.

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Exception 2 of R303.1, which to me indicates that the egress window in the proposed office space is not required.

That exception is for lighting concerns, not egress. I'm not 100% on this but if the 'office' has a closet it's now a sleeping room, which would need an egress window. I'd ask them what a "sleeping room" is.

I plan to install lighting that will meet the standards

Your approved electrical plan is presumably one of the things they're after.

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I'd ignore that window entirely, the 'fact' that's it's an 'office' and just do what code says.

Answer 2

Revised:

2018 IRC R303.1 Code Text: Habitable rooms shall have an aggregate glazing area (total) of not less than 8 percent of the (total) floor area of such rooms. Natural ventilation shall be through windows, skylights, doors, louvers or other approved openings to the outdoor air. The openable area to the outdoors shall be not less than 4 percent of the floor area being ventilated. Exceptions allow the use of artificial light and mechanical ventilation.

A notable warning from a web source:

Remodeler: if you have an existing home and you add a sleeping room, or finish a separate living space in the basement, the code requires that you install an egress window to serve these spaces. Without a means of egress, these rooms can represent a dangerous fire trap if you do not have a quick and easy to operate emergency egress escape window. If you have a basement that has a bedroom, recreation room, den, family room, media room, office, or home gym. All of these rooms are required to have a means of egress.

Comments:

So, appraently you are facing two issues here:

1. Do you have glazed area totaling 8% of the entire floor area, as the addition of the office space classifys the entire basement as a "hibitable space", which more restrict rules apply.

2. Following the same line, does the "hibitable spaces" meeting the requirement of code section R310.1 that says:

Basements, habitable attics and every sleeping room shall have not less than one operable emergency escape and rescue opening. Where basements contain one or more sleeping rooms, an emergency escape and rescue opening shall be required in each sleeping room. Emergency escape and rescue openings shall open directly into a public way, or to a yard or court that opens to a public way.

If I didn't make mistake, the existing window does not meet the code definition of an escape/rescue window, which requires:

• The bottom of the egress window opening can't exceed 44" from the finished floor. (As noted, your window is 78" from the floor)

• The minimum opening area of the egress window is 5.7 square feet. (The area of the 32"(W)x15.5(H)" window is 3.47 square feet)

• The minimum egress window opening height is 24" high. (Your window height is 15.5")

• The minimum egress window opening is 20" wide.

• The egress window must have a glass area of not less than 8% of the total floor area of room(s) for which it is servicing, to allow the minimum amount of sufficient natural light. *

• The egress window must have a opening area of not less than 4% of the total floor area of room(s) for which it is servicing, to allow the minimum amount of natural ventilation. (*)

(*) Multiple windows can be used to service a single area where one window does not meet these percentages of total floor area. As long as the totaled amounts from this combination of windows meet or exceed the 8% for natural light and 4% for natural ventilation.

Conclusion:

1. You need to have a gross (aggregate) glazed area that is at least equal to 8% of the entire floor area. If a glazed window is installed in the office space, it can be a fixed pan window if meets "Exception 1"; if the requirement of a glazed area in the room is waived per "Exception 2", you have to make sure the totaling of the glazed area in other space(s) meets the 8% requirement.

2. You need to make sure you have at least one escape opening (openable) that meets the code requirement.

Note: The area of the qualified escape opening and the existing window(s) (though not qualified as the means of escape) can be added together to satisfy the 8% requirement.

Hope this helps.

Answer 3

Yes, the existing windows may remain if the other items noted in the Permit Review are satisfied.

In your first paragraph you call the existing windows “egress windows”. They are not “egress windows” and they don’t need to be.

The Code says that “alterations shall conform to that required for new construction without requiring the existing structure to comply with all the requirements of this Code. And the alterations cannot create “unsafe conditions “. Unsafe conditions are identified as structurally unsafe, not provide adequate egress, create fire hazard, will reduce required fire resistance, or will create conditions dangerous to human life. (See R102.7.1 ) Clearly, having extra windows do not create any of those issues.

In addition, the “Purpose of this code is to provide minimum requirements to safeguard the public safety, health, and general welfare, through affordable structural strength, means of egress, stability, sanitation, light and ventilation, energy conservation and safety to life and property from fire and other hazards attributed to the built environment.” ((See R101.4) So, again, having extra windows do not create any of those issues.

Creating minimum requirements to comply with the current code does not mean other things need to be removed unless they create one of the issues listed: structural stability, safety, etc.

Egress windows are required in sleeping rooms, not in every habitable room. Habitable rooms require ventilation and you can provide that with operable windows of a certain size or with a mechanical system, as outlined.

Before you resubmit, I’d call and talk to the reviewers and let them know what you plan on doing. They’ll help you. They want you to get it right too.