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R310.1 Non-habitalbe Basement

Francis Vineyard

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Jan 1, 2010
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Charlottesville, VA
Is it the intent of Section R310.1 to require EERO in habitable (finished or unfinished) basements only?

Have plans designating basements with access through a garage; no windows or stairs to the residence.

[RB] HABITABLE SPACE. A space in a building for living, sleeping, eating or cooking. Bathrooms, toilet rooms, closets, halls, storage or utility spaces and similar areas are not considered habitable spaces.

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.

Exception: Storm shelters and basements used only to house mechanical equipment not exceeding a total floor area of 200 square feet (18.58 m2).

R311.4 Vertical egress.
Egress from habitable levels including habitable attics and basements not provided with an egress door in accordance with Section R311.2 shall be by a ramp in accordance with Section R311.8 or a stairway in accordance with Section R311.7.

E3902.5 Unfinished basement receptacles.
125-volt, single-phase, 15- and 20-ampere receptacles installed in unfinished basements shall have ground-fault circuit-interrupter protection for personnel. For purposes of this section, unfinished basements are defined as portions or areas of the basement not intended as habitable rooms and limited to storage areas, work areas, and similar areas. [210.8(A)(5)]
 
Agree with steveray, over 200 SF, it is still a basement.

Then you have to deal with;

Emergency escape and rescue openings shall open directly into a public way, or to a yard or court that opens to a public way.

Going through the garage is not directly, does not really fit the requirement.
 
I'm having second thoughts since we've recently had several plans designating basements with daylight garages but after completion ended up being the first story owing to the upper level being more than 6 ft. above grade plane .

Would this change your mind if it were not a basement?

Thanks in advance for your feedback.

 
The floor area of the basement exceeds 200 s.f..
The IRC does not address divided basement spaces (unless bedrooms are included). The common passageway and storage rooms A & B are one contiguous basement area.
 
They don't call them out as storage or bedroom, they used UNITS A&B. That to me in it's self is sketchy and very easily become bedrooms after CO. Your call but I would Go with EERO's.
 
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Thanks for posting the drawing - until I saw that I was saying to myself why did the code ever come up with 200 sf is ok but 201, 202... 250...275 etc can not be ok - what would have changed? My great grandfather would been able to store more wine down there. After years of crawling in crawl spaces I would rather have crawl spaces that are 6 of 7 feet tall so I could do walking underfloor inspections - nope it seams that I can only walk upright in 200 sf.
one hour partition? tennant separation between unit A & B? now those notes along with "Unit A and Unit B" have my curiosity up.
 
I would require written/labeled clarification of Unit A & Unit B.

As far as exiting through a garage, our stance is whether on grade or stair from a lower level up to grade we do not allow it. The garage would have to be partitioned off, such as a hallway with a man door directly to the exterior. Now the hallway can have another man door into the garage which most builders and homeowners understand after an explanation.
 
I would require written/labeled clarification of Unit A & Unit B.

As far as exiting through a garage, our stance is whether on grade or stair from a lower level up to grade we do not allow it. The garage would have to be partitioned off, such as a hallway with a man door directly to the exterior. Now the hallway can have another man door into the garage which most builders and homeowners understand after an explanation.
Agreed however in reference R311.4; "Egress from habitable levels including habitable attics and basements" but these "basement" spaces cannot be made habitable.

R310.1 as worded apparently does not specify an exemption for basement used for only storage; thus my question do you think this is the intent?

The C.O. will note this level as storage whether or not the final grade has it as a basement.
 
I contend Unit A and B are intended to be habitable spaces based on the information provided and triggering the egress.
1. Unit A.
2. Unit B.
3. Rated wall assembly

It likely is a stance that you will not win but its a method you can use to clarify in your records this was thoroughly reviewed on your behalf and based on the total of information received there was nothing further you could or could not enforce. Wait hold the phone!!!
 
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What code edition are you in? I assume the language you provided is modified from the IRC being that 310.1 in IRC starts off listing Basements, Habitable attics,...
With Basement comma the intent I believe is a basement shall have a direct egress, such as hallway/corridor through garage.
 
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Francis
Is there a 3'0" egress door to get out of the basement?
Finished or unfinished is irrelevant to the definition of habitable.
Units "A" or "B" could be used for an office or reloading room. craft room or any number of "activities" a family member would do while "living" in there home.

At a minimum there should be a egress door in the basement since there is no direct access to the upper residential portion
R311.1 Means of egress.
All dwellings shall be provided with a means of egress as provided in this section. The means of egress shall provide a continuous and unobstructed path of vertical and horizontal egress travel from all portions of the dwelling to the exterior of the dwelling at the required egress door without requiring travel through a garag
 
What code edition are you in? I assume the language you provided is modified from the IRC being that 310.1 in IRC starts off listing Basements, Habitable attics,...
With Basement comma the intent I believe is a basement shall have a direct egress, such as hallway/corridor through garage.

Isn't this as two different requirements?
1) R310.1 (EERO) apparently applies even if the basement is non-habitable;
2) R311.4 (R311.2) required only if the basement is habitable.

It seems contradictory to me if the storage space was not a basement.
 
the applicant needs to be convinced to have a full sized door leading to the exterior to solve EERO (which also solves the proper means of egress for a basement). Then if they still want a door for garage/basement space they could. I am still curious about the rated partition.
Every space built has an intended use getting the applicant to tell us the full story is often diffficult
 
The rated partitions are because this is a stacked 2-family dwelling. Unit B is the level above unit A with the one-hour separation between units. I suppose for those that usually see a split side by side would not be familiar with variants of this type of configuration.

Additionally Virginia amended the IRC to provide an interior passage for accessibility. The designer volunteered to provide the van accessible parking for unit A in the garage.

For those unfamiliar with the abbreviation FPSC; Fire Protected Self-Closing door.

Hope this explanation satisfies those who were curious.
 
Francis,

My understanding of the two sections:
R310.1, General requirement for spaces
R311.4, Specific requirement regarding habitable spaces in the basement such as but not limited to bedrooms.

IMO, all basement constructed under current code require an egress directly to the exterior per R310.1.

The language in the 2015 IRC has been changed from previous editions for R311.4, speaks to ramps and stairs as egress. Also, R310.1 language has been clarified and I do think with these changes/clarifications the intent is to require all basements to have direct egress to the exterior and if they throw a bedroom then a direct egress is required within the bedroom.

With your scenario of two separate dwellings, my call would be to require direct egress to exterior through hall/corridor.
 
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