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Stairs to a Sunroom

E

Energystar

SAWHORSE
Joined
Aug 26, 2020
Messages
99
Location
Kansas
Are stairs to a sunroom considered interior as with garage steps according to the exception in R311.7.6? Specifically, must I have a landing at the top of the stairs to the sunroom (assuming 3 risers)?

R301.2.1.1.1 has 5 different classifications for sunrooms. A class I could be as simple as a covered patio. Is this a point of egress to a public way or yard? Must the sunroom be enclosed (say screened in with a door) in order to avoid the landing?
 
I don't know what code you need to go by but this is what the 2018 IRC requires if it is not the Means of Egress (front door):
If the stairway is exterior it does not matter if it is a sunroom or deck or if there is a roof or not, it's all the same.

R311.3.2 Floor elevations at other exterior doors.
Doors other than the required egress door shall be provided
with landings or floors not more than 73/4 inches
(196 mm) below the top of the threshold.
Exception: A top landing is not required where a stairway
of not more than two risers is located on the exterior
side of the door, provided that the door does not
swing over the stairway.
R311.3.3 Storm and screen doors. Storm and screen
doors shall be permitted to swing over exterior stairs and
landings.

R311.7.6 Landings for stairways. There shall be a floor
or landing at the top and bottom of each stairway. The
width perpendicular to the direction of travel shall be not
less than the width of the flight served. For landings of
shapes other than square or rectangular, the depth at the
walk line and the total area shall be not less than that of a
quarter circle with a radius equal to the required landing
width. Where the stairway has a straight run, the depth in
the direction of travel shall be not less than 36 inches (914
mm).
Exception: A floor or landing is not required at the top
of an interior flight of stairs, including stairs in an
enclosed garage, provided that a door does not swing
over the stairs.
 
I suppose that is the crux of the question. What determines whether the stair is interior or exterior?
 
The sunroom is Class IV. So, weather tight with plastic windows and thermally isolated from the habitable space.

So, if the sunroom were class I, screened in with a screen door that locks, this would be considered exterior? The code seems silent on the matter.
 
That's how I look at it. The code would require exterior treated wood floor, exterior receptacles, and exterior siding, exterior door, exterior windows against the house too for this sunroom or porch too.
 
The only sunroom that does not require thermal isolation is a class V. I didn't think about the electrical outlets. Is the electrical code any clearer on what is deemed exterior?
 
To me "outdoors" means exterior.

E4002.8 Damp locations. A receptacle installed outdoors in
a location protected from the weather or in other damp locations
shall have an enclosure for the receptacle that is weatherproof
when the receptacle cover(s) is closed and an
attachment plug cap is not inserted. An installation suitable
for wet locations shall also be considered suitable for damp
locations. A receptacle shall be considered to be in a location
protected from the weather where located under roofed open
porches, canopies and similar structures and not subject to
rain or water runoff. Fifteen- and 20-ampere, 125- and 250-
volt nonlocking receptacles installed in damp locations shall
be listed a weather-resistant type. [406.9(A)]
 
The difference between interior and exterior in this context would be related to the exposure to rain/snow/ice, affecting safety.

We always looked at sunrooms as interior, even if they were unheated.
 
In R301.2.1.1.1 it states that a sunroom may be open, i.e., a covered porch.

In my case, the sunroom is completely enclosed with plastic film windows. There is one weather resistant outlet. The inspector wants us to build a landing to the sunroom which will take up a significant portion of the room. The door exiting the sunroom walks out flush to a patio. I have argued that this is the "exterior door".
 
https://www.nationalsunroom.org/AAMA-NSA-2100-19.pdf

I think I may have found the answer to my query if anyone is interested.

In R301.2.1.1.1 Sunrooms. Sunrooms shall comply with AAMA/NPEA/NSA 2100.

The following seems to be the only pertinent section:

1705000432981.png

I assume that this means Categories II thru V are considered indoor space. Therefore, no landing is necessary.

And, by the way. . .

1705000662239.png
 
We use the 2018 IRC for houses here which does not have the exception no matter if the sunroom is screened in or weather tight.

E3901.2 General purpose receptacle distribution. In every
kitchen, family room, dining room, living room, parlor,
library, den, sun room, bedroom, recreation room, or similar
room or area of dwelling units, receptacle outlets shall be
installed in accordance with the general provisions specified in
Sections E3901.2.1 through E3901.2.3 (see Figure E3901.2).

But we need to make sure that it is a sunroom, but I'm not sure if a sun room is the same as a sunroom:

[RB] SUNROOM. A one-story structure attached to a dwelling
with a glazing area in excess of 40 percent of the gross
area of the structure’s exterior walls and roof.
For the definition applicable in Chapter 11, see Section
N1101.6.

So if it has less than 40% glazing or no glazing at all it's not a sunroom.

(My dictionary says glazing is the act of installing windows????)

So how do you measure the glazing area? IRC says:

[RB] GLAZING AREA. The interior surface area of all
glazed fenestration, including the area of sash, curbing or
other framing elements, that enclose conditioned space.
Includes the area of glazed fenestration assemblies in walls
bounding conditioned basements.

So if the sunroom is not conditioned or not attached to a dwelling you can't add up the glass or plastic sq ft to see if it is over 40%. This means if it is not conditioned it can't be a sunroom even if it is all glass, so you don't need to space the receptables as a sun room per code.

Also this would mean a Category 1 sunroom is not a sunroom. Maybe it's a porch?

Porch in not defined in the IRC but my dictionary it says it's a covered shelter in front of a building. (Notice, not on the side or rear of a building)

IRC E3901.7 requires at least one receptacle on a porch not higher then 6'-6" above the porch surface. According to my dictionary a porch wall, roof, window, or windowsill is a surface.

I hope this makes it plan.
 
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To be clear, the electrical issue is not my concern. The stair landing is. I seem to have a unique talent for running head first into these apparent contradictions in the code. Obviously, the definition of sunroom in chapter 2 does not seem to agree with all the different categories in R301.2.1.1.1 Sunrooms. The separate categories exist because the code is applied differently to each. There is a chart in the commentary that outlines the differences.

In your opinion, do you think I need a stair landing at the top step of the stairs going from the dwelling to the sunroom when the sunroom is fully enclosed and weather tight as described for a category III sunroom? The inspector thinks I do. If the stairs are considered interior, I don't. Again, what is interior and what is exterior? I tend to agree with TMURRAY. The requirement for the landing should have to do with weather, i.e., ice on the steps or maybe just wet and slippery due to exposure to the outdoors. This seems to be the only explanation that makes any sense. The commentary is of course silent on the issue.
 
Energystar said:
In R301.2.1.1.1 it states that a sunroom may be open, i.e., a covered porch.

In my case, the sunroom is completely enclosed with plastic film windows. There is one weather resistant outlet. The inspector wants us to build a landing to the sunroom which will take up a significant portion of the room. The door exiting the sunroom walks out flush to a patio. I have argued that this is the "exterior door".
Click to expand...

That's for purposes of wind design, not for determining whether or not the sunroom space is interior or exterior.
 
I would say they it is an interior a stairway and no landing required.

I just wanted to see if the other inspectors here agree with me about the receptacle spacing and my interpretation on what a sunroom is and that the glazing can only be counted if the sunroom is conditioned. Category I, II, and III sunrooms cannot be defined as a sunroom per definition of "Glazing Area" because they are not conditioned.
But even if the room is not defined as a sunroom and is weather tight it still needs to have receptables per the E3901.2 6' and 12' rule even if it is not conditioned because it would be similar to a sunroom or sun room.

It's so great that the IRC makes this so easy to understand. Comments are encouraged.
 
I think we've sufficiently beat this topic to death. Thank's for the help. I have successfully convinced the inspector.
 
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