# Wall Height vs Story Height



## Civility (Jul 12, 2018)

Hi to All - 

I'm planning a small outbuilding, less than 200sf, so in my county (Maui, HI) a permit is not required if there is no water or electricity involved. But I will be building another, permitted structure later, so I don't want any raised eyebrows when they see my "shed". Also I might want to retro permit it later for said water and power, so I want it to be legit. 

I'm looking at a simple gable roof, open on the inside (no ceiling), with a mezzanine/loft. The IRC (R301.3.1) allows a story height of 11'7", with an extra 8' height at the gable end wall. My ceiling height under the loft will be 8', but the loft will be open to the rest of the structure, so for most of the room the ceiling height will vary from 8' at the side wall to around 16' under the ridge.

Questions: 
1. Is the story height determined at the wall (haha I wish), or is it taken as the maximum height anywhere in the room?

2. If a permit problem ever happened, I could get the story height into legal range by extending the loft all the way across the room, with an opening into the resulting attic space. How large an opening could I have into the attic - and where is the line between an attic and a mezzanine?

3. R301.3.1 "Story Height" says that an additional 8' bearing wall clear height is permitted for gable end walls, and this is the confusing part. The section is about story height, and now we are given a maximum for wall height? Or does this mean that a structure with gable ends can have a larger story height, as determined by the gable wall height?

Any light you can shed on this would be helpful...

Thanks a lot -
David

BTW - nice place you've got here!


----------



## cda (Jul 12, 2018)

Welcome!!

I think I need an on site visit, to give you a good answer


----------



## cda (Jul 12, 2018)

Give it a little time and you will get some great answers


----------



## ADAguy (Jul 18, 2018)

Aloha,
Is that photo really you at 65 (smiling)?
Is shed to have a foundation? On lava or soil? Crawl  or slab?
Is it a pre-built or are you building it?


----------



## Civility (Jul 18, 2018)

ADAguy - 

Thanks - 

Foundation is post and beam - 2' crawl space. On soil - former pineapple field.
I am designing/building it.

Well, the photo was unintentional - not sure where they got that from. Taken a few years ago...


----------



## Paul Sweet (Jul 18, 2018)

The limits in R301.3.1 are for using the prescriptive design tables in the IRC.  Engineered design is required once you exceed them.

R301.3.1 refers to Table R602.3(5), which allows non-bearing walls to be 14 ft. high for 2x4 studs, and 20 ft. for 2x6 studs.

A gable end wall is typically non-bearing.  However, if the loft doesn't extend the full length of the building then the ridge acts as a beam, and the column supporting it needs to be sized based on the full height to the ridge.


----------

