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Step from garage into House??

Andrew Bush

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I do not see anywhere in the IRC 2015 that requires a step from the garage into the house. I saw the opening penetrations R302.5 & Garage section R309. Is the step still a requirement and if so is there a minimum dimension?
 

cda

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Welcome

Give it a day for great responses.

Not into houses, I believe the answer is no.

I think the required slope takes care of it.
 

Glenn

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There is no requirement for a step between the garage and the house in any of the IRC editions. Bear in mind, however, that most government jurisdictions amend the codes before adopting. You should always double check your local code amendments.
 

classicT

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Not a code requirement, but is a practical requirement due to the different floor elevations.

If floor is framed on top of foundation, will typically have 2 steps. (1.5" mud sill, 9.5" floor joist, 3/4" deck = 11.75"+ threshold height)

If floor is dropped inside foundation, typically one step. (1.5" mud sill, 3/4" deck = 2.25" + threshold height)
 

ADAguy

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As noted above, "it depends" on type of foundation, slab or crawl. consider also that a level transition will accommodate a WC in the future. Be sure however that if a laundry is in the garage that the floor slopes to the driveway to allow for overflows.
 

Glenn

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As a fun little anecdote, I went into my vintage library, as there indeed is history of a step being required. Enjoy!

SBCCI (Southern Standard Building Code)
--1965, Section 506): "[a door] may be permitted provided the sill is raised at least 8 inches above the garage floor when the doorway connects directly with any room in which there is any direct-fired heating device or gas fixture."
--1994, Section 411.2.8: "Connection of an automobile parking garage with any room in which there is afuel-fired appliance shall be by means of a door way with a raised sill at least 8 inches above the garage floor or through a vestibule providing two door separation."

So the southern code was concerned with ignition of gasses. This is reflected in the current I-codes where fuel-burning appliances must have their ignition source at least 18" above the floor.

BOCA (National Building Code)
--1978, Section 413.1.1: "The sills of all door openings between the garage and dwelling shall be raised not less than four inches above the garage floor."
--1999, Section 407.5 "The sills of all door openings between private garages and adjacent interior spaces shall be raised not less than 4 inches above the garage floor"

There isn't really anything to glean from these BOCA provisions as to "why" they wanted the step in the BOCA code.

ICBO (Uniform Building Code)
--1927, Section 1505: "[attached garages shall] be equipped with fixed louvered or screened opening or exhaust ventilation with exhaust opening located within six inches of the floor."
--I don't have time right now to investigate my entire UBC collection for the evolution of this provision because I have every edition. It will take some time.

CABO (One and Two Family Dwelling Code)
--1986 was when this new provision was introduced, section 210.3 "That area of floor used for parking of automobiles or other vehicles shall be sloped to facilitate the movement of liquids toward the main vehicle entry doorway."

--So it seems back in the 20's the UBC concern was gas and they required venting to the exterior.
--Then in the 60's and 70's (maybe earlier but my SBCCI and BOCA collection doesn't go back further than 1965) they addressed the concern of gas with the step to the house, but referenced the need for a fuel-burning appliance to create the hazard of igniting the gasses.
--In modern codes there are two issues. Leaking fluid gasoline and other liquid contaminants that could drain to the house door and explosive gasses that can be ignited. This is now covered with the sloping floor requirement and the raised ignition source requirement.

Check out my youtube channel for short code history videos. I think I'll do one on this subject. This was pretty fun. Thanks for the motivation to research. I love these old books.
 

conarb

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JFYI, through the 50s and 60s we built to two standards, for most homes we built a monolithic pour for garages, for anyone who was getting a FHA loan we built a stem wall around the garage and recessed a slab later at least 6" below floor level. To this day I still put vents around the garage, a few years ago I had an inspector ask why I did that? Heaters, water heaters, and gas dryers were always raised up on platforms at least 18" above the garage floor.

On another subject but related, last week Berkeley passed an ordinance banning gas lines into all new buildings.

BTW, on homes built for FHA loans we had two inspections, local and Federal, I remember a retaining wall that passed local, then the FHA inspector made us tear it down and rebuild it, then the local inspector made us tear it down again and rebuild it his way.
 
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ICE

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BTW, on homes built for FHA loans we had two inspections, local and Federal, I remember a retaining wall that passed local, then the FHA inspector made us tear it down and rebuild it, then the local inspector made us tear it down again and rebuild it his way.

You should have sought out a lawyer.
 
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mtlogcabin

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Not under CABO and the legacy codes for dwelling units. 8 1/4" was the max for a riser and 9" minimum for the tread back in the early 80's. Our state amended the IRC and still allows it.
I believe it is crazy considering the number of slips and falls on stairs and considering how large homes are today then in the past. Do builders really need to build that way to create a little bit more usable space?

(9) Subsection R311.7.5.1, Risers, is amended to allow a maximum riser height of 8 1/4 inches.

(10) Subsection R311.7.5.2, Treads, is amended to allow a minimum tread depth of nine inches.
 

Glenn

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Not under CABO and the legacy codes for dwelling units. 8 1/4" was the max for a riser and 9" minimum for the tread back in the early 80's. Our state amended the IRC and still allows it.
I believe it is crazy considering the number of slips and falls on stairs and considering how large homes are today then in the past. Do builders really need to build that way to create a little bit more usable space?

(9) Subsection R311.7.5.1, Risers, is amended to allow a maximum riser height of 8 1/4 inches.

(10) Subsection R311.7.5.2, Treads, is amended to allow a minimum tread depth of nine inches.
I have a 1950's home. The basement stairs were steep and the headroom horrible. The stairs were also falling apart. Years ago when finishing the basement, I rebuilt the stairs. Both the rise/run and headroom didn't meet current code. I was the only tall one in the house (my boys are catching up though). So I made the decision that steep stairs was a hazard for everyone, where headroom was only for tall folks. I rebuilt to 7.75/10 and really messed up the headroom. My oldest son is now 15 and recently hit his head for the first time. I laughed and welcomed him to the world he better get used to. However, I knew then a kitchen remodel was in my future and when that happens I plan to remove part of the floor to open up the stairway and fix the headroom. Haven't gotten there yet, but that's the plan. I'm 19 years into my long-term plan with this home.

Every cycle there is a proposal to the IRC to make it 7/11 like the IBC. What comes up in opposition is the reality that many states amend the IRC to allow more steep stairs.
 

Paul Sweet

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Not everybody wants or can afford a McMansion. Less expensive homes & townhouses are still being built in the 1000 - 1500 SF range, and there isn't room in them for stairs less steep than 8 1/4 R & 9" T.
 
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