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Deck Stairs Landing

G

Gabriel Gaul

REGISTERED
Joined
Jul 15, 2020
Messages
1
Location
Manhattan, KS
Long story short, I've been butting heads a lot recently with my local building enforcement officials. In my most recent permit application for a deck I'm getting ready to build, he came back that I needed a 12" thick slab for the landing my deck stairs will terminate on. I'm rebuilding a deck that was removed in the exact same footprint. It is above an existing concrete patio. Stairs are going to be a split landing and the final run of 5 feet will land on the existing patio. This is exactly the same as the old deck.

I'm trying to find in the building code where this is a requirement but failing hard.

Do I really need to rent a concrete saw and saw out a section of the old patio and re pour to make these people happy?

As of Jan 1 we moved to the 2018 Code. I went to all the code "changes" meetings and this was never addressed.
 
Welcome

So are you landing Air Force one on this twelve inch slab???

Ask the nice inspector for the code reference they are citing,

They are supposed to do that!!

If they ever come up with one, research it and also post it here.
 
I concur with CDA, but without knowing how your local AHJ adopted the 2018 IRC and what possible modifications, I would note anything is possible.

However, that requirement is not in the 2018 Model IRC that I am aware of.

I am sure Glenn will chime in with more detail,

but simply asking very nicely the code official for the code section that requires this specific detail to educate yourself, and just very nicely say, this is the first time I have ever encountered this requirement and I have other projects going on and that I am concerned about this for inspections in other jurisdictions, as we have not included this rework in our project and I need to talk with the client as it adds a significant cost.

Without a specific code section I would say you have a strong case for not doing it.
 
Is 12" your frost depth? They could be interpreting the code that the stairs need a "foundation". We've never taken this approach with stair stringers, but others have.
 
I worked for a few inspection companies and they all had different policies about this from 4" concrete to a 36" frost depth. I try to stay consistent with the other inspectors in my company.

This is from 2015 IRC:

R403.1.4 Minimum depth. Exterior footings shall be
placed not less than 12 inches (305 mm) below the undisturbed
ground surface. Where applicable, the depth of footings
shall also conform to Sections R403.1.4.1 through
R403.1.4.2.
R403.1.4.1 Frost protection. Except where otherwise
protected from frost, foundation walls, piers and other
permanent supports of buildings and structures shall be
protected from frost by one or more of the following
methods:
1. Extended below the frost line specified in Table
R301.2.(1).
2. Constructed in accordance with Section R403.3.
3. Constructed in accordance with ASCE 32.
4. Erected on solid rock.
Exceptions:
1. Protection of freestanding accessory structures
with an area of 600 square feet (56 m2) or less,
of light-frame construction, with an eave
height of 10 feet (3048 mm) or less shall not be
required.
2. Protection of freestanding accessory structures
with an area of 400 square feet (37 m2)
or less, of other than light-frame construction,
with an eave height of 10 feet (3048 mm) or
less shall not be required.
3. Decks not supported by a dwelling need not be
provided with footings that extend below the
frost line.
Footings shall not bear on frozen soil unless the frozen
condition is permanent.

But to make it more more confusing the code only says walls are to be supported on footings:

R403.1 General. All exterior walls shall be supported on
continuous solid or fully grouted masonry or concrete footings,
crushed stone footings, wood foundations, or other
approved structural systems which shall be of sufficient
design to accommodate all loads according to Section R301
and to transmit the resulting loads to the soil within the limitations
as determined from the character of the soil. Footings
shall be supported on undisturbed natural soils or engineered
fill. Concrete footing shall be designed and constructed in
accordance with the provisions of Section R403 or in accordance
with ACI 332.
 
Gabriel Gaul said:
Long story short, I've been butting heads a lot recently with my local building enforcement officials. In my most recent permit application for a deck I'm getting ready to build, he came back that I needed a 12" thick slab for the landing my deck stairs will terminate on. I'm rebuilding a deck that was removed in the exact same footprint. It is above an existing concrete patio. Stairs are going to be a split landing and the final run of 5 feet will land on the existing patio. This is exactly the same as the old deck.

I'm trying to find in the building code where this is a requirement but failing hard.

Do I really need to rent a concrete saw and saw out a section of the old patio and re pour to make these people happy?

As of Jan 1 we moved to the 2018 Code. I went to all the code "changes" meetings and this was never addressed.
Click to expand...

I apologize to you, Gabriel, on behalf of the code profession for what you are experiencing. It is absurd and inappropriate. It's a great way to alienate you from ever involving your building department in future work. It is likely the sad result of ignorance and a lack of confidence to make professional judgement on behalf of your building official.

A "book reader" could find a way to require this through ink on paper, and for that, I am sorry. A professional would not require this through legitimate knowledge and experience.

As quoted in previous replies, stairs are a structure and a structure has to transmit all loads to the earth. This is typically done with a foundation system.

Stairs are the weirdo. They are the square that does not fit the round hole unless hammered with authority (building official). For most deck code questions, I've likely written an article about it over the last 14 years. This article is specific to your question and I bring up another important point about rise uniformity.

Let me know if you have any follow up questions. I suggest being as diplomatic and friendly as possible as you try to discuss this with your BO. Basically... don't use the words I used here to describe the situation...

https://www.deckmagazine.com/design-construction/railings/deck-stairs-on-frost-footings_o
 
So you are from KC? Any snow or frost there?
Expose the edge of the patio to determine its thickness and start from there.
The stair must be attached to a surface that will not move due to frost heaves.
 
Well, I suppose it had to happen. I've always done my best to be a common sense building inspector - now building official. But now it seems I'm being called out for being unreasonable. I am the B.O. Gabriel is referring to. :)

As indicated by the above conversation, there are differing opinions on this issue. And there's also some missing info.

Gabriel - the one thing that should have been relayed to you by our plan review team is this: if the existing slab is in good condition, you can absolutely go back with the stringers bearing on the slab. No need to saw cut a perfectly good piece of concrete!

The 12" thickened slab (under the stringer bearing point only) is a compromise our staff came up with a number of years ago, to NOT have to require frost depth footings, on new construction.

I'd be more than willing to discuss this with you! Give me a call when you can.
 
Darren Emery said:
Well, I suppose it had to happen. I've always done my best to be a common sense building inspector - now building official. But now it seems I'm being called out for being unreasonable. I am the B.O. Gabriel is referring to. :)

As indicated by the above conversation, there are differing opinions on this issue. And there's also some missing info.

Gabriel - the one thing that should have been relayed to you by our plan review team is this: if the existing slab is in good condition, you can absolutely go back with the stringers bearing on the slab. No need to saw cut a perfectly good piece of concrete!

The 12" thickened slab (under the stringer bearing point only) is a compromise our staff came up with a number of years ago, to NOT have to require frost depth footings, on new construction.

I'd be more than willing to discuss this with you! Give me a call when you can.
Click to expand...


Well bless your heart!!!

There is always three sides to a code question.

Still was wondering if the 12 inches was for air force one to land on
 
Darren Emery said:
Well, I suppose it had to happen. I've always done my best to be a common sense building inspector - now building official. But now it seems I'm being called out for being unreasonable. I am the B.O. Gabriel is referring to. :)

As indicated by the above conversation, there are differing opinions on this issue. And there's also some missing info.

Gabriel - the one thing that should have been relayed to you by our plan review team is this: if the existing slab is in good condition, you can absolutely go back with the stringers bearing on the slab. No need to saw cut a perfectly good piece of concrete!

The 12" thickened slab (under the stringer bearing point only) is a compromise our staff came up with a number of years ago, to NOT have to require frost depth footings, on new construction.

I'd be more than willing to discuss this with you! Give me a call when you can.
Click to expand...
What a professional response and pleasant exchange.

In looking this thread over, I wish mine was as such. My apologies, Darren, for so easily passing out stereotypes as the conclusion. On the internet, I was complaining about a persona, not a person. I am clearly becoming bias to all the bad stories I receive asking for help.
 
Here is the dumb requirement in CT:

4. The footing for the grade level termination of stairs or ramps attached to decks or landings,
whether the deck or landing is supported by a dwelling or not, shall only be required to be
placed at least 12 inches (305 mm) below the undisturbed ground surface in accordance
with R403.1.4.

Not sure where the State got it from (I assumed newer I-code or DCA6), but yes, I now have to make people pour a 12" thick pad at the bottom of the stairs....It lives here in our code:

(Amd) R403.1.4.1 Frost protection.
 
Common sense is not too common, I to wonder about some things and what is required.

As a BO I have not enforced a pad at the bottom of the stairs for a deck. Precast stairs system have been supported on angle iron on the house and cement blocks a the front so why should we require a bigfooting to go below frost which is 48 inches here when a PT plate at the heal of the stringer is fine because the 4 or 12-inch slab is going jump up and down as much as the stair.

DCA6 2015 edition has this detail

upload_2020-7-16_19-13-21.png
 
Please provide the IRC code that requires a concrete pad at the bottom of a deck stairway?

The DCA figure 34 is for stair footings.
IRC2012 R507 Decks; no requirement.
 
Gabriel Gaul said:
Long story short, I've been butting heads a lot recently with my local building enforcement officials.
.
Click to expand...
Gabe ... did you get the information or explanation that you needed? There has been a lot of good info here, some good explanations of what they are asking for and why.
 
Yep, wasn't trying to get him revved up...lol. Just agreeing to the not so common sense. Then apparently i wasn't listening correctly.:confused:
He must have been think of some one else.

The 250R was my favorite Bike and 11 was my number back in my younger years racing dirt bikes and quads. Been using the handle for over 30 years.:D
 
What I would want to know is the thickness and reinforcing of the existing slab and how much gravel is below it and if the site is well drained. To me for such a light loading gravel and drainage would be more important than slab thickness.
 
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