stair design for an exterior door

[RustyShackleford]

I am building a 12x12 ft deck off the back of my house. I want it to be simple and clean - specifcally, no railing. If 30" or less above grade, no railing is required; however, a staircase with 3 or fewer risers does not require a rail, so the deck will actually be somewhere in the 22.5-24" above grade. All fine and good. But this means I need to drop somewhere in the 12" range from the French doors to the main deck.

At first I thought to do this with two steps of only 6" rise or so (using the usual formulae for what run goes best with a certain rise). So there'd be one tread just outside the doors, and another between that one and the deck. But I also read that for decks it's wise to have a slight drop from door threshold to deck, maybe 2-3", so water can't flow into the door, and leaves and debris tend to stay out. So I thought that first tread should be a few inches below the threshold. Building inspector (the helpful kind, not the dick kind) said that less than 2" tends to be accident prone and 4" or more is considered a "step" (so I run into the thing where having one odd-sized step is illegal and dangerous); he suggested making that drop be exactly 2".

However, I'm wondering if it'd make sense to just have the first step be RIGHT outside the door - so there's only one tread, and it is 6" below the threshold. Of course, that might be kinda awkward. But it gets around the problem that, in the first proposal, the rise from the top tread to the threshold would be less than the two risers from the deck up to the tread right outside the door.

BTW, since this isn't the main egress door, the usual code requirement, to have a 30"-wide landing outside the door, does not apply.

Also, this chart is interesting:

(broken link removed to http://www.fas.harvard.edu/~loebinfo/loebinfo/Proportions/stairsdoors.html)

... and suggests, if I go with the first proposal, that the drop from threshold should only be 1.5" or so - to keep the angle of that top step at 7.5 degrees or less.

 

[semipro]

Have you considered a two tiered deck? Maybe 12' x 12' is not big enough for that.
Otherwise maybe you could drop the deck height another 2 inches and then do the two 6" steps you mention.

 

[ironpony]

A single step out side a door is tricky, you will get used to it company will not = people tripping. I would only do it if I could have a 18-24 inch landing outside the door. Then I would go with splitting the 12 inch into 6 " rises one tread.

 

[RustyShackleford]

Guys, thanks for responding, but I am not understanding your suggestions ...

Ironpony, do you mean this 18-24" landing would be at or slightly below threshold level, or 6" below it ?

Semipro, yeah I don't think two-tiered would work. As far as dropping the deck 2", I don't see how that helps. I still need to get down 12" or so from the threshold to the deck. The main question is what is right outside the door ?
1. Something level with inside floor. Problem of water and debris getting into house more easily.
2. Something 2" or so below threshold. Problem that it's not-uniform with the two 6" or so steps below it.
3. Something 6" below threshold. Problem is that having step RIGHT outside the door is awkward.

 

[ironpony]

6 inch below so you can stay within you riser spec. think about your front door you probably step down as you exit....................just would want more than a 12 inch tread to hit

 

[ironpony]

trying to think outside the box here..................... raise the deck 4.5 inches so you have a 7.5 inch step going into the house.
use (3) 7.5-8 inch risers to get up onto the deck, regrade dirt at base of steps to get added height
deck less than 30 inches above grade and only 3 risers..................
no railings

 

[RustyShackleford]

... raise the deck 4.5 inches so you have a 7.5 inch step going into the house.
use (3) 7.5-8 inch risers to get up onto the deck, regrade dirt at base of steps to get added height
deck less than 30 inches above grade and only 3 risers..................

Right, if I could get the grade within 32" (vertical) of door threshold - so four 8" risers, three on steps to grade, one coming into door - I'd be set. Problem is, I don't think I can raise the grade that much without messing up the drainage around the house. But the first step (no pun intended !!) is to get some fill dirt and play with that. But I don't think it'll work.

 

[RustyShackleford]

6 inch below so you can stay within you riser spec. think about your front door you probably step down as you exit....................just would want more than a 12 inch tread to hit

Gotcha, so just have one tread, 6" below threshold and 6" above deck. But make it pretty wide. But it can't be more than 15" or so, or the "slope" is less than 20 degrees, so the "accident-prone zone" in that cool chart I linked in OP. I should maybe try to dummy it up and see how it feels - kinda outside the bounds of the rise+run=17" rule-of-thumb, but close to the 2*rise+run=25" one.

 

[ironpony]

I would agree about the slope issue if it were multiple steps, this would fall more into a landing.

 

[SmokeyTheBear]

Rusty,

I suggest that you get a copy of the building code in effect where you are putting the deck and steps, something spouted by Harvard's theatrical production website isn't going to necessarily apply where you are and in fact may place you in violation of the local codes.

You have to keep the locals happy.

This is true of even things like the current IBC (International Building Code) or IRC (International Residential Code) requirements, they don't pass all localities. In particular some fasteners are too small to meet a lot of local building codes.

 

[RustyShackleford]

Thanks Smokey, I have perused the NC building code extensively. It's not really terribly restrictive - just wants risers 8-1/4" minimum and treads 9" minimum, and some stuff about odd-sized rises and runs, but which doesn't really apply here. And some stuff about landings, most of which is excused if it isn't the "required egress door". IOW, the "locals" will be happy for sure, just want to make sure *I* am.

I'm really thinking Ironpony's notion of only one tread, about 6" below the threshold and above the deck, and more than 12" wide, is the way to go. I was a little concerned about stepping down straight out of the door, but the code allows up to 8" even for the required egress door. Of course that's a 36" "in the direction of travel"landing, but a landing isn't required for other exterior doors.

The relevant code text is here:

 

[jebatty]

The deck I built used many of the suggestions given above. It was a two-tiered deck, and the step onto the deck from the house was about 2" below the door threshold. We didn't want a railing on the deck, code required a railing if the deck was more than 2 feet above grade, so we added fill as needed to bring the ground level up to within 2 feet of the deck. The inspector said we needed a railing, I brought out the tape measure and showed the distance was less than 2 feet, and the inspector walked away in a huff.

 

[mywaynow]

What kind of door is entering the house off the deck? A sliding door creates a different scenario than a hinged door. I would keep the surface at least 2 inches below the threshold or you will invite water into the house. A pair of 2x12s as the first step/landing then a standard step hieght onto the deck. What ever happens with the landing to grade level, offset it with a cement landing that meets the tread at the proper hieght. Don't vary step hieghts unless you want to see people falling.

 

[SmokeyTheBear]

Thanks Smokey, I have perused the NC building code extensively. It's not really terribly restrictive - just wants risers 8-1/4" minimum and treads 9" minimum, and some stuff about odd-sized rises and runs, but which doesn't really apply here. And some stuff about landings, most of which is excused if it isn't the "required egress door". IOW, the "locals" will be happy for sure, just want to make sure *I* am.

I'm really thinking Ironpony's notion of only one tread, about 6" below the threshold and above the deck, and more than 12" wide, is the way to go. I was a little concerned about stepping down straight out of the door, but the code allows up to 8" even for the required egress door. Of course that's a 36" "in the direction of travel"landing, but a landing isn't required for other exterior doors.

The relevant code text is here:
View attachment 108134

If NC has any kind of home rule provision you need to talk to the town you are building in or perhaps the county..

I built a deck last year and have a uniform rise from the ground to the deck and the same rise from the deck to the entry door. No surprises for old folks like me .

Just be careful in what code you read it must be that that the town requires you to follow, if they don't have oe then what the county requires, and if the county doesn't one then what the state requires the order from most restrictive goes from the town through the county to least restrictive at the state level.

 

[save$]

I hope you construct the deck and steps so that you can add rails. You won't get the same surface use from a 12 x 12 deck without a rails as you would with. Just consider chair placement. Steps without rails are sinister. Not just us old folks like them, the young ones like them too. If you ever get snow or ice on your steps and no rail, I wouldn't dare use them.

 

[RustyShackleford]

Thanks again, everyone, for all the great ideas !

I built a deck last year and have a uniform rise from the ground to the deck and the same rise from the deck to the entry door. No surprises for old folks like me .

I wondered about that. But a person will have to walk across about 8-10ft of flat deck between coming up to the deck from grade, and coming inside from the deck. I don't THINK muscle memory of the one rise will be a problem on the other.

Just be careful in what code you read it must be that that the town requires you to follow, if they don't have oe then what the county requires, and if the county doesn't one then what the state requires the order from most restrictive goes from the town through the county to least restrictive at the state level.

I'm good, really, but thanks for your continued concern. I do not live in a town, and my county just uses the North Carolina code.

... the step onto the deck from the house was about 2" below the door threshold.

I'm starting to lean back towards the plan of two treads, one 2" below threshold, one 6" below that and 6" above deck. I realized the threshold itself is about 1" above inside floor, so 2" below that is only 1" below inside floor. So I think my concern about two 6" risers followed by a 1" rise is not an issue. But I'm still intrigued by the idea of a single tread, for example it will waste less deck space, and if I make it very wide, almost a landing, as Ironpony suggests, it may be fine. I need to mock it up somehow.

the inspector walked away in a huff.

I'm not sure what's up with inspectors acting like dickheads. I have had nothing but good relations with the inspectors - they don't give me a hard time about minutae, they sign off on stuff that isn't quite done, and they give helpful advice not directly related to code compliance - and I am in one of the more heavily regulated counties in NC. I attribute it to several things. Maybe most importantly, the builder and homeowner are the same person - me, so they know I'm not some shady builder trying to cut costs as much as possible, and additionally, I suspect I give the impression of a person who likes to do things the right way. Secondly, the friend helping me is an experienced carpenter who grew up working with his father, who has been building houses for 40 years; their family company does first-class work and the inspectors probably know it. Still I hear about people elsewhere having so much grief; some people just can't handle having a little power, I guess.

What kind of door is entering the house off the deck?

In-swing French doors. With out-swing screen doors.

I hope you construct the deck and steps so that you can add rails. ... Steps without rails are sinister. ...If you ever get snow or ice on your steps and no rail, I wouldn't dare use them.

Sure, I could add them. But I'm not too worried. If I were pushing to 30" deck-to-grade drop it'd be one thing, but I'm looking at 24" or a little less. And this isn't my main ingress/egress, so I probably just won't go there in bad weather. Plus, snow and ice, here ? You gotta be kidding. I do kinda remember snow a decade or so back ...