U shaped stair layout?

[shad]

I'm in the planning stages of building the timber framed house in Jack Sobon's book. I`m stuck trying to figure how to lay out the U shaped winder staircase called for in the plans.  The stairwell opening is 8x5 and the floor height is 108 inches.  On a u-shaped stairway, how do you figure the run?  And how long can the treads be?  Is there any good software for stair layout?  Thanks for any information you can share.  Here's a picture from the book of what I'm working on doing.   

[shinnlinger]

Shad,
Is the 108" finished floor to finished floor?  I ussually ignore the U factor in the intial figure of riser height and would divide 108 by 7.5 and that works out 14.4 which I fiddled with to make 15 steps with a rise of 7 and 7-32nds for your rise of each step. You could do 14 steps if you had too but the rise is about 7-3/4, and you might need to meet code.  Code might not like 7-7/32nds either and make you run 16 steps

Now you need to figure where you can stick your steps. I would shoot for a tread in the 12" area (again, check code) but you need about 15 feet of stair run.  If space is tight, You can drop the riser and start your descent right at the top of the stairs, but most people run the top step even with the top floor.  You can also put two steps on the U platfrom and maybe even 4 if you run tapered treads, but I caution against this even if your building codes allow it as they can be trip hazards.

But anyways I figure where I want the U platform to be and set that and then build the bottom set of risers to the U and then upper set to the upper floor.  Remember to deduct the tread thickness and chop it off the bottom of the first set of risers and keep at least a 6'8" head clearance height.

[Raphael]

I went with 14 risers and 13 (actually ~13.5) treads.
Best bet may be to just draw it out in plan view to figure (fiddle) out a best fit for the 13 or 14 treads you'll need.

[Jasperfield]

Additionally, you may be required to have 3'-4' of clear floor space and clear head room at the top and bottom landings.

Make the stairs wide enough to move furniture between the attached stair rails.

I'll say this. Stair placement and design can be the most time consuming of all architectural tasks. As you get older, you're going to want a longer tread and a shorter rise.

[Hilltop366]

To make a set of stairs I always try to use the 25 rule, where the rise x 2 + run = 25 it always seem to feel right when climbing them, trying not to go over 7.5 rise or a little less might be better.

Eg. rise of 7.5 x 2 = 15 this would leave 10 for the run to = 25
or if landscaping with 6'" (5.5") ties , 5.5 x 2 = 11 + 14" run = 25

hope this helps.

[shad]

Thanks for all the info. Yes the finished floor to finished floor height is 108" and the well hole in the second floor is 8'x5'. We posted a drawing from the book above to give you an idea of what I'm wanting to do. I like the way it has 3 steps and then a half landing on all three levels.  The main problem I'm having is figuring out how long I can make each tread and have it all still fit in the 8'x5' area. I'll try drawing it to scale and cutting it out in cardboard tomorrow.

[shinnlinger]

SHad,
Do you need to meet any code?

I don't think they will like the half steps unless they are at least 6-8 inches at the narrow end, but that can vary so I would start with that department.  Even if you don't have that issue, you don't want to turn an ankle on it either so I would stick with that measurement.  I would try to go with at least a 40 inch wide step if possible, you will want it when hauling the kingsize bed up.

Code might have something to say about a railing also, but try to make it removable.

A trick for tread depth is you can cut a 9 or 9.5 inch run on your risers but stick a 10 inch tread on it.  They  all hang out evenly over your toe kick so no one is the wiser and you get a more compact stair.

[jdtuttle]

Shad,
Stairs can be tricky. I can tell you how I do them. Divide 108 by 14 risers = 7.714 tread height ( about 7 13/16") Code requires between 6" & 8" riser height in NY.
Determine the distance from the top of your landing to the winder. Minimum finished tread width is 9". Your in a confined space so start with the minimum width. 7 risers X 8" = 56" that's the distance from the top to the landing. Ok here is where it can be confusing. 7 treads = 8 risers to the top or 8x 7.714 =  61.712     subtract that from the total height & you get the top of the winder height. 108"-61.712=46.228" Now subtract one tread height 46.228"-7.714"=38.574. that is the height of the deck you build the winder on. Now all you have to do is add the lower stairs. 4 treads at 8" will project 32".
One of the most common mistakes while building stairs is not allowing for tread thickness. You need to determine the tread thickness and remove that amount from the bottom of the stringer. You can have 9 1/2" treads.
The winder on the narrow side has to be a minimum of 7" at the narrowest point.
jim

[Hilltop366]

The hole in the second floor is 8' x 5' but you can put a step or two at the first floor out side of the opening if there is room, just be carefull to meet the requirements (personal & code) for overhead clearence.
it will be eaiser to figure once you deside on a total width for the stair case so you know how much to allow for the winder part, then starting at the top (because it is a fixed point) figure how many steps will fit between the landing and the winder the adjust the winder height to fit and work your way down. try it out by drawing it on the wall or cutting a test out of scrap.

[Jim_Rogers]

I have some information in pdf format about stair layout and code but the file is too large to post here even zipped.
If you'd like a copy, send me an email via regular email and I'll email you the zipped pdf.
I don't know if I can find the download site and post a link to that location or not. But if you can't accept the zipped file by email then let me know and I'll try and find it off the document and post it.

Jim Rogers

[Jim_Rogers]

To all, and especially Shad:

Yesterday, while on a tool selling trip to the western side of my state, I stopped by Jack Sobon's office and had a short chat with him about the stairs in the house he designed for the book.

First he said that the stairs will have to meet the code in force at the location of the house, and advised me to inform you to search out the code for your area and get that code and make sure your stair design complies with that code.

We reviewed the code for MA as we both live in this state. And the stairs in his book still meet the current code for MA.

He also explained that the code calls for a width of the stair way of 36" above the handrail, and that the handrail height should be 34" above the stair thread. This means that the stair threads can be less than 36" in length, but that usually everyone makes the stair thread the same length as the stair way width, but they don't have to be, if the lengths comply with code, for that location. I think we found that the minimum stair thread length has to be, in MA, no less than 31".

This can gain you some inches in order for your stair threads to fit into the space in the frame.

He asked me if you're going to have a stairway to the basement under the stairs going from the first floor to second floor. As he had designed his stairway layout so that in the house in the book would have a set of stairs to their basement. Because of this basement stairway the stairway going to the upper floor was moved over a bit. If you're not going to have a stairway under your stairs going to the second floor you may be able to move things a bit to get them into the size of the opening found in his book.

Jim Rogers

[shad]

Wow, Jim you really go that extra mile to help someone when they need it. Thanks for the great info. We just got back from our trip to Tennessee. Maybe now I can get back on track with the house plan.
We don't plan to have a basement, so we can move the stairs around a little.
Shad   

[Jim_Rogers]

Shad:
As much as it is information for you, it is a learning conversation for me.

Every time I stop by and talk with him, I learn something new.

He also placed an order for some tools, so it was a great visit......

Jim Rogers

[moonhill]

Interesting, Jim.  May I ask what sort of tools he was looking for?

Tim

[Jim_Rogers]

You know I thought Jack would have every kind of timber framing tool made, and he probably does, but he wanted more of the same.

He is asking for some specific older timber framing tools for the upcoming workshop this Fall.

The are called "shell augers".

He did provide me with some samples, for me to photograph, and I have found a couple so far.
But he wants me to find more for the class.

Jim Rogers

[buffhale]

Shad,
Stairs with 7.5 inch tread heights would be considered steep.  On the custom homes I have built in the past 7.25 was the maximum we would allow.  Treads were always 11.25 wide with a 1/2 to 3/4 inch overhang of the riser.  I have carpenters knees and must have a stair rail to ascend and descend most stairs.   I am 60 with low cartilage in my knees and my new shop stairs riser height is 5.5 inches.  This height is one I can manage up and down with out using a hand rail, I really like this riser height for comfort. This has a 11.25 tread with no overhang and an open riser.  It is very flat and falling would not likely be down the flight but just down on a tread. This lower riser height requires a much longer run which can be planned for.  With triangular landings the falling hazard for the elderly and very young is very great.  Good luck.   

[moonhill]

Maybe I will get a chance to use one this fall, the shell augers. 

Tim

[Raphael]

I just got a notice from Heartwood School (www.heartwoodschool.com).

"Our new Stairbuilding course is valuable for pros and owner-builders alike, and will be offered from October 5 - 9, 2009, the height of fall foliage season in the beautiful Berkshire Hills of western Massachusetts."

[Piston]

.....for the upcoming workshop this Fall.

Jim,
Which workshop is that?  Is it the stairbuilding one that Raphael just posted about?  Thanks.

[Jim_Rogers]

.....for the upcoming workshop this Fall.

Jim,
Which workshop is that?  Is it the stairbuilding one that Raphael just posted about?  Thanks.

No, a special workshop being held just before the eastern conference. The roster has been full and sold out for weeks.

Here is a link to the details:

http://www.tfguild.org/workshops/geodesign.html

This should be an interesting event......

[shinnlinger]

Shad, Here is what I did in a similar situation.  I hung the stringers off of 2x4s so I could begin dropping the stairs sooner in a tighter space and can insert my trim boards later without scribing....

[Rig]

I've built those exact stairs in my sister's house I modeled off of Sobon's house pictured above.

The easiest way to start any stair project is to draw them out with on the wall where the treads and risers will be touching them. Everything else falls into place for me once I have some lines drawn with a level and my framing square.

I love Jack's work and philosophy and I consider him my most influential mentor.

[Thomas-in-Kentucky]

Lots of good advice here.  I might add that I think anyone who leaves less than 6 feet by 8 feet for a U-shaped stairwell in a timberframe house is setting themselves up for trouble.  (6x10 is a lot more appropriate) Two years after I made the 6x8 decision, I had to build a set of stairs to fit.. and it was tight.  My rise worked out to be 7.5 to 7.75" and my run was 10", with 11" treads or so.  I don't think you'd want anything steeper than this, unless it's to reach an infrequently visited space. 

I put a landing midway in each of my two flights, and found it necessary to put a step in the landing going from the 1st to 2nd floor (the ceilings are taller than the 2nd to 3rd floor).  Anyway, in the dark, running down the stairs, I once forget which floor I was on and missed the step in the landing.  Ouch.  Probably a bad idea (OK, three bad ideas - running on stairs, in the dark, with a different design for each floor). 

Did I mention, we had to take the (temporary) handrails off recently to get a washing machine up to the second floor?  Now, try imagining a box spring mattress going up these stairs.  Glad we have a loft space - several items (like 4x8 sheets of drywall) have gone up over the balcony-railing, since they didn't fit up the stairs.