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framing rough opening for staircase

pkeena's picture

I am building my woodshop and I am putting in a full basement.  My question is how do I figure the rough opening for the staircase? 

(post #53902, reply #1 of 9)

Do an elevation drawing to scale of the stairs. Start with distance finished floor to finished floor, then add the upper floor framing. use calculator to figure rise and run. Get as close to 7/10 as you can. then draw it up. now you have to draw a vertical line at the point where you will have a minimum of 6'8" at the edge of a tread, remembering that the treads will overhang your drawn frame by wwhat? 2" or thereabouts and that the finished ceiling will rob some space. That line indicates the smallest that you can use for length of rough openning. Width will vary by what you have available from floorplan upstairs but for a shop, I'd recommend making it as wide as possible and consider how you will be able to get long lumber in as well as tools. a 1x12x14' won't turn corners very well.


Excellence is its own reward!

 

 

Oh Well,

We did the best we could...

(post #53902, reply #2 of 9)

If your wondering about the minimum length of the opening. You need to make sure the height between the front header and the closest tread is at least 6'-8". You might want to go more if you are going to be moving  stuff down the stairs.


      *Don't forget to acount for the Joist width and any sheetrock thickness.Also it might depend on where you are mounting you stringer. Flush or below the floor level.


After you know your total rise and run, you can subtract the 6'-8" from the total rise. The difference will be divided by each riser height. That will be the tread you have to worry about.  Then subtract the # of treads you came up from the floor, from the  the total # of treads. Multiply this #. by the tread run number. That will give you the total length of your opening. Go another foot if you can. that 6'- 8" is the key. I have gone less in certain situations by permission. 

Where there's A wheel there's a way, got any wheels?

(post #53902, reply #3 of 9)

I've built a few stairs and when it's a little complex or if the space is really tight or if I just feel like it, I'll make a story pole to mark off the rises and with a plumb bob, or level, mark out a work line on the lower floor. 


 


Then draw out the runs on the floor. You can then move the story pole along the treads you've drawn and identify the point where your headroom meets the corresponding riser on the pole.


 

 

(post #53902, reply #4 of 9)

I always figure about 10' for the rough opening. More is better if you have the space. Same with wider - go for 4' wide if you plan to use it to move stuff up and down.

If you have a deep floor sustem, you may need more length too.


I feel like I'm diagonally parked in a parallel universe.

(post #53902, reply #5 of 9)

http://forums.taunton.com/tp-breaktime/messages/?msg=21331.13  Here is one for the Paralell and perpenduliarly challenged. I'd like to hear what you all think. I have a feeling there is an easy way to do this. I just never did it. Anyone here dun it?

Where there's A wheel there's a way, got any wheels?

(post #53902, reply #6 of 9)

Boss,

There you go, giving away all those trade secrets and making it look easy!

;>)

Excellence is its own reward!

 

 

Oh Well,

We did the best we could...

(post #53902, reply #7 of 9)

Take the total height and divide by 7 . That will give you the number of risers. For example the total rise is 108". divided by 7 the answer is 15 with a remainder of 3. This gives you the number of risers 15 and the number of thread 14, (there is one less thread than risers because you begin with a riser and end with a riser).


Next take the number of risers, in this case 15, and divide into the remainder from above. 15 divided into 3 that will equal .2. Add that to the 7" . This means that each riser will be 7.2"


Thread width is determined by the architech, or in your case by the amount of space you wish to attribute to each thread. 14 thread at 10" equals for example  11' 9". If you wish to use a 2X12 allow11 1/4" per thread.


Charlie.

(post #53902, reply #8 of 9)

"Thread width is determined by the architech, or in your case by the amount of space you wish to attribute to each thread. 14 thread at 10" equals for example 11' 9". If you wish to use a 2X12 allow11 1/4" per thread.

Charlie."

Hope you don't take offense at a minor correction. Threads are what we wear or this discussion is a thread. Treads are what we walk on in a set of stairs. There is a difference too in a tread and the layout run of a set of stairs. If I assume a nosing of 1-1/4", then a run of 10" will give me a tread of 11-1/4"

.

.

Excellence is its own reward!

 

 

Oh Well,

We did the best we could...

(post #53902, reply #9 of 9)

Thanks for the correction; I do not know why I misspell that word. As far as the nosing strip it should not calculated into the stringer layout. Also Phil remember to take the thickness of the tread!! from the height of the first riser.


Charlie