# cutting stair stringers



## BigJim (Sep 2, 2008)

You will have 17 risers divided into 129.25" the run will be 10 inches.


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## titanoman (Nov 27, 2011)

F.Y.I code says no one step can vary more than 3/8" from the others. Don't forget to allow the thickness of you tread material on the first tread cut (bottom).


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## paul100 (Aug 29, 2009)

Try this stair calculator 
http://www.blocklayer.com/Stairs/StairsEng.aspx


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## jimmy21 (Jul 2, 2008)

jiju1943 said:


> You will have 17 risers divided into 129.25" the run will be 10 inches.



then my stairs would be in the dirt with the front of the first step touching the concrete.



I got it figured out though. Subtracted 8 1/2 (7 inch step plus 1 1/2 tread) from my original 129 1/4 calculation, to give me 120.75. divide that by 17 and i ended up with roughly 7 3/32. To give me the distance needed to get on to the concrete i went with 11 1/2 runs. This made the back of my stringers clear the concrete by 8 inches or so. Stuck them in place, and they look perfect. Glad it worked out, cuz i was sure pulling my hair out earlier. The real problem i was having was that i kept thinking my 20' 2x12's were too short


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## woodworkbykirk (Sep 25, 2011)

titanoman said:


> F.Y.I code says no one step can vary more than 3/8" from the others. Don't forget to allow the thickness of you tread material on the first tread cut (bottom).



that must some wacky american code, in canada its no more than 1/8 variance between risers.. if you have to make it up you add or subtract 1/16 over 6 rises, cant do it all at once

also with a total rise of 129", you have to have a landing.. code requires a resting point as soon as a flight of stairs has 13 or more risers


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## titanoman (Nov 27, 2011)

Canada must have the wacky codes . Half the houses in America have a 9' basement which is 15 risers with no intermediate landing. Thats just silly.


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## kwikfishron (Mar 11, 2010)

You're only required to have a landing at the 12’ mark of rise here, regardless of the number of steps.


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## titanoman (Nov 27, 2011)

kwikfishron said:


> You're only required to have a landing at the 12’ mark of rise here, regardless of the number of steps.


Now that sounds more like it.ki


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## Keith Mathewson (Sep 1, 2010)

There are a number of problems here-

The pad was poured before the stair was drawn out and so isn't in the right place.

A 20' stringer is too long for a single flight of stair, it will be bouncy and perhaps over stressed.

The sub-tread, roofing and 3 1/2" tread material? What's going on?

There should be a landing on this stair.

That'll do for now, do you have a jack hammer?


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## titanoman (Nov 27, 2011)

Keith Mathewson said:


> There are a number of problems here-
> 
> The pad was poured before the stair was drawn out and so isn't in the right place.
> 
> ...


Well of course you can use a mid-span post if theres no wall to attach to (?).
The mid-span landing? No reason. And then they would really miss the concrete.
And I don't get the plywood or roofing either.


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## jimmy21 (Jul 2, 2008)

I'm not worried about supporting mid span, that's not. Problem. But having a landing required would suck. The concrete is plenty big enough so I have room to extend farther. It just couldn't be too short. The roofing is because this is a combination carport and deck. It has torch down roofing and then I'm putting 2x4 sleeepers down and then screwing the deck to the sleepers, to not puncture the roofing.


The only reason I'm building a deck/stairs is the building inspector said I need permanent stairs up to my storage trusses. He said I have too much headroom up there and it therefore requires permanent stairs. The original pull down stairs don't count.


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## Keith Mathewson (Sep 1, 2010)

Please tell me how a mid span post counteracts lateral forces?
And That's why there are building inspectors


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## titanoman (Nov 27, 2011)

Keith Mathewson said:


> Please tell me how a mid span post counteracts lateral forces


Not a lot if one of the stringers isn't anchored to a wall.
And it's totally legal in california,/everywhere.


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## woodworkbykirk (Sep 25, 2011)

any person walking up or down a flight of stairs will develop a memory in regards to how much to raise their foot to walk up the stair comfortably,, any more than 3/16" becomes very awkward and makes it more likely for the person to trip.. hence our code of max riser variance of 1/8"

what are you framing your stairs with to have more than 13 rises in a straight flight of stairs and not have issues with the stair sagging our bouncing? 2 ply lvl's

we have much stricter codes in a number of areas for different trades


one of the scariest ive heard is regarding your electrical,, cant remember teh exact distance but you can have as many outlets as you can fit within so many feet. here you cant have more that 12 outlets or light boxes per circuit. with out code electrical fires are far less likely to happen as


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## jimmy21 (Jul 2, 2008)

woodworkbykirk said:


> any person walking up or down a flight of stairs will develop a memory in regards to how much to raise their foot to walk up the stair comfortably,, any more than 3/16" becomes very awkward and makes it more likely for the person to trip.. hence our code of max riser variance of 1/8"
> 
> what are you framing your stairs with to have more than 13 rises in a straight flight of stairs and not have issues with the stair sagging our bouncing? 2 ply lvl's
> 
> ...


I think here your allowed 1/4 or more varience. But it doesn't matter, my stairs turned out perfect. Within 1/16. This had 10' of rise because its 8' of headroom, plus a 2x12 plus 18" grade change.

I'll just have to call the ahj tomorrow to find out about a landing. Hopefully it really is 12' rise. Which I'm only at 10'9. Landing would be stupid in this situation. This is just access to storage over my garage. If the stairs have significant bounce I will just put posts under the midpoint. The stringers are 2x12 reinforced with 2x4


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## titanoman (Nov 27, 2011)

Or frame under the stairs and call it storage.


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## BigJim (Sep 2, 2008)

jimmy21 said:


> I think here your allowed 1/4 or more varience. But it doesn't matter, my stairs turned out perfect. Within 1/16. This had 10' of rise because its 8' of headroom, plus a 2x12 plus 18" grade change.
> 
> I'll just have to call the ahj tomorrow to find out about a landing. Hopefully it really is 12' rise. Which I'm only at 10'9. Landing would be stupid in this situation. This is just access to storage over my garage. If the stairs have significant bounce I will just put posts under the midpoint. The stringers are 2x12 reinforced with 2x4


If you cut an 11 + run out of a 2X12, you will for sure have bounce if not dangerous, that is getting a little thin on the back of the rise/run cut.


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## jimmy21 (Jul 2, 2008)

Found my answer on the landing. 12' is correct. So I'm in the clear on that


R311.5.4 Landings for stairways. There shall be a floor or landing at the top and bottom of each stairway. Exception: A floor or landing is not required at the top of an interior flight of stairs, provided a door does not swing over the stairs. A flight of stairs shall not have a vertical rise greater than 12 feet (3658 mm) between floor levels or landings. The width of each landing shall not be less than the stair-way served. Every landing shall have a minimumdimension of 36 inches (914 mm) measured in the direction of travel. 


To take care of bounce, I'm going to reinforce them with 2x6. If it still has bounce, i will put 2 vertical posts with a horizontal at mid point


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## jimmy21 (Jul 2, 2008)

jiju1943 said:


> If you cut an 11 + run out of a 2X12, you will for sure have bounce if not dangerous, that is getting a little thin on the back of the rise/run cut.


I was left with 5.5. Didn't seem any smaller than any other stringer to me. Its perfect for a 2x6 to sister to


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## Willie T (Jan 29, 2009)

Removed by poster.


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## Willie T (Jan 29, 2009)

This one should get you just what you are looking for. And, using 17 treads, it keeps you within code, except for the fact that you can only go 84" on a span with cut stringers like this, not 170+. You'd be within code, I believe, if you used solid stringers.
This drawing assumes 1-1/2" thick treads. And it puts one tread at the top deck height.


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## Willie T (Jan 29, 2009)

While I'm thinking about it...............

Since there always seems to be a lot of concern about not leaving enough "meat" in the stringers after cutting out for the risers and treads..... I do hope everyone knows THIS trick....

All you do is shift your cut layout 1" out into the space alongside the 2x12.

This gives you one more (additional) inch of supporting run in the stringer without sacrificing anything.

It is not necessary, at all, to have those "points" on your stair stringers. In fact I know that some of you who have cut many stringers have knocked off a corner every now and then. What did you do? You probably picked it up and tried to glue or tack it back into place...... Right? Do you honestly think that did a bit of good? C'mon, think about it. The points do nothing. You never even nail out there, and the riser boards support the treads anyway..... NOT that flimsy, fragile point of wood.

This drawing shows stringers made for identical rise and run.... one cut with points (thus leaving you with only 5-1/8") and one with a shifted layout (leaving you with 6-1/8")

You sometimes have to learn to think outside the box. But keep in mind that stringers of this type and length would be illegal on a deck.


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## titanoman (Nov 27, 2011)

Willie T said:


> While I'm thinking about it...............
> 
> Since there always seems to be a lot of concern about not leaving enough "meat" in the stringers after cutting out for the risers and treads..... I do hope everyone knows THIS trick....
> 
> ...


Unless you're not using risers. And, before you have a pattern, you really need a framing square, which will be tricky for the layman (not you or I) to figure w/o that leading point to measure from.


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## Willie T (Jan 29, 2009)

titanoman said:


> Unless you're not using risers.


Then it is still only aesthetics. The support from a tread with no risers comes from the thickness of the tread, not from that little corner that you wouldn't dare tap with a hammer (or nail into).

As you walk up those stairs, you are depending on the quality of the fastening system toward the rear of the treads.

Does it look better with the points still there? Sure. But that is about all they really do.


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## Willie T (Jan 29, 2009)

titanoman said:


> Unless you're not using risers. *And, before you have a pattern, you really need a framing square, which will be tricky for the layman (not you or I) to figure w/o that leading point to measure from*.


True. But, although I just wing it, there is an easy way a novice could handle that challenge.

Rip a 1" piece to lay next to the raw, uncut stringer, and work off that edge.


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## woodworkbykirk (Sep 25, 2011)

referring to how much meat is left in the stringer after the notches are made is called "effective depth",, a 2x10 stringers is the minimum allowed here, it just works out to have 3 -1/2" of depth left in the stock. i use 2x10 for stairs with up to 7 rises, then i either up it to 2x12 or even 11- 1/4 lvl's for long flights of stairs.. you want a stair with nearly no bounce at all use lvl.. heavy as hell though..


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## titanoman (Nov 27, 2011)

woodworkbykirk said:


> referring to how much meat is left in the stringer after the notches are made is called "effective depth",, a 2x10 stringers is the minimum allowed here, it just works out to have 3 -1/2" of depth left in the stock. i use 2x10 for stairs with up to 7 rises, then i either up it to 2x12 or even 11- 1/4 lvl's for long flights of stairs.. you want a stair with nearly no bounce at all use lvl.. heavy as hell though..


I would never go down to 2x10 for any reason. As it is, that leading corner is always ready to break off anyway because of the way the grain runs, but still...


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## jimmy21 (Jul 2, 2008)

The stairs don't seem to have too bad of a bounce. Enough that it would be annoying in a house but mine will rarely be used. Have to actually jump to get movement. The real problem seems to be racking back and forth. Maybe it would go away when the stairs are complete but just with treads on, it moves pretty easy. Im going to sink some 4x4 posts into the ground to double as reinforcment and part of the railing system.


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## titanoman (Nov 27, 2011)

jimmy21 said:


> The stairs don't seem to have too bad of a bounce. Enough that it would be annoying in a house but mine will rarely be used. Have to actually jump to get movement. The real problem seems to be racking back and forth. Maybe it would go away when the stairs are complete but just with treads on, it moves pretty easy. Im going to sink some 4x4 posts into the ground to double as reinforcment and part of the railing system.


Run the posts all the way to the ceiling and it'll take out all the lateral sway.


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## jimmy21 (Jul 2, 2008)

titanoman said:


> Run the posts all the way to the ceiling and it'll take out all the lateral sway.


What ceiling? Oh wait, your thinking cuz I said its up to storage? I have a carport off the side of my garage and these stairs go from the side of the carport into the middle of my yard. I'm talking about concreting posts 30" or so into the ground (like a fence post) and up to railing height for the stairs. Should take out all lateral sway and bounce and make very secure rails


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## titanoman (Nov 27, 2011)

jimmy21 said:


> What ceiling? Oh wait, your thinking cuz I said its up to storage? I have a carport off the side of my garage and these stairs go from the side of the carport into the middle of my yard. I'm talking about concreting posts 30" or so into the ground (like a fence post) and up to railing height for the stairs. Should take out all lateral sway and bounce and make very secure rails


Oh, I gotcha. Yeah, you should be fine the way you're doing it. By the time you have the railing up everything will stiffen up.


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## Willie T (Jan 29, 2009)

If it doesn't, just add an "X" brace to the two 4x4's. (Keep the bottoms of the "X" high enough that you can run a lawnmower past them.)


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## jimmy21 (Jul 2, 2008)

I'm getting some conflicting information, what is the acceptable range for a stairway handrail? One person told me 36-38 and one person told me 38-42. Isn't 38-42 the height of a guard rail up on the deck, not on the stairs?


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## titanoman (Nov 27, 2011)

jimmy21 said:


> I'm getting some conflicting information, what is the acceptable range for a stairway handrail? One person told me 36-38 and one person told me 38-42. Isn't 38-42 the height of a guard rail up on the deck, not on the stairs?


36" measured at the nose of the treads.


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## Gary in WA (Mar 11, 2009)

This should clear things up a little; pp.17-need risers, fig. 27 max. stringer span 7'; 5"min, throat, 16'6" max. closed stringer span; pp.2- table 1; fig.31- top stringer hanger required; fig.34- post footing depth to reduce stringer span; ect. etc.
http://www.awc.org/Publications/DCA/DCA6/DCA6-09.pdf

And, always check locally for amendments to codes.

Gary


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## Willie T (Jan 29, 2009)

GBR in WA said:


> This should clear things up a little; pp.17-need risers, fig. 27 max. stringer span 7'; 5"min, throat, 16'6" max. closed stringer span; pp.2- table 1; fig.31- top stringer hanger required; fig.34- post footing depth to reduce stringer span; ect. etc.
> http://www.awc.org/Publications/DCA/DCA6/DCA6-09.pdf
> 
> And, always check locally for amendments to codes.
> ...


Thanks, Gary. I'm embarrassed to say I missed this. It is, after all, a deck.


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## titanoman (Nov 27, 2011)

Willie T said:


> Thanks, Gary. I'm embarrassed to say I missed this. It is, after all, a deck.


Do I detect any sarcasm there?


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## Willie T (Jan 29, 2009)

titanoman said:


> Do I detect any sarcasm there?


???? Not at all. I am truly embarrassed that I missed something so basic. 28 years as a GC, I should know better.


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## titanoman (Nov 27, 2011)

Willie T said:


> ???? Not at all. I am truly embarrassed that I missed something so basic. 28 years as a GC, I should know better.


Okay. First I thought you were serious, then I thought you were being sarcastic when you said "after all, it is a deck" (not a piano).


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## Willie T (Jan 29, 2009)

titanoman said:


> Okay. First I thought you were serious, then I thought you were being sarcastic when you said "after all, it is a deck" (not a piano).


No, I meant it's a deck, and that I should know full well that decks have their own separate codes, restrictions and requirements.


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## Willie T (Jan 29, 2009)

BTW, Gary is one of only a handful of people I have the utmost respect for. If he says something, you can usually take it to the bank.


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## jimmy21 (Jul 2, 2008)

GBR in WA said:


> This should clear things up a little; pp.17-need risers, fig. 27 max. stringer span 7'; 5"min, throat, 16'6" max. closed stringer span; pp.2- table 1; fig.31- top stringer hanger required; fig.34- post footing depth to reduce stringer span; ect. etc.
> http://www.awc.org/Publications/DCA/DCA6/DCA6-09.pdf
> 
> And, always check locally for amendments to codes.
> ...


Looked that over, looks like I need more posts. I currently have posts centered, which is like 9' in each direction


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## jimmy21 (Jul 2, 2008)

Is 7' span measure level or measured at a diagonal along the stair?


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## Willie T (Jan 29, 2009)

Level

You might have to shift the landing to the next higher step than I've shown, or make the landing longer. Eight treads on the bottom and eight treads on the top would work out just about right. (I was just too lazy to redo this drawing after I saw that I miscounted.)

Don't forget you can make a 90 degree turn in the stairs at the landing to use up less yard space. Or even a 180 degree switch back if you want.


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## jimmy21 (Jul 2, 2008)

Out of pure coincedence my supports are 7' on center. 9' measured diagonally along the stringer but 7' going level. Things are working out. And the stairs stiffened right up with the posts


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## Willie T (Jan 29, 2009)

jimmy21 said:


> Out of pure coincedence my supports are 7' on center. 9' measured diagonally along the stringer but 7' going level. Things are working out. And the stairs stiffened right up with the posts


Check to be sure that's legal without a landing. (If I'm reading you right.)


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## kwikfishron (Mar 11, 2010)

GBR in WA said:


> This should clear things up a little; pp.17-need risers, fig. 27 max. stringer span 7'; 5"min, throat, 16'6" max. closed stringer span; pp.2- table 1; fig.31- top stringer hanger required; fig.34- post footing depth to reduce stringer span; ect. etc.
> http://www.awc.org/Publications/DCA/DCA6/DCA6-09.pdf
> 
> And, always check locally for amendments to codes.
> ...


Good catch Gary…….no southern pine in Oregon so the 13’3” would apply for a free span. A mid span support would negate that though. For a long run like that I will use 3 or 4X PT stock which I know is readily available in Oregon but is a special order pita where I’m living at now.


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## jimmy21 (Jul 2, 2008)

Willie T said:


> Check to be sure that's legal without a landing. (If I'm reading you right.)


Landing isn't needed but I'm going to check with the ahj to go over everything just to make sure of everything


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## Willie T (Jan 29, 2009)

Just in case, here are the other two views.


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## jimmy21 (Jul 2, 2008)

Met with the building inspector, he said 11' on the landing, which I'm not over. He also said my supports are good. So evetything is fine.


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## Willie T (Jan 29, 2009)

Great!


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## jimmy21 (Jul 2, 2008)

Only thing that threw me for a loop was he says I need a grippable habdrail and the 2x4 i will have on top will be too wide. So I'm gonna need to fabricate something to come off my rail


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## Willie T (Jan 29, 2009)

Just install a grippable rail right on top of your 2x4.


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## kwikfishron (Mar 11, 2010)

Willie T said:


> Just install a grippable rail right on top of your 2x4.


That looks retarded in imo Willie.


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## Gary in WA (Mar 11, 2009)

Pages 18, 19---- fig. 32a, 32b, and 33: http://www.awc.org/Publications/DCA/DCA6/DCA6-09.pdf Again......


I'll bet you didn't read it all, Lol.

Gary


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## jimmy21 (Jul 2, 2008)

kwikfishron said:


> That looks retarded in imo Willie.


I thought about doing that just for my inspection and then removing it, but id rather just have something permanent, so its never an issue. My neighbor is in welding school and likes little projects, might just have him weld me some stainless brackets and atatch a 2x2 that's been routered. Neighbor doesn't charge me anything, not even materials


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## kwikfishron (Mar 11, 2010)

I use 2x3 Clear Cedar for exterior grab rails with a ¾” round over on all edges. Mounted with aluminum brackets (I wish I could get them in SS) just like an interior railing.

I’ll actually rip the 2x3 to 2 ¼” wide because I think the 2 ½” wide is just a little much for a grab rail where 2 ¼” feels perfect to me.


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## SteelToes (Oct 5, 2010)

I've seen people using 1-1/2" galvanized pipe here in Chicago.

They use a floor flange and an elbow to start off and a tee for the joints.

Much more durable than 2x2 or 2x3 IMO.


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## jimmy21 (Jul 2, 2008)

If I was going to go the steel route I would just weld the whole thing up, but time and money are both short


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## Gary in WA (Mar 11, 2009)

Whatever you decide to go with, make sure it meets minimum code, just much safer and no liabilities. 

The 2x3 ripped and routered corners does make a nice handrail. Make sure it is 1-1/2" x *1-7/8"* when done to meet the max. perimeter size per Code. 2-1/4" = 6-7/8" 2' = 6-3/8" still larger than max. of 6-1/4". http://www.arcways.com/pdfs/IRC2006.pdf

Gary


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## CVGFir (Jun 1, 2009)

Check out StairBuilderPro for the iPad. Does stair layout in minutes in an easy to use and unique method. You will find it useful.


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