[jon123]

I want to layout a new set of stringers to replace an old existing one, I want this stringer 7.5 instead of 8" on the rise if possible and..definitely want a 11.5 tread as opposed to the 9.5" tread width existing on this old 16 step staircase. Was hoping someone could start me with how to layout for the top and bottom cuts.. I have slightly off pitch cement walkway below so I must scribe the one stringer to level my stringers. Ty jon

[hkstroud]

Not sure what your question is. To cut off the bottom you extend the cut line for the last step to completely cut off the excess material. At the top, you either extend the line for the riser or extend the line for the step, depending on how you plan to attach the stringers to the deck. See dotted lines on drawings. Lay out stringers for longest one and then trim bottom riser of one to compensate for the unlevel surface.

How you attach the stringers depends on several things like, is your band board inside the deck post or outside. How do you plan to do the hand rail, are pickets attach to side of band board or does the deck boards extend over the band board with pickets attached to deck, my personal preference.

However if you question is "How do I lay out my steps?". Post back.

[ballengerb1]

Several approaches to sertting up stringers, my usual approach is to go to Menards and buy a pre-cut set. How to cut stringers.

[hkstroud]

PM from John

Harold, I have existing cut stringers I want to replace but not duplicate.. existing staircase is (16 step rise with the top rise to deck making it 17 risers) the existing stringer cut at an 8 rise but they used a 9.5 in. (2x10) with no bullnose or 1" overhang on the treads. I wish to increase the tread width to 11.5 (2x12) with a 1" overhang for treads and hoping less than a 8" rise.. preferably, a 7.5 rise.. I'm hoping you could walk me through step by step as how to replace to old ones.. thanks ahead, john

John,

We like to keep things on the form so every one can see.
(It's really so Bob can point out my mistakes.)


Once you know the correct rise and run you are about 80% done. Laying out the cut is fairly simple. You lay a framing square on the stringer aligning the rise on one leg and the width of the step or run on the other leg. Mark it and move you square down the stringer and repeat for the next step.

Frequently Made Errors (FME) (I just made that acronym up)

Forgetting which side of the square you are using. You can use either the inside markings or the outside markings, just be consistent.

When cutting out the notches, pay attention to which side of the line you are cutting. I believe in always "leaving the line", not cutting down the center of the line. When cutting the riser cut, the cut line will be on the right side of the blade. When cutting the step cut, the cut line will be on the left of the blade.




As previously stated, cutting off the bottom is straight forward, you simply extend the step line completely across the stringer. If you are going to make the top step level with the deck, you cut the top like the last drawing in the previous post and nail through the band board. If you want to make the top step one step down from the deck, you put an additional piece of band board below your deck band board and attach the stringers to that.

If you want to attach the stringers to the side of the deck post, you cut the top like the other pattern with the pointy top end and nail or bolt to the side of the post. The former is preferred, not that much material left to nail to the post.

Stop by Home Depot or Lowe's tool department and purchase a set of little clamps which you attach to your framing square to so you don't have to align the square with the edge of the stringer each time. These are just little stops which you clamp on your farming square at the desired rise and run and butt them up against the stringer edge so you don't misread your measurements. Cost about $5.

[hkstroud]

John

Rereading you post, you stated what rise and run you would like to have. Have you measured and know that that is the correct rise and run? Or is it just what you think you want? With 16 steps a small change in the rise of each step can make a big difference.

See this post.

[creahands]

To determine size of tread and riser u will need 2 measurements.

Drop a plumb line from deck. Measure from line to concrete pad. Allow for seat cut to sit on pad.

Get a level line from deck to extend over pad. Measure down from level line to pad. This will give u total rise.

Divide the rise by number of steps u want including deck as last step. This will give u the rise per step.

When u have the rise u want, divide the run by same number and see if u fall on pad where u want. If not u will have to adjust the rise until it works.

Also when using the square clamps it may be easier to use outside numbers. That way u will be able to see the end of your previous mark.

Good luck

Chuck

[jon123]

You guys are GREAT! I haven't started this project yet but see exactly what is needed to do this a lot easier and with more confidence. The original question was basically correcting the existing layout to build cut the run and rise from an existing slab to an existing deck.. I plan on doing this project soon and will certainly keep touch as to how it goes.. getting those clamps for my rafter sq. and will scribe the one base of the stringer to level the rise. Wherever the stringer flys off the top rise is okay so long as my rise and run are true to layout. Thank you for sharing, john

[jon123]

ohh!. few more staircase planning questions.. I want to use pressure treated 2x12x16s or 18s whichever the mill carries.. as for the treads.. I was wondering if 2x12s is preferred for sturdier step as opposed to side by side 2x6s which would likely need a 1x4 cleat underneath for brace support on a 36" step. I think I'm going with 2x12 crown up and just block plain a bullnose. My railings will be 3.5" off the tread (easier to broom snow off sides) and I will certainly have my 4x4 supports three on each stringer with 36" to step 2x4 railings

[hkstroud]

It's your project but if it were me I would use 3 stringers and deck boards for treads. While the 1 1/2" thick 2x material will span 36" but you are likely to have some bowing as the material dries and as it gets wet and dries out over time. You can use the 2x6 or the 2x12 but it will look a bit heavy for my preference. If you use 2x12 you may have some cupping. You are more likely to have water and ice accumulation with the 2x12. The 2x6 or deck boards (which are 1' thick) will provide better water run off. The deck boards or treated 2x6 will shrink as they dry out. Butted up against one another, not tightly but butted against one another, will prove adequate drainage and the best appearance.

Not sure what the maximum span for supports are for a 2x12 stringers are but 3 post seems a bit much. Not sure what you total run is but it must be approximately 12". One intermediate post giving you a 6' span may be adequate. Two post giving you a 3" span would certainly do.

[creahands]

I agree with Harold.

If u are using deck boards on deck, would use same on stairs with 3 stringers.

If using 2 by for decking, then I would use 2x6 for treads for stairs.

Chuck

[manhattan42]

Below is a link to the Visual Interpretation of the 2006 IRC Code for building stairs.

http://www.stairways.org/pdf/2006%20...C%20SCREEN.pdf

You will likely find it helpful in determining maximum riser heights, minimum tread depths, minimum stair widths, minimum guard rail heights, how to construct graspable handrails, the maximum opening dimensions for guardrails and risers and a host of other things.

[jon123]

Yes, this is why I wanted an opinion for the treads, I know how to crown my hand picked lumber. I agree 1x6 decking is better in appearance. I will consider harolds option using a third stringer. Ty all, john

[jon123]

okay, I'm starting this staircase project soon.. got the sq.clamps and know my rise is 129" top of deck to slab which is level out to where the bottom step land. Including the top deck I have 17 steps total.. I used a calculator..divided 17 into 129" =7.588.. round off should give me 7.5 rise with two 2x6s for the tread ( I can always screw 1x4 underneath center if I feel the need on doubled 2x6 treads. I'm keeping the ballists off steps about 3" for brooming snow... my rails will be basic 2x4 ..with bolted 4x4 posts 36" off first step to top deck rail.. midway I'm using 10ft 4x4 between total span on staircase. Ballists spaced min.requirement think is around 3.5 " ty you all again, john

[hkstroud]

17x7.5=127.5

You are 1.5" short.

Eighteen steps would be better.
18 x 7 3/16 = 129.37

To come any closer you would have to measure and cut to the 32nd (7 7/32).


Stringers should come up to top of band board. That is, the underside of the deck boards, if you are using 2x deck boards. Remember you are going to be putting a tread on the top step.

After cutting stringers, cut 1 1/4" off bottom end. That will lower top of the tread of the bottom step to 7 3/8. Otherwise the bottom step with tread would be 8 5/8 (approx).

[manhattan42]

Don't forget that in New Jersey you will also need:

A graspable handrail that terminates into newel posts, returns into the wall, or is part of the guardrail.

(A 2x4 or 2x6 on edge that is part of a guardrail is not considered 'graspable' and will not meet code.)

You also will need solid risers or openings in the risers less than 4inches.

2x6 treads are also a code violation because there is no 'radius of curvature' of maximum 9/16ths on the tread nosing. You may be required to use 5/4" decking for the treads if your inspector won't make allowance for 2x6 tread material. Many won't. Find out from your inspection office before you plan further. You'll need to know before you go in for your permits anyhow.

[jon123]

graspable handrail I can see as code.. but mandated risers I will have to check on that.. I could argue that risers would make it difficult for brooming off winter snow. Although risers as you say worse case should I need too put 1x4 on the higher portion of the rise.. and the choice of wood for treads be it 2x6 cleated or a solid 2x12 if not code I will either router my own radius or check other options available. It is starting to look like I may opt for a middle stringer and go 5/4x6 decking for tread. Ty for sharing,john

[hkstroud]

Manhatten

What is the interpretation in NJ of this restriction

R311.5.3.3 Profile.
The radius of curvature at the leading edge of the
Tread shall be no greater than 9/16 inch (14.3 mm).

Just from reading, the restriction does not appear to require any radius. In other words, a square edge does not exceed the 9/16 restriction. If a radius is applied, the restriction would seem to be for the purpose of preventing a sharp edge from resulting. That is to say that a 2" radius is applied to both sides of a 1" tread the result would be a very sharp edge to the tread. This interpretation would seem to be consistent with limit of 1/2" depth of a bevel edge.

What does NJ do about masonry or brick steps?

[manhattan42]

One needs to read the entire code section... not just portions of it... to get the full intent.

R311.5.3.3 (2006 IRC) says that the curvature of radius for the leading edge of a tread cannot exceed 9/16". The Code also says leading edges of treads can beveled a maximum of 1/2"...

A nosing that projects not less than 3/4" and not more than 1 1/4" shall be provided on all stairways with solid risers.

Nosings are not required if the tread depth is greater than 11" on stairs with solid risers. (Exception 1 to R311.5.3.3)

Since a 9/16ths inch curvature of radius results in a diameter of 18/16ths or 1 1/8th inches...many inspectors consider this to mean that the maximum tread thickness can be a nominal 5/4" (18/16ths inch) and why I mentioned the 'issue' in the thread.

In other words you cannot put a 9/16" radius on the full nose of 2" nominal treads.
------------


The answer then, depends upon how Jon123 ultimately constructs his stairs and what his inspector requires.

IF he uses solid risers...
And IF his treads are less than 11" in depth...
THEN he will need to have a nosing on the treads that projects beyond the risers between 3/4" and 1 1/4" AND IF he uses a rounded nosing, the curvature of radius can be no greater than 9/16ths of an inch.

IF he keeps open risers with openings less than 4"...

... he is required to have no nosings at all.

Same requirements apply to brick or masonry stairs that are part of the primary means of egress from the structure. It doesn't apply to landscaping stairways.

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Jon123 does need to be aware of the design limitations above, and consult his code inspector now before he starts in order to avoid problems after it is inspected.

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Personally, as an inspector, I have no problem allowing 2x treads for deck stair construction, but some inspectors do have a problem with it.

As a builder, I have had some inspectors fail my deck stairs because I have used 2x stock for treads. (shrugs)

So it is better to find out BEFORE one starts to construct the stairs what the inspector is looking for, and it may be necessary to describe in detail how one plans to construct the stairs in order to get permits anyhow.

[hkstroud]

AND IF he uses a rounded nosing, the curvature of radius can be no greater than 9/16ths of an inch.

I guess that's my point or question, the IF part.

Doesn't seem to prohibit a square nosing.

[jon123]

I am deciding with 2 5/4 x6 decking and three 2x12 stringers with a 1 in. overhang. The treads will be 36 wide with the stringers set in one inch on both sides.. should be solid enough with about 16 oc for the deck treads. Would you say I use #8 galv ring shanks full round heads in my portacable framing gun or go with pre drilling and deck screws?