Code here is >4". They have a ball that they use.

 

I think there is also a 6"(?) ball for stairs between the bottom rail and the tread/riser.

Despite the formulas and methods, the thing that will catch you is the real world when the inspector's ball slides through.

 

What teetor said. 4" sphere cannot fit between spindles.

 

see if this works

span = 36'
spindles = 1 1/2"

4" min code plus 1 1/2" = 5 1/2"

36 / 5.5 = 6.545454 (7 sets that's 6 spindles and 7 spaces)

Take 36 - (6 x 1 1/2") then divide by 7

each space is 3 7/8"

zzzzzzzzzz monster :sleep1:is nearby so use this info at your own risk

 

I think I understand what you are asking. It's not the code but a formula to figure out equal spaces, right?

Here's my attempt. Take the total distance between newel posts...say for instance it's 10'...or 120".

Then measure the thickness of each spindle at their base...say it's an inch and a half. Multiply that measurement by the total number of spindles...say there are 30 spindles.....so 30 times 1.5" is 45". Subtract 45" from the total span which was 120"...so you have 75". Now you divide that number by the number of SPACES you will have between spindles....that will be 31 (always one number higher than the number of spindles). In this hypethetical example (I pulled numbers out of my a**) the correct spacing would be 2.42" or about
2-3/8"+.
Hope this helped...it's harder to explain than to do. If you don't get this, come back and give me the numbers and I'll figure it out.

 

Damn you wallmaxx and your fast typing.

 

Hey, I haven't done railings in a while, but just to clarify for future reference, the 4" rule applies to the narrowest part of the spindle, correct?

 

It applies "center" to "center": "Center" of the spindle/balluster - to the "Center" of the next spindle/balluster.

 

Atlantic; yes centerline, therefore using 1.5" spindles the MAX center to center distance will be 5.5". For real comfort I use 5 1/4 MAX, since the real test is that " a 4" diam ball cannot pass thru the space between the spindles"
The real "gotcha" is to make very very sure you have LESS than 4" bwtween them at their SMALLEST dia!!!!!! IE tho the bottom of the spindles may be fine CHECK AT THE TOP WHERE THE SMALLEST PART OF THE TAPER IS If the ball passes thru there no matter that it doesnt at the bottom you fail. You may find that you have to go down to maybe 3 1/2 or 4 on center at the base to comply

 

3.5

 

Around here according to code we are allowed a 4" space between each spindel (ballast) edge to edge. I always make sure that I place my ballasts 4" O.C. that way they is no way I will get a code violation. I might have to use a few extra ballasts but it makes a stronger railing and allows me some extra room to make my railings look evenly spaced.

 

Is that 4 on the slope or horizontal?

 

I know that the baluster spacing is 4" on a landing and 4 1/4" up the stair. That is the UBC code. I just had to look it up for a job I'm going to do. I found the best way to space balusters is using their centers not the sides, that way I can use a compass. I bought a cheap one at the hardware store. I set it to 4" plus the thickness of the thinest part of one spindle. I then walk it along the path of the rail. I can use this system on curved stuff and straight. You have to make allowances for either end, ei. the start and end points. It seems kind of confusing but man it works great. I don't do well with making computations and they never really work out that well for me. I'm better at laying it out on the work and messing with it from there. I was shown this technique a year or so ago by a guy that was doing a work shop for a local lumber yard. What a character. He called him self the Stairguy and wow did he build some incredible stairs. Most of the stuff he was teaching was real primer print for him but a God send for us. I should try to find out if he has a website. He said he was working on a stair build video. I wonder if he ever got it done? Any body got ideas on good newel post fastening hardware? I could use some.:notworthy

 

I know that the baluster spacing is 4" on a landing and 4 1/4" up the stair. That is the UBC code. I just had to look it up for a job I'm going to do. I found the best way to space balusters is using their centers not the sides, that way I can use a compass.

Woodtick,
Near as I can tell, that 4 3/8" UBC code space is for open treads only. In their code book figure r312.2 reads:

"Sphere 4 inch cannot pass through (Sphere 4 3/8 permitted on open side of stair treads only)

One local company lobbied hard for the change due to 1/2" iron bals being such a pain on treads in the low 9" range. In that tread range at 4", it required 3 bals per tread, resulting in 3" OC's.... only 2 1/2" between!
Joe

 

It's SIMPLE!
All codes that refer to 4" max spherical spacing are referring to the largest space between components. On turned balusters (spindles) that point would be at the smallest spindle diameter. It's common for a baluster to have a 1 3/4" block at each end, & a 7/8" minimum turning diameter. In such a case, you may as well have a 7/8" dowel rod as far as bals spacing is concerned. The same applies to the newel post also.

It's kinda interesting that LJ Smith still gives faulty formulas in their installation literature. This is because it's still based on old code, on center methodology. It don't work for spherical spacing, because it doesn't take into account the turning diameters.

I prefer to keep the layout simple, & use a the SAME BURY values whether dealing with a turned newel, or dieing into a wall.

Example:
5015 taper (3/4" pin top bals)
4040 nl = 3/4" deep center cut (3" block, 1 1/2" dia center)
code = 4" spherical
On center = 4 + 3/4 = 4.75 oc (max value, use less for error margin)
safe bury value = 1/2 bals min + newel cut depth
(1/2 x 3/4) + 3/4 = 1 1/8" BURY ( @ each end of run)

Spaces = overall run / OC
If wall to nl block = 100" , then oa run = 100 + (2 x 1 1/8) = 102 1/4
102.25 / 4.75 = 21.53 (round up to whole number) = 22 spaces
102.25 / 22 = 4.64 OC ( apx 1/8" less than max code )

First center will start buried in wall or newel 1.125, & then 4.64 OC from there. So 1st center would be 4.64 - 1.125 = 3.52 from wall or nl block face.
Balance of layout is 4.64 OC.

For slope runs, I do the same thing with a converted OC value.
I use a slope conversion factor = to the hypotenuse/base of stair section, or the hypotenuse of the tread rise to run triangle, div by the tread run.
Example:
8 rise , 9 run: sq rt of (64 + 81) = 12.04
12.04 / 9 = 1.34
slope conv fact = 1.34
So, take 1.34 x 4.75 oc = 6.37 OC max on slope run.
You also need to convert the bury value using the same conversion factor.
1.125" x 1.34 = 1.50 slope bury

Note: This conversion factor is actually a secant value of the stair slope angle.
Secant t = hypotenuse/adjacent, where t = the measured slope degrees of the stair.
Tread rise run values are plenty accurate for this conversion factor, but I use the measured slope degrees in my job spreadsheets, since I need the measured degrees for rail assemblies anyhow.
On site, the basic triangle math is simpler using the rise run of a stair tread.

Slope stair layout example, using same 100" between newel blocks, on same 8 rise x 9 run stair :
slope bury = level bury x slope conv fact = 1.125 x 1.34 = 1.50
100 run + 1.5+1.5 = 103" total run.
max slope oc = level oc x slope conv fact = 4.75 x 1.34 = 6.37 oc max
103 / 6.37 = 16.17 , round up to whole number of 17 spaces.
103 / 17 = 6.06 oc ( well below max oc )
1st center buries 1.5" into newel, so from nl face,
so 1st center is 6.06 - 1.5 = 4.55
Balance is 6.06 OC.

The slope conversion factor may seem confusing at first, but is very easy & accurate once you do it a few times.
It's also easy to generate a degree chart on a spreadsheet.
As starting point for stair slope deg and slope conv fact:
42 = 1.34 slope factor
41 = 1.33
40 = 1.31
39 = 1.29
38 = 1.27
37 = 1.25
36 = 1.24

Piece of cake!
Joe

 

Okay then. I think that about covers it. :notworthy

We can put this one to bed:thumbup:

 

if you put the square bottom part of your balluster lined up with your riser,below your tread then space the next one on the tread so that it meets code, the spacing should be the same on all of your treads. given your treads are all the same size. some railings may even need 3 ballusters (spindles), to meet code. then lay your railing on the treads and you can mark your railing and get the angle to drill all at the same time, if your newel post is plum it will even let you mark your length and the angle of cut.i know i don't always explain myself clearly, but this system works out for me, and i don't have to do halucinagenics to figure out some formulas like were given earlier. no offense. if you look at a well built stairway, the ballusters all land on the same spot on the tread. thanks for letting me ramble wink

 

Wink,
Your right about open tread stairs. For them, std layout is 1st bals block face lined up with the lower riser, & then divy up tread run dimension for the tread O.C, while still meeting 4" spherical code. For the rail OC layout, try marking the top, & bottom baluster onto the rail, & then dividing up the overall by the space count. It's easier than trying to transfer every bals center to the rail, & is less likely to have big space errors.

My "hallucinagenic" post referred to cap wall stair rails, which are probably more common today than open tread. Open tread stairs cost more, & hence are used less on most high volume builder homes. If I had gotten into open tread stairs at the same time, it would have just made it more complicated. I doubt anyone would have even read the whole thing!:no:


If anyone has any questions about my posts, please ask away.
Joe

 

Joe, I mean you no offense, but i can put the rail up before i figure out wtf you said.:blink:

 

Wink,
If you draw a rise/run right triangle, & measure the long side, you can find the slope conversion the same way. Just divide the longest side (hyp), by the base (run). That'll give a multiplier to change level on centers 's to pitch on centers. It's just a simple ratio. It's not that hard!

I've seen similar techniques with Norm Abrams, drawing full scale rail layouts on sheets of plywood. This method is light years easier than that.

If all you do is open tread stairs, then it probably won't do anything for you.
Joe

 

Mike,

Ok, maybe I over explain at times. I just that I like to explain the "why" of things, otherwise a post has no reason, or value to it.

I'm not sure which part is confusing, but I'll guess that it's the level to pitch conversion that's confusing. There is no one step process for doing stair layout work. You have to define it, then go through the steps to find the spacing.

example for a level rail section, consisting of:

3/4" pin top bals
newel with a 1 1/2" diameter center
code = 4" spherical
On center max = 4 + 3/4 = 4.75 oc
bury value = 1/2 of bals @ minimum thickness point, + 3/4" newel cut depth (lay straight edge across blocks & meas cut depth)
(1/2 x 3/4) + 3/4 = 1 1/8" BURY ( add to each end of run for over all run)

Spaces = overall run / OC
If wall to nl block = 100" , then oa run = 100 + (2 x 1 1/8) = 102 1/4
102.25 / 4.75 = 21.53 (round up to whole number) = 22 spaces
So now we know how many spaces. Spacing = overall divided by spaces.
So:
102.25 / 22 = 4.64 OC

Does this much make sense?
Joe

 

Hey rail man. When was the last time you installed the serious staircase? All those numbers are enough to make your head ache and your ears bleed. I don't know what you're talking about but it's always the easiest to mark everything off of the center. It is a great methodology in a very practical way. I have to agree with you that a lot of the stuff in the L.J. Smith manual is archaic, but some of it is still very relevant. You are correct to assume that you must take into account the thinnest part of your baluster and of your newel post before you make a decision about your maximum spacing. It also depends on what kind of baluster you using or newel post style. For instance, is it extremely fancy or is it extremely plain? This would have a major impact on what your maximum spacing should be. By the way the pin on a 5015 baluster is usually between 5/8" and 11/16" - 6 inches down from the top. I don't know where you're located, if it's on the East Coast you may be subject to the BOCA code, however in the Midwest and on the West Coast we have to follow something called a Universal Building Code (UBC). They just made some major changes to that code. You now need to have a minimum 10 inch run for your stair treads and a maximum 7 3/4" rise. So that means the old 4 inch spacing is right out the door. What code says now is that you can't pass a 4 1/4 inch sphere through the balusters on the staircase but on the landings you still must maintain the 4 inch rule. You've got to brush up on this stuff man. I have been doing high-end curved staircases in multi million dollar homes for over 25 years. When it comes to the staircases in these big bruisers the inspectors really take you to task because they will not mess with the building code. Not when you have this kind of investment on the line. I obviously need to use a lot a math in my staircases however when it comes to spacing balusters, especially when I'm doing them on a curve, I use a compass. Working everything off of the center of the baluster is a phenomenally easy, quick and accurate way to figure out your spacings. You can also check your work and make adjustments periodically over the course of your span so will you only mess with it once to get it right. That saves time which translates into money. I don't know about you, but I don't like to do things over and over again to get the right spacings. I would like to show it to you sometime, but I think you are probably pretty stuck in your ways. Simplicity is always the best and when I see all these convoluted calculations, to me, it just seems like someone is trying to impress more than educate.

 

Stairguy,
We do about 2,500 preassembled, prefinished sections a year, in about 10 different styles, a dozen std stains, including iron bals. It takes about ten minutes to measure a 40' home, & usually 10 minutes total on the computer to do all the layout, cut list, packing list, & total pricing. We average about 1 bad section every 500 , & in 16 years, I've only had two jobs questioned by a building inspector. I know how to do what we do.

We do a few pre-assembled curve work, but only a dozen or so jobs. We've also done a few curved open tread jobs, with the volute finished, & all holes bored.

I have no doubt you do nice work, & you know what your doing, but so do I.

I do my own lathe work, including part design, pattern templates & cutterhead tooling (Mattison). Not that it matters, but my 5015's are 3/4". I never cared for the 5/8 pin tops, & besides, 3/4" is stronger, faster to cut, makes less shavings in the hopper, & personally, I like a little more bulk.

It seems odd that , I'm the only one that gave a full description of how to do a layout, complete with logic, & examples. I am the only one to catch flack. I'd love to hear anyone explain how to do it in an accurate legal fashion.
The truth is, it's not a simple procedure. So how do you propose to explain it simply?

I'd love to hear how you do yours, & hope to have open conversations in the future.
Joe

 

Stairguy,
When I was referring to the LJS on center thing, I wasn't referring to laying out on center, I was referring to what the old codes were...they were ON CENTER CODES!

LJS doesn't take into account turning diameters because they never changed their formulas to reflect the new spherical codes. Of course all layout work is done on centers, especially when your drilling holes.
Joe

 

One simple way to find the spacing on the slope is to make a rake block (pic1), mark the spacing you want to achieve along the run side of the block. Pulling from the 90 degree corner, mark the spacing you are looking for. In this case, 4" OC (pic 2) then using a speed square (or whatever square you prefer), square down from that mark and put another mark where it intersects with the hypotenuse side (pic 3)....... then measure up from the tip of the rake block as shown, and that's your run measurement (pic 4). In this case, it's 5"... So if you lay out your rake spindles on 5" centers on this particular staircase, you will end up with 4" centers when you measure them horizontally...... which is what matters.

This has nothing to do with the original question I realize but it shows a simple way to get your rake measurement. Rake blocks are a simple, invaluable tool. They can help you figure out all sorts of things.

That being said, I actually think Joe's math method is great, and the more you know and understand math concepts, the better off you are going to be building stairs. I don't understand flaming him. His formula is solid, and will work with any staircase.

 

What a great post. In all my years of making pitch blocks (for fitting cuttings etc) I never thought of using it for rake layout, Thank You.

This (IMO) will work great for kneewall (cap) situations as well.

 

Trimcat,
Great post!
That's what I'm talkin about! You thoughtfully spelled out exactly how you do it, & makes perfect sense.:thumbup:

Using a pitch block easily reveals a maximum rake value, so you can then do the division to get the space count. Then you do the overall divided by space count for the actual spacing. Again, on open treads, you don't need the math because you're only going to do a tread at a time anyway. If it's on a rake cap wall (like over a 2x4 slope wall), you do need to do the math.

If you divide Trimcats pitch block rake length by the run you get the same slope conversion value that I described in my first post. I actually used to use a constant for this value, for many years, because all the stairs I worked with were close to the same slope. Since stairs vary greatly these days, things got more complicated, & hence more math.

The funny thing is, I used to use pitch block when I specialized in interior trim. When I converted to a rail shop, I had to be able to accomplish the same thing on a spreadsheet....so more math!

BTW, my high school trig sucked!
Joe

 

You are right Railman. Instead of pissing down your back I should show you my technique. I have a very intense next couple of days ahead of me however after that I'll take some shots of my process and post it. For now knock it off with all those calculations man. It gives me a headache and I get confuse-ed real easy like, thestairguy.com.:laughing:

 

There are other things it's useful for too. For example, it'll give you the exact angle of your plumb cut on your railing... or anything else you need to cut plumb on the staircase for that matter. Just make a perfect pitch block and the angle that is formed from the rise and the rake sides is the exact angle you'll set your saw on for plumb cuts.

 

It'll also show you how much to add to the length of your starting newel if you notch it into your bottom tread...... I'll have to do another picture series for that one though. Otherwise it'll just be a bunch of words that won't make much sense... Maybe tomorrow