Replies

1. 
   DanH | Aug 12, 2015 02:51pm | #1

   Generally the structure must be designed such that a ball of some diameter (I'm thinking it's currently 4" -- used to be 6") will not fit through anywhere.  Assuming your pickets are vertical, the angle of the stairs has nothing to do with it.

   Eg, if the presumed ball is 4", the pickets are 3/4" thick, and the distance between posts (from left edge of right post to right edge of left post) is 38 1/2", divide 4 3/4" into 39 1/4" and take the next larger integer.  The result of the division is 8.26, so take 9.  That's how many spaces you have between the pickets (you will have 8 pickets).

   The spaces are ((38 1/2) - (3/4)) / 9 or 4.1944" -- about 4 3/16", center-to-center.

2. 
   deadnuts | Aug 12, 2015 06:33pm | #2

   Depends on whether you have an open or boxed staircase. On open stairs your balusters should meet code (4" sphere rule)  with  same layout on each tread. Usually this is 2 balusters per tread, but some designs may require 3. So, in other words, if your design requires 3 balusters for each tread, then all treads will get 3 balusters at corrsponding layout. The balusters for a boxed stair condition should follow code and can be spaced evenly along the boxed stringer, irrespective of tread locations.

3. 
   icerunner | Aug 13, 2015 11:03am | #3

   Thanks! It is 4" here and my

   Thanks! It is 4" here and my pickets are 1.5" square so I'll adjust the calculations.

4. 
   icerunner | Aug 20, 2015 11:50am | #4

   picket spacing

   I still can't get an even spacing, or even close. So with the 31 degree stair angle, do I measure "level" between the outside posts or measure along the board connecting the two post at an angle? I've tried it both ways and sill come up with an 'odd' space at the other end from where I measure.

   So, I tried it on my 'level' railing and still have the same issue. SO, I broke out my Taunton "Building a Deck" by Scott Schuttner and on page 137 one can see that though the author uses a 4" spacing block, the pickets ()balusters) are not 4" at the ends. Maybe I'm just wasting my time and should use a 4" block and not worry about the ends.

1. 
   florida | Sep 03, 2015 09:15pm | #10

   Okay, I'll let you in on the secret of baluster spacing. Use a metric tape.  Since metric is in units of 10 the spacing is easy to calculate. 4" equals 102 mm. If I'm using PT balusters I space them at 3 3/4 to allow for shrinkage.

1. 
   deadnuts | Sep 04, 2015 02:31pm | #11

   I always wondered why there was a big push for the U.S. to adopt the metric system in the 1970's: baluster spacing!

   Oh well, must not have been enough deck builders out there to make this happen. I guess everyone is stuck spacing their balusters at 4". That is, unless, we're using P.T. lumber where we can really mix things up a bit and use the 3-3/4" mark (before converting this to mm, of course) on our tape measures.

   Hey, what about bungee cords and Sharpies? Anyone?

5. 
   deadnuts | Aug 20, 2015 05:50pm | #5

   Go for even dimensions for all spaces

   it's the right way.

   If you're measuring on the angle, then you have to use the pickett dimension width measured when set at an angle (it will be slightly more). Same as measuring the angled leg of a parallelogram.

   Here's how you do it for any unit you want to lay out evenly (columns, picketts, whatever--of any unit width). For stepping out on an angle: Take the total rake angle length and then add one (angled width) pickett unit to that measurement. Divide out by number of picketts. That will give your centers. When you start your layout set that first center dimension from the beginning piont and then step back from that one half of one pickett unit. That is a critical step that most forget. From there simply step off all other centers. Use dividers or a calculator to avoid accumulated error. If you did it right, then  when you scribe out the width of each pickett, you will see that they are all the same dimenson between picketts.

   It always works. If it doesn't, then your math or layout marks were wrong. Double check them.

6. 
   DanH | Aug 20, 2015 09:05pm | #6

   Look at it this way:

   Say you have a 35" space (from the right side of the left newel post to the left side of the right newel post), and you must block a 4" ball.  And say your pickets are 1.5" wide. 

   So the maximum center-to-center distace between pickets is 4" plus 1.5" equals 5.5".  Divide 5.5 into 35 and you get 6.36. 

   Since you can't have 0.36 of a picket, that means you will need 7 SPACES between pickets.  But if the SPACE "belongs" to the picket to the right, the right-most space has no picket but "belongs" to the right newel post, so you only need 6 pickets.

   Now it gets tricky.  There are 6 pickets and 7 SPACES in that width. If we simply divide 35 by 7 we get 5", so it would SEEM that you should put the pickets on 5-inch centers.  But if you do that you're neglecting the fact that we measured the space between newels the way we did.  Instead, consider we have 35 inches minus the width of 6 pickets (9 inches), or 26 inches to divide 7 ways (to get 3.714") -- this is the space BETWEEN pickets.  Add 1.5 inches and we get 5.214", a nice round number.  (Trick:  Set aside the 5 and multiply 0.214 times 32.  You get 6.8.  Round to nearest (7).  So 5.214 inches is approximately 5-7/32".)

   So your center-to-center spacing is 5-7/32".

   (At least that's true if I didn't screw up somewhere.)

7. 
   deadnuts | Aug 20, 2015 09:59pm | #7

   Why make it confusing?

   Dan's math is correct. Total space + one picket divided by 7 is, indeed 5.21". But why make it confusing with your meandering explanation? Your dividing spaces, Dan, not picketts*.

   The number of pickets will always be one less than your spaces. Always. To remember this, just think of a single column situated in a room between 2 walls: If there is only one column, there will always be two spaces. The task at hand is solving so that the space on either side of the column is even. It's easy to lay out for one column, but can get confusing (trust me I've seen many an experienced carpenter in a quandry over this) when you get more than one.  Anyhow, you'll never solve for this in our example of one column by simply measuring the lenght of the room and dividing it by 2. You have to add in the width of the column. Likewise, you will always get the exact center point of that column (and numerous others as the case may be) by:

   1.taking the room (or whatever run you have) width

   2. adding the column (material unit) width

   3. dividing that number (derived by step 2) by the number of spaces which equals your center-to-center distance.

   4. measuring your center-to-center dimension (derived in step 3) from one wall and then stepping back half the column (unit) width.

   5. Lay out all subsequent center-to-center points from this starting point if you have more than one unit.

   So, the critical stept is knowing where to start your center-to-center layout so that all your spaces are equal or even. That was adressed in my earlier response. That's the way to look at it. End of story.

   *Dan, certainly you can have .36 of a pickett. You do that by ripping it on a table saw. However, that doesn't help explain solving the task at hand.

1. 
   mark122 | Aug 21, 2015 10:15pm | #8

   and Dan is the one meandering?

   would love to see one of your railings with a ripped baluster...maybe you should quandry like experienced carpenters before you go slapping ripped balusters on and calling it a day.

   one method as good as the other, unless yours leaves one ripping balusters!

8. 
   icerunner | Sep 01, 2015 03:26pm | #9

   Thank you! I've got the levels; now on to the angled! Whew,  "(trust me I've seen many an experienced carpenter in a quandry over this)" - and I'm just a blockhead working on my deck so it WAY more trouble.