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Somewhere I saw an article or letter-to-the-editor or on-line discussion about how to calculate spacing for deck handrail balusters. I searched the magazine index at FHB main site, but didn’t find anything. Anybody remember the source?
Here’s what we’re going to do: There will be 4×4 posts about 6 ft apart, with 2×2 balusters between them with about 4″ gap. I need to know how to calculate the actual spacing.
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Replies
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Ed:
Measure exactly your face to face distance between your posts. Add to this one baluster thickness, or in your case 1.5 inches. So lets say your posts measure 71 inches apart. Add 1.5 inches and this gives you 72.5 inches.
You want around 4 inch gaps between your balusters. This means that youe center to center should be 5.5 inches. When we added 1.5 inches to the newel spacing, what we are doing is pretending that they are just another baluster. The center of these balusters are then .75 inches in from the edge of the newels.
So all we have to do is divide the 72.5 inches by 5.5 to see how many center to center spacings there are. This figures to 13.18, which when rounded off to 13 gives a center to center spacing of 5.576 inches. Subtract 1.5 inches and you get 4.076 inches between the balusters. If you decide to tighten them up with one more spacing, then you end up with 5.178 inches center to center, with 3.67 inches between them.
So just plug in your actual numbers between the newels, add one baluster width, divide this up to find your desired center to center spacing, and lay it out. Hope this helps. :)
*At the expense of getting nuked for the "easy way out". Center your first picket and install. Use a 4" scrap to get your 4" spacing from there on the ensuing pickets.Be careful with your level and it will look fine. The space between the picket and the support post will show the differences in width but it is not easily picked up by the eyes.Have done it the way Stan suggested and it is a good way but it takes fornever. Have done it the above way and have never had any homeowner or anyone else fuss about the spacing.
*EdAnother way:Lay your tape measure down with the end at the first newel and measure over to the next newl (71" as in Stan's example). Now add the 1-1/2" as Stan suggested (72-1/2") (point b). Dividing this by 5-1/2" does indeed = 13.18. Here's the new part instead of laying it out as Stan suggests, make it 14 spaces. 14 x 5-1/2" = 77". Lay your tape measure down with the end at the first newel again. Pull it over to point b. Draw a line from point b perpendicular to the newels. Move the 77" measure on your tape away from point b along this perp. line until 77" intersects the line. Mark 5-1/2 inch increments with the tape in this position and draw a line perpendicular to your newels at each 5-1/2" mark. I hope this is not to confusing. It saves doing the math for each post space.Good luckTerry
*I was showing the quickest way I know in keeping the spacings all exact.
*Pete if you use Stans method all the spaces are the same, a nice balance look. Your method will yield a mystery space next to the newel which could be 2 inches or 1/2 inch. As for faster, what could be faster than 1 minute with the calculator and you can forget about fooling with the level. But then do what you are comfortable with.
*Terry: I like your method. I see where you are coming from on that.
*Armin: Since you are nearby, if this were a handrail in a house with turned newels, do you treat the newel as if it were just another baluster like I do? In other words, the centerline of each baluster is also the centerline of the newel to the first baluster centerline. I prefer this method as it eliminates the wide gap problem near the top of the newel where the turning is much smaller. This is for newels up to 3.5 inch. Any bigger, then I adjust it a little wider.
*1. Take your face to face measurement and take a guess at how many ballusters there will be. 2. Multiply number of ballasters by their thickness.3. Subtract the answer to step 2 from face to face measurement.4. There will be one more space than balluster, so if you thought there would be 20 ballusters, divide 21 into the answer to step 4 (which is total space).5. Adjust estimated number of ballusters and repeat steps 1-4 untill your answer to step 4 is less than 4" (widest balluster spacing aloowed by code).6. When you think you have the correct spacing make a story stick and test it out, nothing worse than jumping right in and finding out you have a short space at one end. Same principal works for dividing any space equally, just subtract total solids from total length and divide by number of spaces.
*StanI've always done it the way you described. I'm a freak about math. I just suggested the other way as an alternative I've seen. I'm surprised anyone could understand my explanation. I might have guessed you could. I have used this technique to lay out shingle and siding spacing though, it's very fast for this. Terry
*Terry: The way I described is quick for me, and I can see your way. Its interesting to see how everyone does it different. However, if I want the same spacings, I feel it should be planned out, then layed out. Your way, my way, Jims way all come out accurate. We each just have our preferred way to end up the same.
*StanI have wrestled with the baluster / newel spacing and I think your idea of counting it as a baluster is a good one.
*Thanks for all the advice. Not to take sides, but I like Stan's way, with Jim's suggesstion to mark a story pole before starting. I have one of those fractional calculators, so the math won't be a problem. I knew from drafting class many years ago how to divide a line into equal parts, but I can't make marks on the floor, and I don't think I have a large enough square to transfer the marks.
*... Just keep in mind that 4.076 inch clear between balusters doesn't meet code ... as Jim points out.
*Jeff Clarke,"PICKY PICKY!"1/16th difference. C'mon now!Davo
*Lets see...how they say?"If its an 1/8th or less, then don't mess. If it's over a 1/4, better make it shorter!Davo.
*The ultimate, quick and easiest way for a general contractor to handle the installation of the balusters? Let the Sub handle it. heh! heh!Davo.Ahhh, it's past my bedtime. Have a good night y'all!
*Davo - YOU obviously haven't been the victim of the overzealous 'mad dog' building inspector!Remember, some of those requirements used to be written in a performance context, ie, 'cannot pass a sphere of 4" diameter' etc. - when the ball (representing the head of an infant) drops, you lose.PS - It's i morethan 1/16" Jeff
*Thats why I threw in the figures for one more baluster, so that it would be less than 4 inches. These measurements are hypotheticals anyway, but if those figures I was playing with were the actual ones, and the balusters were 1.5 inches wide, then by all means I would make sure I did not exceed the 4.0000 inch figure by even a .001 of an inch. Some of these inspectors can get really anal about measurements. Always better error on the conservative side.
*Hi Jeff,Your right. Our building inspectors aren't that picky, and I'm glad they're not. You're absolutely correct.076 is slightly larger than a 1/16th...more like being 2.4 32nds. But since my inspector doesn't count splitting hairs, neither do I.Have a good one!!Davo
*The 4' sphere is the standard test. It does away with my opinion v. the inspectors opinion. No one needs to be picky.
*Take into consideration that the new IRC code book states that you are only required to have a guard rail if the deck height is 30" above the floor or below grade. That is when the spacing comes into play. So it might not be that the inspector is picky but the fact that some decks are not at the height that requires the 4" inch sphere to NOT be able to pass through the post.
*bigjim,It sounds like your saying that if code does not require a railing, then the balusters on a railing don't need to meet the 4" rule.Is that what you're saying? And are you sure about it?Seems to me that the 4" rule would apply whether the railing is necessary or not.But I don't have the code...Rich Beckman
*Common sense would seem to agree with Rich... it doesn't matter if it's required or not, they shouldn't be more than 4". I would be as concerned about a child poking their head through there and getting it stuck as I would them falling through.
baluster spacing
Take the longest opening between newel posts and make a story pole 6” longer (I like to use lattice, great for door jambs to transfer hinge pockets to the new door also). Lay out the balusters starting with a 4” space, baluster, 4”, etc. until out of story pole. Lay the story pole across the opening and even out the space at each end. If the space is less than 3” just knock off one of the balusters and make the openings at either end 4-1/2” or 5” wide. You can now use this story pole for all the openings doing the same thing.
Using it on a staircase you can do it last and cut it up as you move it up the stairs keeping it against the newel post. You can clamp a straight edge to the newel post and move it up till all the balusters are laid out.
Mike
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Somewhere I saw an article or letter-to-the-editor or on-line discussion about how to calculate spacing for deck handrail balusters. I searched the magazine index at FHB main site, but didn't find anything. Anybody remember the source?
Here's what we're going to do: There will be 4x4 posts about 6 ft apart, with 2x2 balusters between them with about 4" gap. I need to know how to calculate the actual spacing.
Here's what I do, you're welcome to try it.
Guesstimate how many pickets you will put in, lay that many down and measure the total width of them laying side by side. Subtract this dimension from the total width of the opening and divide the result by one more than the number of pickets you guesstimated (ie. if you picked 10 pickets divide by the 11 spaces you will create) The result is the spacing. If the resultant spacing is too small guesstimate fewer pickets and recalculate.
I then cut a spacer to the dimension I calculated and work in form both ends, when I get close to the middle I see how my layout is working, and, if necessary, increase or decrease the gap a tad to compensate.
Get the distance between your ends in inches and add the thickness of one baluster. Divide that amount by 4 (or whatever you max allowed center-to-center spacing is). If you get, say, 18.25, divide the distance by the next larger round number (19). That will give you the center-to-center spacing you need.
This is how I usually do it when I want equal spaces everywhere.
Yeah, that's what I said.
Deck hand rail spacing
Google spreadsheet for picket spacing there is one I use it's an excell spreadsheet . The authors last name starts with a K
saints be praised.
Thank you for that.
Spacing Calculator
Hello,
I have one good android application for you. This calculates all the spacing in a moment. You can either set the number of elements or the range of the gap you like. You get a solution also with the list of all the middles and edges.
Link: https://play.google.com/store/apps/details?id=com.sm.gapcounter