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Residential Joists Drafting Standard 3

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GaStruct

Structural
May 20, 2024
24
How do you all show joists for residential projects? I gained the majority of my experience in CT and NY and around there everyone shows the joists as harpoons. I am now practicing in GA and I am seeing most "architectural designers" (ie: unlicensed architects playing architect)drawing each individual joist on plan. This is a headache to look at to me but I am finding out that many contractors down here just cannot understand how to read my legend and figure out which way the joists go. Now I'm not sure if I'm crazy or if they're illiterate.

Here's how I have been showing joists for years with a legend included on every plan. Again, no problems before moving to GA!

Capture_eccsjb.jpg


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I'm in SC and I do it like this, and include this legend on framing plans.

I've seen different arrows mean different things on so many plans. Some with just your 'harpoon' and no 'extents' arrow, and I'll have no clue which way they're supposed to be going, so I get why contractors would get confused.

legend_pc6fxo.png


example_cco13b.png
 
I don't like the "harpoon" method. It seems confusing. Plans should always be as clear as possible.

My approach is either:
[ol 1]
[li]Draw every joist (which makes sense if the framing is complicated/non-uniform), or [/li]
[li]Draw a few joists and note that the framing repeats beyond. This is far superior to the "harpoon" approach, in my opinion, as there shouldn't be any confusion in terms of which way the joist is spanning. See the image below for a roof plan I recently completed using this approach for the roof rafters.[/li]
[/ol]
roof_framing_continued_rqtd27.jpg
 
I draw every joists and on the page I say All joists are XXXXX @ 16" o.c. U.N.O. Then if I have different joist type or different spacing, I label it on the drawing.
 
TheDW - what is with those odd ninety degree jogs in that arrow, what is that accomplishing? Why do two arrows meet in the middle of nowhere? The spans are the same.

I'm in the midwest, say.

To me drawing every joists creates a lot of clutter, but it does clearly establish the span direction. The harpoon is less clutter, but the bearing point ... you might just add a plan note there calling it a bearing point, so people don't have to refer to the legend. I inherited somebody's way of drawing this so the bearing locations get a double headed arrow.

Maybe architectural graphic standards has something?
 
Its not really relevant but the unpictured joists are in the kitchen with granite countertops all over the place, so they have a tighter spacing.

I like the jog to differentiate between the 'joist' line which is always straight, and its location arrows...I feel like 2 straight lines could have someone mistake which line is indicating joist and which is indicating location. If it gets too cluttered I don't do the jog
 
I would also in a perfect world prefer to show every joist.
 
I draw all the joists and use a straight line indicator. I often schedule the joists so the callout will say something like 'J1' rather than '16 TJI 360 @ 16" o.c.' to keep the plan somewhat cleaner.

I use a different linework for joists than beams as well.
 
For me, it varies form job to job. A small addition? I'll draw all the joists/rafters. A large, custom home with complex framing, transfer girders, weird uplift load paths, and impossible roofs? I use the "harpoon" method (never heard it called that - I like it) because if I don't, you can't read my plans. I'm in Virginia, so about halfway between NJ and GA. So I guess it's fitting that both work here...
 
Thanks for the replies all. I do agree that drawing each individual joist does make the intent of the joist framing more obvious. However, I don't do it for two reasons:

1. It takes too much time
2. It makes the plan too crowded and distracts from all the other important information I put on plan

I am thinking I will just make my harpoon symbol a thicker and darker line so it stands out more than the extent arrows.

 
The span direction is obvious in the OP due to the layout, but if it were a square bay with the two arrow types I honestly wouldn't be 100% confident in which direction is intended, even with the legend. I would probably have to dig through the plan to find an obvious location like pictured to confirm that I understand the legend correctly. Maybe I'm just too used to my own style.
 
I am working with architects who use ArchiCAD and they model every joist and beam in 3D. This is then transferred to a framing plan. The framing plan even shows the width of the framing members. I don't like it. I review their plans and structure, trying to make it as readable as I can for the builder. They stamp it not me.

I have had no issues using a similar notation as GA Strut but I am also from the Northeast.
 
I suppose on smaller projects you're not likely to get a shop drawing, but you can still require it.

There's a difference (when there are supposed to be shop drawings) for wood joists versus anything else (I joist and trusses could have a shop drawing requirement on the project).

What about, instead of the harpoon, show one actual (wood) joist, and then show the extents perpendicular, with the fallout giving size and or spacing (or a coded key note)?
 
Harpoon here. I use the extent arrows sometimes, but not typically. I haven't gotten any questions from a builder about what either indicates (yet).

That said, I DID catch flack from a fellow EIT 3 years ago when I kicked back a draft set of plans where he put the harpoon the opposite way of the span. Simple fix and I was clearly correct per the industry standard, but WOW he got upset and told me "I don't care, that's stupid and I'm not doing it that way." I think it was because he was 20+ years older than me, but I was reviewing his projects where he made mind-blowing mistakes regularly in analysis and design. Weird dude--terrible engineer. Fired after 4 months for screaming at our office manager.
 
RPGs said:
I haven't gotten any questions from a builder about what either indicates (yet).

I don't think I've ever had someone reach out deliberately with the question either but I occasionally get truss shops where it was obviously not understood, and have had to review already constructed stick framing occasionally that was also installed by someone that did not understand.

I only added the framing sketch from my first comment to all of my plans this past year after a framer I was on site with for different issues just asked why I showed the ceiling joists going a different direction than they usually would have been (he thought it was going the opposite of what my actual intent was). I feel like unless we put every single piece of wood on the plan then there is always going to be someone that will do it backwards.
 
I do not like the harpoon approach, I find it confusing, particularly on multi-family projects where framing can change direction multiple times within a single section of a structure. I prefer showing several joists with the direction and joist callout, with the floor sheathing thickness/grade showing as well as the diaphragm nailing and blocking requirements in this area of framing. I will use something similar to the standard details in SDPWS, but indicating the notes above.

Capture-1_oto1ny.png
 
Harpoon shows joist direction, arrows show extents. For nice uniform cases this is all we show. I've never had issues where I work showing it like this. We don't even provide a legend for this, it's just the notation.

If the joist situation is a bit more complicated and changes direction, or if it is a bit more unclear, we draw in the joists on a lighter layer, but don't necessarily call them up (Similar to what TheDW showed just without the "Joist" call-ups).
 
I usually prefer not to draw every joist like a kindergartener... just kidding everyone... please don't start throwing things... ;)

Seriously though GaStruct, I am GA also, and my early career was large scale commercial projects (multi-family, retail, high-rise, etc.) working at large firms. It has been my experience that commercial projects are less likely to draw every joist. Now as a small shop I see more single family residential drawings and more plans that show every joist. I find the drawings annoying and headache inducing to look at with all the joist shown. The wanna be architects that you mention are some of the worst offenders.
 
I have a plot style and make the joists light, and the beam thick and dark. I can put text over the joists no problem. It is not cluttered at all.
 
DoubleStud said:
I have a plot style and make the joists light, and the beam thick and dark.

If you're going to show joists, it has to be done this way. Reading text is a nightmare if every lineweight is the same.
 
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