joist hangers and ceiling joists with drywall: notch? or no?

I plan on using Simpson joist hangers to attach my ceiling joists to a glue lam beam. These hangers will, no doubt, protrude beyond the plane of the bottom of the ceiling joists making the surface uneven. How are people dealing with this? I searched and couldn't find any definitive answers. I've found some mentions of people notching out their joists but I'd rather not damage the integrity of the ceiling members if they'll be carrying a considerable amout of weight (note: I'm talking about my inner layer here which I'd like to have 3 layers of 5/8" rock). I noticed in the old Dan Fitzpatrick thread that he attached some "shims" (not really sure if they qualify as proper shims here....hence the quotes) to the bottom of his joists but that seems kinda hacky not to mention somewhat risky. I suppose one could use really long screws (since they'd have to penetrate through the shim just to get to the joist) but, again, I'm not sure what's optimal in this regard. Thanks.

Usually that falls on the rock installer. What you don't want is to install a sheet at that hanger, the joint as it were. It would be better if a full sheet bridged the area, centered over the hanger area. But that might assume a textured ceiling which will hide a multitude of sin. Either way it works out, if you install the joists an 1/8 inch high and install the hangers at elevation OR the joists at elevation and the hangers below elevation, it is kinda us just being anal :) Float the beam with the rock, especially a 5/8 inch rock, it will not reveal the change as much as you might think.

Thanks for the response, xspace. Always appreciated. I'm not too sure what to take from it however (and that could very well be from the fact that I've had no coffee yet.....so I apologize if I seem a bit dense). From what I've been reading, this is the way to hang joists from a glue lam beam: My concern is with the 1/8 (or so) inch protrusion of the hanger. I could see how one layer of drywall might not pose a real problem but that issue could easily get exacerbated with multiple layers, no? Thanks again.

The issue is that you are looking at HVAC hangers[in the supplied picture] and that has nothing to do with what you started this topic with...joists and hanger...so my suggestion stands :) I have never, in my life, notched a joist for a hanger...if I would have I would have been fired at that time.:)

Gotcha on the notch. That's what I was having difficulty gleaning from your first post. So in regards to my posted image, I was assuming that the most efficient (and safe?) use of weight transference (if you're gonna use hangers) is indeed the one with the 'correct' caption....no matter what that weight may be. HVAC or joist. Having never seen 2x10 joists connected to a large (15+ inches) gluelam beam in real life, I have no good mental image of what this will look like (yet). Perhaps someone out there has numbers on what's been proven strongest. Maybe just lag bolts and a ledger board? Like a standard deck? It's the weight of the drywall that's concerning. Many thanks.

in my own home we simply put the joist/hangers on the upper portion of the beam and it's rock solid. the laminated beam isn't like normal wood where the grain is likely to split. here's some info that may be helpful. http://files.buildsite.com/dbderived-f/ ... 307573.pdf

Thanks gullfo. Since I'll be holding about 2600 lbs up there...... (1470 lbs of drywall, 889.68 lbs of 2x10s [<--that's actually using 16" oc but I'll probably be doing 24"], 130 lbs of lighting + cloud, 65 lbs of "spacer" wood. NOTE: I always round up :wink: ) ....I would feel most comfortable attaching to both the top and the sides of the gluelam beam. Something along these lines: I have yet to see a real picture of someone doing this, however.

Pure L wrote:

Gotcha on the notch. That's what I was having difficulty gleaning from your first post. So in regards to my posted image, I was assuming that the most efficient (and safe?) use of weight transference (if you're gonna use hangers) is indeed the one with the 'correct' caption....no matter what that weight may be. HVAC or joist. Having never seen 2x10 joists connected to a large (15+ inches) gluelam beam in real life, I have no good mental image of what this will look like (yet). Perhaps someone out there has numbers on what's been proven strongest. Maybe just lag bolts and a ledger board? Like a standard deck?

The HVAC hangers are deceiving in respect to what (you) we are trying to achieve. The installation of that specific hanger requires all-thread, maybe 3/8" so to install that on the bottom of anything really, short of a steel beam welded on, is asking for the material to go beyond what it is designed to do. Hangers for joists, wood I beams and the like are a different thing, have a different approach and can be placed anywhere in the field of a glu-lam that is specified. So you can install the joist/hangers at the top of the beam or you can install the same configuration at the bottom of the beam, rather the lower side. As I see that a post is made while I am doing this post, if you use a saddle type, then you have no options since it will only install as a "hanging" type hanger...different than just a hanger :) A considerable difference is the nails that you use to install the bracket. Since a glu-lam is a very dense product...your hanger manufacturer, Simpson assumed, will require a specific nail. Reason being is that it is a dense material and typical cement coated nails cannot be driven to seat into a glu-lam without bending.

Good point, Brien. I didn't even realize that about the weight just sitting on the threads of that bolt. So then in regards to the 'allowable loads' part of the Simpson pdfs, how is that being calculated? This is the pdf in question: http://www.icc-es.org/reports/pdf_files ... r-2549.pdf If you do a 'ctrl' + 'f' and search for 'hu210-2' you'll see what I'm looking at on page 5 near the middle of the document. (Side question: The huc210-2 is the one with 'concealed flanges'. What's the idea behind concealing the flanges?) From what I've read, the 'allowable loads' is the duration of load multiplied by a snow load (1.15) and by 1.25 for seven day loading. What seems odd is that I'd assume that this number would decrease in the table (e.g. the stress on the hanger is increased with the more weight put on it) since 1.00 being full time loading (i.e. the base loading) and if you put more weight on this (e.g. 1.00 x 1.15, etc.) then the allowable load that the hanger could take seems like it should go down, no? In the table it goes up.... Clearly I'm missing something. Either way though, are those numbers the total pounds that one hanger can stand before failure? If so, what's the best way to figure out the median number of pounds that each hanger will be holding? Divide the total pounds by total number of hangers?

Pure L wrote:

So then in regards to the 'allowable loads' part of the Simpson pdfs, how is that being calculated? This is the pdf in question: http://www.icc-es.org/reports/pdf_files ... r-2549.pdf If you do a 'ctrl' + 'f' and search for 'hu210-2' you'll see what I'm looking at on page 5 near the middle of the document. (Side question: The huc210-2 is the one with 'concealed flanges'. What's the idea behind concealing the flanges?) From what I've read, the 'allowable loads' is the duration of load multiplied by a snow load (1.15) and by 1.25 for seven day loading. What seems odd is that I'd assume that this number would decrease in the table (e.g. the stress on the hanger is increased with the more weight put on it) since 1.00 being full time loading (i.e. the base loading) and if you put more weight on this (e.g. 1.00 x 1.15, etc.) then the allowable load that the hanger could take seems like it should go down, no? In the table it goes up.... Clearly I'm missing something. Either way though, are those numbers the total pounds that one hanger can stand before failure? If so, what's the best way to figure out the median number of pounds that each hanger will be holding? Divide the total pounds by total number of hangers?

What the table represents is a tracking device for engineers who are in charge of making calculations based on what hanger is used, what material is the hanger being used on, what length, and for what specific purpose. Looking anywhere in the data you can see that the load increases with the increase in nail size, nails cannot be underestimated in framing. "since 1.00 being full time loading" Not being an engineer I am not even going to pretend that I can tell you what these numbers mean saving that 1.00 designates a floor, 1.15 >if< snow loading will be part of the equation, 1.25 if it is being in a roof, 1.60 if wind is part or maybe to what extent, and I assume that even all of that is dependent on live/dead loading of the overall project. There may also be safety factor fractions. To understand how much a hanger can withstand, I believe paragraph 3.2.1 explains that but refers to ASTM A 653 SS, which I would not, or rather do not have access to that document so do not know what that is as well :) The concealed flange hanger is in the document you linked, at the very end of the document. I assume in a rustic environment, this might be the hanger to use. These are documents for engineers...not me :)