Also would it be wise to do as the earlier poster described and design off the 8ft span from the lbw wall to the end of the mezzanine when calculating my point loads for the reinforced truss/ trusses. Despite the fact that i will be running continuous 16ft floor joists
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Suspended mezzanine
- Thread starter Jking24
- Start date
Just gives a little more margin. Most design is limited by deflection. The engineer wants the floor to not be too springy. We don't want the structure to collapse either. But, generally if the design becomes inadequate, it's too flexible before it's too weak.
sberry
Banned
If a guy was using cables doesn't mean one needs to be exactly in the center but,,, would skip all that point loading with a different design. Secondly, same in my own but a guy can put any real loads over a bearing wall, doesn't need to stack bricks and engine blocks out on the overhang.
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Thankyou cmc and you are correct about the snow loads.i am right on the line where they move from 25 psf to 35 psf in my area but i am technically below the line. Despite the many criticisms here about my idea. I let that 40 psf ride because a. I figured it allowed for a greater safety margin witch many have stated i clearly don't care about . B. i don't claim to be a very educated person but I'm smart enough to figure out how somebody came to a given number. I will be deciding on the vendor for my lumber this weekend so after that i will be able to speak with the truss company. From the looks of your calcs those numbers are for running 3 cables across the span and using just one reinforced truss ? I only asked to get a better understanding because 1/4" plate 3" tall is pretty hefty .
I think you need to define the live load on the mezz. 40psf would be 'very light' storage, 60-80 would be moderate, and code for storage mezz would be 100psf. Its not the snow load, etc for the area that you are in.
I understand that it's not the snow loads.i was referring to the original truss discussion when i referenced that not the floor. I believe i may have misread the code though because i thought it said 40 for my intended use. I do not currently plan to store much up their in regard to weight. Mostly large bulky items . But we all know that may change over time and with time comes added clutter ie. weight. I will recheck my local code but if you say 100psf is the appropriate number than that's the number i will use. I did not know a lvl could be used with joists hangers and the difference in height going up creating a pony wall. I have no problems with anything extending up from the floor of the mezzanine as it will likely have a railing or wall anyway. could a girder truss be used in the same manner with joists hangers on the bottom cord and the remining portion up? I believe another poster may have mentioned this but i didn't quite understand what he meant at first.I think you need to define the live load on the mezz. 40psf would be 'very light' storage, 60-80 would be moderate, and code for storage mezz would be 100psf. Its not the snow load, etc for the area that you are in.
Now clearly I'm not a engineer but 100psf seems really high. If i understand it correctly and i probably don't. Is that saying my entire mezzanine 16x40 could hold 64000 lbs that seems like a bit of over kill. Please educate me on the dynamics i am missing. Because while it would be nice i don't plan on keeping my motorhome and truck up their lol
Ground snowload - 25 psf115 MPH wind speedAttics with storage - 20 psfDecks - 40 psfBalconies - 40 psfRooms (other than sleeping) - 40 psfSleeping areas - 30 psfPassenger vehicle garages - 50 psf (2000 lb point load over 20 sq. in area)Handrails - 200 lb concentrated lateral loadSoil bearing capacity - 2,000 psf
That didn't copy and paste very well but this is what my local code says for design loads
That didn't copy and paste very well but this is what my local code says for design loads
I understand that it's not the snow loads.i was referring to the original truss discussion when i referenced that not the floor. I believe i may have misread the code though because i thought it said 40 for my intended use. I do not currently plan to store much up their in regard to weight. Mostly large bulky items . But we all know that may change over time and with time comes added clutter ie. weight. I will recheck my local code but if you say 100psf is the appropriate number than that's the number i will use. I did not know a lvl could be used with joists hangers and the difference in height going up creating a pony wall. I have no problems with anything extending up from the floor of the mezzanine as it will likely have a railing or wall anyway. could a girder truss be used in the same manner with joists hangers on the bottom cord and the remining portion up? I believe another poster may have mentioned this but i didn't quite understand what he meant at first.I think you need to define the live load on the mezz. 40psf would be 'very light' storage, 60-80 would be moderate, and code for storage mezz would be 100psf. Its not the snow load, etc for the area that you are in.
sberry
Banned
I think Ironcrow and I were refering to the same general idea and assumed there would be a wall to allow sheeting. This could spread the load.
Seems that a lot of engineers are being ignored. You can work with truss manufacture to have a truss that is "special" for the loads. For purpose of permit that you are pulling that would fall into the category of overbuilding and the inspector probably won't call you on it as long as that special truss has its own drawing stamped.
If this was mine and was going to do something like described I would design for that special truss to cover the span all the way back to the exterior wall and not make the intermediate rooms wall a load bearing wall maintaining future flexibility to the maximum. Floor joist have to get a bit deeper but small add for possibility of getting all of the lower level post free.
Trusses in most cases the members are either tension or compression - not intended for bending loads. Attic Trusses don't fall into that but they are more the exception than the rule. IOW - cables or randomly attached hangy downy things to tie to the floor probably are a very bad idea.
If this was mine and was going to do something like described I would design for that special truss to cover the span all the way back to the exterior wall and not make the intermediate rooms wall a load bearing wall maintaining future flexibility to the maximum. Floor joist have to get a bit deeper but small add for possibility of getting all of the lower level post free.
Trusses in most cases the members are either tension or compression - not intended for bending loads. Attic Trusses don't fall into that but they are more the exception than the rule. IOW - cables or randomly attached hangy downy things to tie to the floor probably are a very bad idea.
Seems that a lot of engineers are being ignored. You can work with truss manufacture to have a truss that is "special" for the loads. For purpose of permit that you are pulling that would fall into the category of overbuilding and the inspector probably won't call you on it as long as that special truss has its own drawing stamped.
If this was mine and was going to do something like described I would design for that special truss to cover the span all the way back to the exterior wall and not make the intermediate rooms wall a load bearing wall maintaining future flexibility to the maximum. Floor joist have to get a bit deeper but small add for possibility of getting all of the lower level post free.
Trusses in most cases the members are either tension or compression - not intended for bending loads. Attic Trusses don't fall into that but they are more the exception than the rule. IOW - cables or randomly attached hangy downy things to tie to the floor probably are a very bad idea.
No engineers are being ignored here. Many are assuming that i am set on doing somthing very bad In their mind so they start tearing the idea apart before ever actually considering what I've asked and i stated in the beginning it was an idea i also stated that i didn't yet have a truss manufacturer so when i choose my supplier i will speak with them about the project. Im not sure i understand what you are suggesting this is a 16x40' mezzanine in a 40x60 building spanning the whole 40 ft of one side of the building from the font wall to the back. My trusses are running the 40' span and so will this load bearing wall set at 8ft from the side wall of the building (same direction as trusses). It will be installed regardless of the mezzanine size or existence and i don't ever see it being removed for any reason. If I'm not understanding what your suggesting please elaborate I'm open to all suggestions. Despite the criticisms i would like to build this as safe and as efficient as possible.
I understand that it's not the snow loads.i was referring to the original truss discussion when i referenced that not the floor. I believe i may have misread the code though because i thought it said 40 for my intended use. I do not currently plan to store much up their in regard to weight. Mostly large bulky items . But we all know that may change over time and with time comes added clutter ie. weight. I will recheck my local code but if you say 100psf is the appropriate number than that's the number i will use. I did not know a lvl could be used with joists hangers and the difference in height going up creating a pony wall. I have no problems with anything extending up from the floor of the mezzanine as it will likely have a railing or wall anyway. could a girder truss be used in the same manner with joists hangers on the bottom cord and the remining portion up? I believe another poster may have mentioned this but i didn't quite understand what he meant at first.
Its your call, Actually light storage for a commercial building is 125, assembly areas is 100. This is based on ASCE-10. I would stick with your 40 and just be cognizant of what is stored. If you sell, put a sign up for what its designed.
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