# How much weight can a stud hold?



## nitrochilled (Mar 13, 2017)

I'm trying to find out how much weight a stud can hold. The studs are 2x4 correctly built into my home (or so i hope...) Assuming the mounted objects are mounted to the the stud with a mount that has the height to width ration correct and equal to the weight and directional pull of the object being mounted. 

so basically the object is being mounted 100% correct. so assume this is not the factor. only an omni-dimensional object of infinitely altering weight is being connected to a stud. how much weight or pull could the stud withhold before breaking free of the truss or floor, or splitting in half or something

i know this sounds ridiculous but i am almost daily mounting things to the walls. something i never thought of previously in my years of varying construction trades or other home lives. here though in my home i mostly practice my new trade and its come to grab my attention that 2k lbs mounted to my wall might not be a good idea. or 100 lb projector screen mounted lengthwise along the living room truss. the most free running unsupported one in the house i think. except the garage. or a 100+lb ceiling or high wall mounted subwoofer and speaker stack. 

i don't mean to sound cryptic or confusing, i am just trying to learn maybe a good formula i can use to be safe. i can get bigger mounts to more evenly distribute weight, that isn't the issue. i have mounted MANY things so far and damn near hung from all of them. actually i did hang from my projector screen mounts. 

i like to be analytical and correct structurally. i hope this makes sense as it was a lot to wright! 


last add! its like towing a car. how much engine power is required to pull a vehicle. ignore the size and weight of both vehicles and ignore the media connecting them. only the ratio of say, horsepower and torque to resistance.


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## abrowning (Jun 2, 2008)

Guess you need an engineer to answer this. I'm wondering what an "Omni-dimensional object of infinitely altering weight" is though. 

Is that just another way of asking for a general equation to handle several variables?


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## Clutchcargo (Mar 31, 2007)

SPF 1100 lbs/in^2
DougFir 900 lbs/in^2
The problem is supporting it so that you can put that weight on it without it buckling.


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## nitrochilled (Mar 13, 2017)

Yes it is. i liked phrasing it like that though! essentially its an object "x" could be straight out from the wall or straight up and down. sideways. heavy, light. anything. just wanting to know a studs maximum limit.


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## nitrochilled (Mar 13, 2017)

so basically DF could hold 225lbs with only a 2x2 mount?


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## nitrochilled (Mar 13, 2017)

I replied in the wrong spot accidentally.

basically a DF could hold 225 with only a 2x2 area mount?


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## Bondo (Dec 8, 2007)

Ayuh,... Yer question is pretty much Unanswerable,...

A 2x4 in a wall is part of a system, all of which adds to the overall strength,...
Yer not hangin' anything on a single stud standin' by itself,...

In my experience, it would hold whatever weight, til the fastener you use breaks off,.....


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## Bud9051 (Nov 11, 2015)

"i know this sounds ridiculous" your words not mine.
There is no answer to the question you are asking as Bondo replied, consider how many fasteners are holding that stud in place. Consider, was that an average quality stud for the specifications you might reference or should it have been culled out by the framer.

Good judgement and over kill on your install will be better than over analyzing.
PS, shift, SHIFT, shift, easier to read!

Bud


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## ChuckF. (Aug 25, 2013)

Your question might be easier to answer if the stud was assumed to be planted securely and you were asking how much weight you can stack onto the top of the end. That would be a pure-compression geometry. That's not a practical arrangement though. 

Whatever you 'hang' on the stud will be out in front of it, maybe on some kind of bracket which introduces a torque on the stud, in other words it's no longer simply being compressed, you are now trying to bend it. That makes the length, bottom, top, and sheathing and all related fastening and how high up, all critical parts of the geometry.

If you drew a picture of what you want, one of the real engineers that stop by regularly might be able to hazard a back of the envelope calculation.


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## clarenceboddick (Nov 30, 2016)

Not every stud is the same due to differences like knots, cracks from drying, etc. Besides the load, how that load is attached to the stud can make a big difference. How stressed is the stud currently? I'd say if you're in doubt add a plate that ties into a few studs and mount your object to that.

I suppose you could make a test fixture and run a few destructive tests. You'd have to anchor and preload the stud you're going to test to failure and have a way to measure the load and deflection over time.


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## Daniel Holzman (Mar 10, 2009)

A stud is a vertical element. There are two primary modes of failure for a vertical element in pure compression. The stud could fail due to compressive failure of the wood. This is the mode of failure for very short studs, think one or two feet long (cripples). A standard stud of length approximately 8 feet would almost certainly fail in buckling, which is a more complex failure mode than compression.

I am not going to present the Euler theory of buckling, that is taught in a second year college mechanics of material course. I will point out that the ultimate buckling load of a column (a stud) decreases the further the load center is away from the centroid of the stud. So the further offset the load, the lower the strength of the stud in buckling. The longer the stud, the lower the buckling load. And failure becomes even more complex if the stud is loaded in a combination of bending and compression, which would occur if the load is off center.

Computing buckling capacity of a column is an advanced problem in mechanics. I do not recommend calculating the ultimate load by adding load until the stud fails, buckling can occur suddenly and explosively, very dangerous.


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## abrowning (Jun 2, 2008)

OP. With the weight you have on your walls now are they exhibiting any bowing? Any cracking of drywall seams or popping of screws or nails? Any separation of trim from walls? I think good practices are your best friend here. Use horizontal members attached to multiple studs to distribute load. When large heavy items are on shelves use auxiliary legs to support the fronts of the shelves.


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## ront02769 (Nov 28, 2008)

Put aside the speakers and stuff and consider your kitchen cabinets......which get filled with hundreds of pounds of dishes, serving platters, etc. ever see a wall crumble due to same?


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