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Discussion Starter · #1 ·
I'm building a medium-sized entertainment center and hoping to hang it on an exterior wall of my house, using brackets made by Rakks. I've been adding up the total weight and it seems like, including LPs, the TV and the shelves, it might be as much as 450 lbs. I'm wondering if this is too much.

The house was built in 1946 and has real plaster over studs. (The wood itself seems considerably denser than what you would buy today. Hard to get screws in.) All support brackets will be anchored into studs -- every 16". The whole thing will be 4-6 feet wide (some shelves are wider, some are narrower). Bottom shelf will have 4' of LPs (heavy), top shelves will have 6' of CDs (lighter). Two other shelves will have DVD, receiver, etc. Flat screen TV will be about 50-80 lbs.

I've got other shelf units in the house that are probably holding as much as 300 lbs, maybe more, also attached to studs, and they seem fine.

The brackets I'm using are supposed to be strong enough. I'm wondering about the wall itself.

Many thanks to anybody who has any thoughts or suggestions about this!
 

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450 lbs..... that's two people my size... scary thought. I am not a structural engineer but to me, that is a lot of weight for wall studs. A house built in '46 probably had older growth lumber used, but over time it has dried out more, which would cause it to be more brittle. That's not a big deal as is because the weight it is supporting is straight down. Once you start adding that much weight that pulls laterally ...I don't know. Guess it may depend on how many studs are sharing the load.
 

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Discussion Starter · #5 ·
4 or 6 studs depending on which shelf is involved. No less than 4.

The only heavy shelf is the bottom -- 16" with the LPs.

Basically the same as two big guys doing pull ups on a bar attached to the wall. I've got 300 lbs on other walls and they seem fine.

But I take your point. I can put legs under the bottom shelf. Just seems inelegant.
 

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450 lbs isn't that much spread out over 6 ft and say 4 anchors, the weight distribution is only about 112 lbs per anchor. Get your anchors solidly in studs and you should be ok.
 

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4 or 6 studs depending on which shelf is involved. No less than 4.

The only heavy shelf is the bottom -- 16" with the LPs.

Basically the same as two big guys doing pull ups on a bar attached to the wall. I've got 300 lbs on other walls and they seem fine.

But I take your point. I can put legs under the bottom shelf. Just seems inelegant.
Having the really heavy weight toward the bottom would help a lot. You could have a couple of guys doing pull ups on a wall with that weight with no problem. The problem is they wouldn't be doing pull ups 24/7 for years. It's as much horizontal weight as anything. It's like you took a chair and cut the front legs off. There would be a lot of weight pulling horizontally. It may work and it might not. A lot depends on the strength left in the studs and if they are well fastened to the top and bottom plates. It would work in my parents house. The studs are a full 2"x4" and made of poplar. Another house especially if the studs had large knots or dry rot the studs might break in two. There is just no way to really answer your question. You would have to take the lath and plaster off the wall to really determine the structure of the wall.
 

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The weight will be applying pressure to where the anchor/screw would have to shear off. Shear strength of a screw is the strongest.

Take 24" wide cabinets 36 in high made of 3/4" plywood, 3/4" shelves and loaded with dishes. You would probably have the same weight as he is talking about spread over the same distance.

The key is get the screws far enough into the studs so that it is solidly mounted. Use at least 4 screws and it should be fine. If you can get 4 on top and 4 on the bottom it's better. If you can mount it with on long cleat probably better. Two long cleats even better.
 

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What matters more so than how much weight you've got hanging on the wall, is how far out from the wall it's hanging. I'm thinking that you're talking about 1 foot deep shelving, or similar. In that case, just make sure you anchor into the studs and you'll be fine. That's not a major lateral force; it's all right up against the wall. If you want 4 feet deep shelves with the weight at the edge of the shelf, that's a different story.
 

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450 lbs isn't that much spread out over 6 ft and say 4 anchors, the weight distribution is only about 112 lbs per anchor. Get your anchors solidly in studs and you should be ok.

Totally agree. Put legs under the bottom shelf would be good if the cantilevered load sticks out far.

GEorge
 

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Discussion Starter · #11 ·
Wow, thanks guys -- that's super helpful.

The lower shelves, below the TV, are the deepest. 16". The biggest weight down there is the LPs, at the bottom. They are 12" deep and will be centered on the shelf. (There are really two shelf units, upper & lower with two sets of brackets. The TV sits in the middle hanging on a wall mount.)

The brackets are designed for #6 screws and apparently can't be modified for bigger ones. I wanted to use bigger screws, but the company that makes them has reviewed my drawings and thinks they are okay. (They also pointed to the top screw as the key issue.) I'm planning to use 2.5" screws. Brackets are 1/2", plaster is 3/4", so they'll be 1.25" into the wood. Could go to 3" if you think it would help.

Picture of brackets is linked below. They're aluminum.
http://rakks.com/portfolio/PopUp/tstyle.html

Thanks for all the help --
Steve
 

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I thought you were building a shelf unit as an entertainment center. Your using a adjustable shelf system. I'm not familiar with nor does it show how the brackets stay in place. However your going to have 3-4 screws per upright and should have 3-4 latter being better uprights all mounted into studs.#6 screws will work but make sure they are long enough to go 1 1/2" -2" into the stud. Real plaster walls generally have slats over studs for the plaster to adhere to. The slats are generally 1/4"-3/8" thick with 3/8" - 1/2" of plaster depending on who the plasterer was and how straight the wall was.


As for the long cleat, I should have said French cleat. However that don't matter since your not building this entertainment center.
 

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Discussion Starter · #14 ·
Okay, got it. Many thanks. Sorry I wasn't clear. The walls don't have wooden lath. Two layers of 1/4" plaster, one on a cardboard foundation. But in any event, I'll use 3" screws. The brackets are rated for 50-100 lbs each. (I am using different sizes on different shelves.) Manufacturer says they are strong enough.

What did you mean by "your going to have 3-4 screws per upright and should have 3-4 latter being better uprights"
 

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Each bar or tract that the brackets are on should have several screws to hold it. The whole concept is weight distribution.
 

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Wow, thanks guys -- that's super helpful.

The lower shelves, below the TV, are the deepest. 16". The biggest weight down there is the LPs, at the bottom. They are 12" deep and will be centered on the shelf. (There are really two shelf units, upper & lower with two sets of brackets. The TV sits in the middle hanging on a wall mount.)

The brackets are designed for #6 screws and apparently can't be modified for bigger ones. I wanted to use bigger screws, but the company that makes them has reviewed my drawings and thinks they are okay. (They also pointed to the top screw as the key issue.) I'm planning to use 2.5" screws. Brackets are 1/2", plaster is 3/4", so they'll be 1.25" into the wood. Could go to 3" if you think it would help.

Picture of brackets is linked below. They're aluminum.
http://rakks.com/portfolio/PopUp/tstyle.html

Thanks for all the help --
Steve
I really don't like the idea of #6 screws that long. I would ream out the holes and countersink accordingly, and use #8. For support for the bottom that would be relatively not that obvious, you could make a clear Plexiglas box or display that would help support the bottom shelf.






.
 

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Discussion Starter · #18 ·
The people that make them (Rakks) say that because of the way the standards are designed, you can't get the head of a #8 screw in there. Actually, one problem is that the studs are very dense and in the past, I've usually had to soap any screw that goes in that deep. (Is that something you guys have a bad opinion of?) I can use different supports, but they don't look as good and they're not as adjustable -- but they'd be steel and I could use bigger screws. These also allow you to put the supports at any height, so installation of the verticals (the 'standards') doesn't have to be as precise.

As for legs, I am starting to think that the bottom shelf needs a couple of legs with levelers.
 
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