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Lunatique
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PostPosted: Tue Sep 02, 2008 12:48 am Reply with quoteBack to top

Rod- Mason in Shanghai finally got back to me, and they basically just sent me this PDF of their recommended products. I asked about the various models in each product line, and they said just pick the model that seems to fit your weight requirements. This is the PDF they sent me:
http://www.ethereality.info/ethereality_website/about_me/images/workspace/cloud_pagoda/construction/design/mason1.pdf

They wouldn't tell me the pricing though, as they said I'd need to tell them how many of what I need before they could tell me the pricing. They also said that usually unless you order more than $10,000 worth of products, there will be no bulk discount. I think I may be able to negotiate with them a bit though--we'll see.

I did some more drawings trying to work in the advice that you've given me over email and also here:

Image

The Mason PDF says to use the sway braces at 4' apart, and based on your previous recommendations I would space them 8' apart (since the ceiling will rest on the walls). But let's say hypothetically that a wall is 15' long--do you just place one sway brace at the middle of the wall (assume the ends of the walls wouldn't need any bracing since it's connected to another wall)? Or, you'd use two braces and divide their positions so that they divide the wall into 3rd's (but then the spacing wouldn't be 8' anymore)?

Image

That's me trying to figure out how to actually divide up the studs for the ceiling, and where to put the braces and hangers. Don't know if I got it right based on your suggestions.

The ceiling studs I divided to go length wise because if I did it by width of the room, those annoying ceiling beams would divide two of the quadrants into very short studs--I don't think that's a good thing if I want to try to make the 4 quadrants more "equal"? I added a center stud (in pink ink) since I wasn't sure if the length of those studs are too long and needs a crossing one to secure them together. Should I keep that pink stud or get rid of it?

On the top right corner you can see how I tried to gain back some space but still make the room symmetrical. Does that look ok to you?

If you see anything else alarming in my drawings, please let me know.
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PostPosted: Tue Sep 02, 2008 11:31 pm Reply with quoteBack to top

I just realized I had one more question regarding resting the weight of the ceiling on the new walls:
Image

Originally I was going to set the ceiling joists on the new walls just like the picture, but what stopped me was seeing some of your drawings showing this kind of a placement (the red). I have no idea what that does so I'm asking you what that's all about:
Image

Rod - I realize you're really busy, and I've been holding back on the construction to make sure that I'm definitely getting things right before I go any further. The thing is, the rest of our home is now nearing completion, and if I don't get started on the studio, it's going to be a lot more complicated later trying to live in that place and construct the studio at the same time. If you could please spend just a little more time to take a look at the current issues (they're really just the very last remaining ones--no more after), I'd really appreciate it.
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PostPosted: Wed Sep 03, 2008 10:21 pm Reply with quoteBack to top

OK - the studs on the wall are correct -

the hangers for the ceiling joist (They are not studs - learn not to call them that because it get's confusing cometimes LOL) are fine with a center support only - they will not need the stiffener.

You have miss-oriented the WIC brackets - they will not work the way you show them being installed - look in the book for details with the correct orientation.

The should be allowed to flex in their length - not the width or thickness.

You will need a detail similar to th bottom one for the walls that the ceiling joist do NOT bear on - the ones they run parallel to -

I really like to see the sway braces towards each end f any substantial wall (which I define as any wall greater than 4' in length.

The 8' spacing is not a magic number - it is a maximum spacing -

So for a 15' wall you should have 3 braces.....

for an 8' wall 2 -

with the braces within 2' of the corners the max wall you can do with 2 braces would be about 12' - and that's really pushing the outside edge......

It looks to me like you should have about 14 of the WIC clips.

Does that cover everything?

Rod

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PostPosted: Thu Sep 04, 2008 8:02 am Reply with quoteBack to top

Yay, Rod returns!

(Yeah, I looked up the definitions for studs and joists, and boy am I embarrassed.)

I think I need to consolidate my questions into one post, with numbering, so there's no confusion which question or drawing you are actually answering to. I'm going to post all the remaining issues below, with accompanying images and everything numbered, so it would be like a checklist of outstanding issues (I'm hoping and praying that these really are the final questions, and the next time I post, it'll be photos of the studio being finished).

The first few questions will be referring to this new image:
Image

1) Just fix the ceiling joists on the new walls and that's it?

2) One isolation hanger per joist, placed at the opposite end from the end that sits on the new wall?

3) Don't need to do anything special for the rest of the ceiling joist's length?

4) Sway brace orientation corrects. Is it correct now?

5) Since none of the walls seem to go over 12', it appears I might only need 12 sway braces? (I have two additional ones in orange color, and I'm not sure if I really need them.)

6) The width support joists (in pink)--please take a look at how I've placed them. I basically followed the same method as the length ones (in red)--one end held up with an isolation hanger, the other end placed on the wall. I've numbered each of the pink joists, so it's easier for you to tell me which ones I should keep or get rid of.

Note that #2, 3, 5, and 6 do not touch the walls, as they actually drop below the length beams in order to allow the gypsums to cover the existing width ceiling beam.

7) (Reffering to the image below) Is this new design to get a symmetrical room ok (how I joined the two walls at the corner)?

Image

8 ) What is a stiffener? (which part of which image were you referring to?)

9) (Referring to image below) So this is not necessary (the red)?

Image

10) (Referring the first image at the top of this page) I had drawn a center sway brace holding the wall to the ceiling (one per wall, placed in the center of the wall). I'm guessing that's not necessary either?

11) Could you please clarify this comment (sorry, I can be a bit dense sometimes):

Rod Gervais wrote:
You will need a detail similar to th bottom one for the walls that the ceiling joist do NOT bear on - the ones they run parallel to -


Whew. I think that's it for now. As soon as these outstanding issues are cleared up, I can order all the material and finally finish the damn thing. Very Happy
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PostPosted: Thu Sep 04, 2008 5:32 pm Reply with quoteBack to top

Quote:
1) Just fix the ceiling joists on the new walls and that's it?


Yes - but don't forget that you want to crate a fire stop between the inner gap of the existing wall and the new wall at the top of the new wall.

Quote:
2) One isolation hanger per joist, placed at the opposite end from the end that sits on the new wall?


What you have in your drawing if vine - which is the short joist sitting on the wall with one hanger at the opposite end - for the long joist it is on the wall and then a hanger at one end and one in the middle.

Don't forget that you have to size the hangers for the appropriate weight they will be carrying (as I said earlier - the Mason hangers are color coded so they can't get screwed up.

Quote:
3) Don't need to do anything special for the rest of the ceiling joist's length?


Nope - the are basically hung so that once loaded with the drywall they cannnot roll over.


Quote:
4) Sway brace orientation corrects. Is it correct now?


yup

5) Since none of the walls seem to go over 12', it appears I might only need 12 sway braces? (I have two additional ones in orange color, and I'm not sure if I really need them.)


Quote:
6) The width support joists (in pink)--please take a look at how I've placed them. I basically followed the same method as the length ones (in red)--one end held up with an isolation hanger, the other end placed on the wall. I've numbered each of the pink joists, so it's easier for you to tell me which ones I should keep or get rid of.


I do not understand why you feel you need these - just hang the hangers directly from the concrete deck above.

Quote:
Note that #2, 3, 5, and 6 do not touch the walls, as they actually drop below the length beams in order to allow the gypsums to cover the existing width ceiling beam.


this I did not understand at all - draw me a section thru the existing beams so I can see what you are tryng to say.

Quote:
7) (Reffering to the image below) Is this new design to get a symmetrical room ok (how I joined the two walls at the corner)?



This looks fine.


8 ) What is a stiffener? (which part of which image were you referring to?)

9) (Referring to image below) So this is not necessary (the red)?


10) (Referring the first image at the top of this page) I had drawn a center sway brace holding the wall to the ceiling (one per wall, placed in the center of the wall). I'm guessing that's not necessary either?

11) Could you please clarify this comment (sorry, I can be a bit dense sometimes):

Rod Gervais wrote:
You will need a detail similar to th bottom one for the walls that the ceiling joist do NOT bear on - the ones they run parallel to -


Look at the ceiling joist - now look at the walls to the left anf righ that run parallel to them- the detail you have is the way you need to carry the ceilng at those walls.


good luck

Rod

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PostPosted: Thu Sep 04, 2008 10:05 pm Reply with quoteBack to top

Quote:
don't forget that you want to crate a fire stop between the inner gap of the existing wall and the new wall at the top of the new wall.


I'll look into it, but AFAIK, China's fire safety code is pretty...um, you know. I have a feeling my contractor might get that blank look on his face when I ask him about it.

Quote:
Don't forget that you have to size the hangers for the appropriate weight they will be carrying (as I said earlier - the Mason hangers are color coded so they can't get screwed up.


Yep. I'm trying to get help from someone here to calculate the weight distribution, and this guy is very annoyed at me because he says it's a bunch of BS and no one bothers with that crap in China (the idea that the center and the edges of a ceiling do not impart the same weight, and the walls also have parts that will impart more weight due to the door frame and other things...etc).

Quote:
I do not understand why you feel you need these - just hang the hangers directly from the concrete deck above.


I had envisioned the width joists (pink) intersecting the length joists (red)
because I thought it'll prevent the length joists from moving side-to-side. It's great to hear that I don't need them (less ceiling weight to deal with).

Quote:
this I did not understand at all - draw me a section thru the existing beams so I can see what you are tryng to say.


It's basically the width joists (orange) in this image (though that image is old and need to be updated with the hangers and the orange joists should be rotated so they are laying flat):
Image

I figured I need to have two width joists (orange) drop below the length joists (blue) so I can wrap the gypsum around the ceiling support beam. I realize my drawing showing those two width joists split into 4 parts (the pink ones numbered 2,3,5,6) is unnecessary--they don't need to be split like that (when I drew that I forgot the two width joists actually drop below the length joists and do not intersect them like I had drawn).

Quote:
Look at the ceiling joist - now look at the walls to the left anf righ that run parallel to them- the detail you have is the way you need to carry the ceilng at those walls.


Ok, I think I understand now (I hope). You meant that this image:
Image

The red--that is the detail you're talking about. That is how the walls parallel to the length ceiling joists should look. (BTW, what is the proper term for the red part?)

Wow, are we nearing the end of the tunnel? I can't believe it! Shocked

So there are only two outstanding concerns left:

1) The two width joists (orange)--are they ok? I don't know how else to wrap the ceiling gypsum boards around that annoying existing ceiling support beam.

2) Confirmation that the detail in red is what you meant.

EVERYONE: You guys see how Rod helped me going from tearing my hair out and going insane to actually getting somewhere? This is one classy fella! Go buy his book! Hire him to design your studio from the ground up! If I could afford him I would've--it would have saved me from all this insanity. I have no idea how many braincells I killed trying to learn this on my own. I wasted months doing it the hard way. Don't be like me--hire Rod from day one and you can just kick back and relax.
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PostPosted: Fri Sep 05, 2008 1:05 am Reply with quoteBack to top

Lunatique wrote:
EVERYONE: You guys see how Rod helped me going from tearing my hair out and going insane to actually getting somewhere? This is one classy fella! Go buy his book! Hire him to design your studio from the ground up! If I could afford him I would've--it would have saved me from all this insanity. I have no idea how many braincells I killed trying to learn this on my own. I wasted months doing it the hard way. Don't be like me--hire Rod from day one and you can just kick back and relax.


Uh huh....

Try to tell you guys this over and over....

(myself included!)

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PostPosted: Sat Sep 06, 2008 9:42 am Reply with quoteBack to top

"The red--that is the detail you're talking about. That is how the walls parallel to the length ceiling joists should look. (BTW, what is the proper term for the red part?) "
/qoute

Deadwood.

It is typical framing procedure for anything framed of wood.
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PostPosted: Sat Sep 06, 2008 4:35 pm Reply with quoteBack to top

Up north here it's referred to as a ceiling backer....

What you are doing around the beam is fine - in fact it what I drew in the detail I sent you.

The important thing it to make sure that neither the ceiling joist nor the beam wrap ever touch the existing structure.

The guy who is annoyed at you is just showing his ignorance when it comes to isolation acoustics - believe me - there are some fine acousticians in China - and they most certainly would not consider the points I am making stupid because they don't do things like that in China.

Let him know that if he isn't talented enough to figure it out there is a bunch of people from all around the world who can who can get the job done for you- and then all he'll have to do is use the right colors if he happens to be the one putting it together.

I assume he isn't color blind.

Rod

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PostPosted: Sat Sep 06, 2008 10:31 pm Reply with quoteBack to top

I would say just go bigger then what you need. But I have respect for doing things the scientific way, so by all means pick the proper hanger Very Happy
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PostPosted: Sat Sep 06, 2008 11:25 pm Reply with quoteBack to top

Rod Gervais wrote:

The important thing it to make sure that neither the ceiling joist nor the beam wrap ever touch the existing structure.


Yes sir!

Quote:

The guy who is annoyed at you is just showing his ignorance when it comes to isolation acoustics - believe me - there are some fine acousticians in China - and they most certainly would not consider the points I am making stupid because they don't do things like that in China.

Let him know that if he isn't talented enough to figure it out there is a bunch of people from all around the world who can who can get the job done for you- and then all he'll have to do is use the right colors if he happens to be the one putting it together.

I assume he isn't color blind.


The guy who's overseeing the construction is just a typical construction guy who knows next to nothing about acoustics. He's been talking to a structural engineering professor at some university about my studio, and it was the professor that said those things. But the professor probably knows nothing about acoustics either, so... I talked to a few other people who actually design studios or have built them, and they don't seem to have any clue either--they just say to distribute the weight equally (take the weight of an entire wall or ceiling and divide by the isolation product's allowed optimal weight to figure out how many you need, and then just place them in equal spacing) and call it the day. It's frustrating since even I, someone who flunked math twice in school, can see that a door frame with hinges on one side will alter the balance of a wall so you can't just place isolation products at equal spacing.

Is the calculation hard to do? Could a non-expert be taught how to do it? Is my only option to spend money I don't have to hire an expert to do it? You explained it once in a previous post in this thread--I assume there are other details besides those you mentioned? This is what you posted:

Quote:
You have to be carefully when sizing the hangers to calculate the exact load - any hanger in the middle will be carrying exactly 1/2 the weight of the span - while the ends will only carry 25% in the length of the wall - drywall ceilings at the wall ends parallel to the studs will generally impart no loads to the wall (due to the cantilevel effect - a hanger each side of your concrete beam I see below the existing ceiling will carry 1/2 the weight of the box plus 25% of the ceiling (assuming a center support is used for the ceiling in that bay).

In between the concrete beams - if you only have the 2 end hangers......... then the hangers carry 1/2 the ceiling load and 1/2 of the box loads at each end.

Also be careful if the room is not symmetrical to the beams - in that case you will need to calculate the individual ceiling joist loads to determine what they are carrying - and will have to size each isolator to fit that particular load.

Don't forger to include the weight of the framing itself in the calculations.

What this ends up meaning is that you will probably have to use a lot of different capacity hangers - and must make certain that they end up in the right locations.

As far as your walls go - if you use a continuous pad like you show - the chances are it will not load up enough to act as an isolator.

It really needs to be pucks sized for the load of individual studs.

Again this gets tricky.

For example - if you have a door opening and one of my super doors installed for isolation - then the hinge side of the door would carry the load of the entire dfoor - plus 1/2 the load of any ceiling load attributed to the ceiling - plus 1/2 of the wall load to being carried by the door jamb and the nearest stud - while the opposite side of the door will only be carrying the other half of the ceiling load plus 1/2 the wall load from from it and the nearest stud on that side of the door.

Perhaps 50 to 100 pounds on one side - and maybe 450 to 400 pounds on the other.

2 different loads - and thus the pucks will be totally different in design requirements and capacity. (Size as well as hardness)

This will happen throughout the walls - with different load requirements on bearing versus non bearing wall - and even on bearing walls between the wall middles and the ends.

Again - if this gets screwed up - the pucks will act as transmitters instead of isolators.

Too much or too little compression will create that.


What you described about the ceiling joists--does it still work that way with the current ceiling plan that I have?

Need a couple of minor confirmations:

1) You mentioned that I really don't need those width ceiling joists (except for where I need to wrap around the existing support beams). Does that mean I can get rid of segments (pink width ceiling joists) 1 and 4 from the previous drawing, and just connect the remaining segments into two like in this updated drawing:
Image

2) So I don't need the extra wall braces? (The orange ones)
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PostPosted: Sun Sep 07, 2008 6:37 pm Reply with quoteBack to top

camsr wrote:
I would say just go bigger then what you need. But I have respect for doing things the scientific way, so by all means pick the proper hanger Very Happy


And you would be wrong on the first comment.

When you use isolators it is critical that they be sized properly - or else - instead of being isolators they become transmitters.

The hangers have a spread for the low to high end of their loading capacity - and you need to fit within that range.

If it was as simple as oversizing them there would be no real need to even bother calculating your loads - in fact the manufacturer would not have to bother making hangfers with different capacities - they would just make the one capable of the heaviest load and be done with it.

Perhaps you need to rethink your way of looking at things. The approach you mention actually fails as much as it succeeds. And the failures can cause real big problems.



Rod

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PostPosted: Sun Sep 07, 2008 7:38 pm Reply with quoteBack to top

OK - let's make this as easy as we can try -

for the ceiling you will have the wall at one end - and an iso hanger at the other end - the short ceiling is just that with nothing else.

SO in this case - 1/2 of the ceiling weight bears on the wall - and the other half bears on the hanger.

An example of the math here is easy -

Picture a 12' long ceiling section - with joists 2' on center and 2 layers of 5/8" drywall sitting on a wall at one end and one hanger at the other.

That means the hangers would be carrying 1/2 the ceiling (so 6' in length) - with a load 2' wide (1/2 of the joist bay on each side of the joist) for a total of 12 s.f. of ceiling load - plus the weight of the joist itself (this is part of the dead load).

With 2x6 doug fir framing the joist would weight about 1.89 pounds per linear foot - (D.F. weight is about 33 pcf.) so 11.34 pounds for the joist and about 2.5 psf for one layer of gyp - thus 5 psf x 12 sf - 60 pounds plus the 11.34 = 71.34 pounds per hanger.

The proper hanger in this case would be the Mason Industries W30 spring hanger with a body length of 4 1/2 inches (capacity is 12 to 95 pounds per hanger). As an option you could use a neoprene hanger in the WHR family (which should save you a few dollars) - in this case a WHR 45 (with a capacity of 55 to 95 pounds) would be acceptable. This hanger has a red mark.

OK - now lets look at a double hanger condition.

take a 24' ceiling with double layers of 5/8" drywall, 2x6 joist 2' on center - with a hanger at one end and another in the middle.

Just to give you a clear picture it works like this - if you have a weight bearing on 2 walls (that is not loaded from above) the each of the walls carries exactly 1/2 of the load.

If you then place a wall in the center - the center tall will carry 1/2 of the load either side of it - with the outside walls then carrying 1/2 of the new span - or a total of 1/4 of the entire span.

So with a hanger in the center - the middle hanger carries 1/2 of the load either side for a total of 12' of load per hanger - the outside wall gets 6' anf the outside hanger get's 6'.

All of the factors are the same here - so the outside hanger would be carrying the same 71.34 pounds per hanger - as would the opposite wall - and the center hanger would be carrying double that for a total load of 142.68 pounds of load per hanger.

As you can see the original hanger would be overloaded in the middle (but still ok for the outside) so we step uo to the W30 with a 4 3/8" body length which is capable of a load from 138 to 336 pounds. Agaion - with a neoprene hanger the size would be the WHR 60 ( 95 to 155 loading capacity) which has a white mark.

Now the walls -

Assume 8' high walls - 2x6 frame at 2' on center - with double 5/8" drywall -

the total weight per wall bay would be stud lengths of 8' plus a double top and single bottom plate - for a total length of 14' of framing - plus 16 s.f. of drywall for totals of
26.46 pounds of studs., plus 90 poinds of drywall plus the 71.34 pounds of ceiling load calculated above.

that's a total of 185.8 pounds per studd point load. The Mason Industries ND Mount for walls has ratings in this range for the Type "B" mounts of 110 miinimum load to 235 pound max load using the Color mark.

So a ND-B-Red would be a perfect match.

OK - a little bit about junctions at walls parallel to the joist.

If you have a joist sitting 2' away from a parallel wall - then the joist gets 1/2 the load either side - which means that the wall would only get 12" of ceiling load......... and that load would be broken down along the length of the wall - and not point loaded at one end.

So in this case - the wall load would still be 116.46 pounds per stud bay of 2' - but the ceiling would only add 2' square feet of drywall weight to that plus 2' of the weight of a 2x6 ceiling backer(3.78 pounds). For a total of 130.24 pounds per stud bay. You can still use a red mark isolator.

OK - just a note on the different hangers.

The first hanger I used is what I typically specify - it uses threaded rod to attach to the ceiling and to the joist - and is the detail you see in the drawings I sent you.

The advantage to this hanger is the accuracy and ease of hanging - but it costs more.

The advantage to the 2nd hanger (the WHR) is the lessor cost - but it hange from the ceiling on wire - and has to hang the joist with wire - which is a rsal pain to do accurately when framing.

For you I wold recommend the spring hanger and ease of installation - but I did have to make you aware of the options.

By now you should get the idea - it's not that deep.

As far as the question on the wall braces - actually you should keep the orange - and actually now that i am more focused on your room design - you should add one to the wall on the left - you really need one either side of that pesky concrete beam that will break your wall on either side.



I hope this helped some.

Rod

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Rod Gervais
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