# Framing "floating joist"



## patchesj (Jun 17, 2009)

Getting ready to finally start construction. I'm a bit confused on how one would attach floating joists to the isolated wall. I've always thought you should "block" the joists if they are larger than 2x6, and I don't see how that is possible with floating joists. Would you just nail up from "inside" the isolated wall and skip the blocking? Looks like there is no way to toe nail from the ends of the floating joists either. Decent diagrams of the concept here.. 

http://www.soundproofingcompany.com/library/articles/room_within_a_room/

Thanks


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## Ted White (May 4, 2009)

The floating joists can rest atop the inner theater walls or they can can be installed to the face with a ledger board or joist hangers.


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## patchesj (Jun 17, 2009)

The joists still need to be physically attached to the wall, right?

BTW- Ted, just submitted a quote request for some green glue on your site...


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## Ted White (May 4, 2009)

Yes, attached to the inner wall of a double wall system. So the inner wall is decoupled and so are the joists. All nicely decoupled


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## patchesj (Jun 17, 2009)

I guess that is the root of my question... Assuming the floating joists are only exposed by 1" below the floor joists, and then butt up (within 1" of..) the header for the floor joists (as ilustrated in the 2nd floating joist diagram on the linked page). The only way I can see to nail the isolated wall to the floating joist is to shoot a nail up from under the isolated wall top plate and into the bottom edge of the floating joist. Does that make sense?


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## Ted White (May 4, 2009)

Sure makes sense. And still perfectly isolating. I intorduced this method back in '99 and I used a screw through the top plate(s) into the floating joist. I also used upside down joist hangers. www.TedWhite.Homestead.com is an old, old non-updated website describing my build 11 years ago. See the terrible pics of what I'm describing.


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## bpape (Sep 14, 2006)

Dc-04 clips will tie the walls securely to the ceiling while still decoupling. Lay the joists on top of the walls for great iso with minimal headroom loss.

Bryan


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## patchesj (Jun 17, 2009)

Ted, the links for http://tedwhite.homestead.com/files/floating_ceiling_1.htm and http://tedwhite.homestead.com/files/floating_ceiling_2.htm seem to be broken. And it looks like you spaced your floating joists up about 1/2 inch on top of the interior walls, why?

Thanks!


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## Ted White (May 4, 2009)

I only wanted less than a 1" drop on new floating joists. This meant I had to adjust the height (up) of these joists as they rest on the top plate


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## patchesj (Jun 17, 2009)

Could you have just built the walls 1" taller or where there clearance issues elsewhere? 

Thanks


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## bpape (Sep 14, 2006)

If you build them taller, they're then reconnected to the structure of the house and the new joists end up at the same level as the old ones so there's really no point as there's no isolation then.

Bryan


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## patchesj (Jun 17, 2009)

I was thinking build the walls 1" shorter than the structure above and resting the floating joists directly on the top plate. It looks like ted built the walls 2" shorter and then shimmed the joists 1" above that. 6 of one, .5 dozen the other?


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## Ted White (May 4, 2009)

I perhaps could have but that was 11 years ago...


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