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post #31 of 303 Old 03-18-2014, 10:28 AM
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blank canvous let the fun begin biggrin.gif
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post #32 of 303 Old 03-19-2014, 05:52 AM
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Subscribed. Excellent documentation. I kinda suck at that. What speakers are you planning on going with in your new space? I'm an M&K guy, too, but was looking at some of the DIY Sound Group stuff as a possibility down the road.
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post #33 of 303 Old 03-19-2014, 07:24 AM - Thread Starter
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I haven't yet decided on the speakers, other than I'm going to make them myself. Subs, too. It's most likely that I'll decide on which ones just before I actually start building them.
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post #34 of 303 Old 03-22-2014, 08:25 PM - Thread Starter
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Ah, nothing like crippling indecision. One of the reasons I put off quite a bit of decisions until the last possible moment is because I know myself -- I know that I will agonize over a steadily expanding tree of choices and never be able to make any decision at all. So I just take it one step at a time, to allow myself some kind of progress.

Well, I'm at one of those stages where I need to make a lasting decision, but I keep wildly flip-flopping between the two non-ideal possibilities. I do have a few more bits I can do... but since this involves the walls, I need to decide very soon.

Okay, so three of my four walls are exterior walls and thus need to be insulated for thermal efficiency in addition to for soundproofing. Very technically speaking, I can get away with the normal R-13 used in the soundproofing component since I'm in AZ and that's all that is needed for walls. I want more, though. So I bought some sheets of 1" Polyiso rigid foam which is somewhere around R-6. That'll give me R-19, which is just about perfect.

My original plan was to glue the foam to the slump block exterior walls. My full wall setup would then look like so:

7.5" Block + 1" PolyIso Foam + 1" air + 2x4 frame w/ R-13 fiberglass + OSB + GG + DW

Looks good, right? Well, I have an open attic above my theater and that causes all sorts of problems. Because it's open, that means that the 1" of air space in that wall setup is now essentially attic space. Attic space gets up to 160 degrees in the summer. If I had a pocket of 160 degree air between my foam and my fiberglass, then doesn't that completely invalidate the foam? Now, it wouldn't be quite like that since I'm going to have to seal off that 1" air gap no matter what, or else my blown insulation will be falling into that crack. I was planning on putting a piece of drywall across that gap, which will stop any insulation from falling and also act as a fire stop. But even sealed, that drywall isn't going to provide much thermal resistance. It's prevent conductive heat transfer, but since the insulation on top of it will be minimal (it's where the roof meets up with the wall), there will still be significant amounts of heat radiating down into that space.

So I'm now flip-flopping on another plan. What if I attached the foam directly to the 2x4 wall? Then it would look like so:

7.5 Block + 1" air + 1" PolyIso Foam + 2x4.... yadda yadda

In this case, the foam would be sealed to the 2x4 wall and so I get 100% of the thermal efficiency. The air pocket would still be notably hot, but who cares because my R-19 is there to slow that heat transfer down (instead of just R-13 from before).

Even better? Well, it has the notable problem of how to transition from the exterior walls to the interior wall. There would be notable gap of any insulation right at that point where the exterior wall continues past the insulated inside wall. That happens on both sides of the room. This could easily make my non-exterior wall the problem area for thermal efficiency.

Maybe I could work around that by stuffing some fiberglass in the air space right at that point where the exterior walls meet the interior walls. That should keep the super-heated air from making the corner into the fourth (cooler, interior) air pocket.

But if I'm going to be stuffing insulation into gaps, then why don't I go with my first plan and stuff insulation right underneath the drywall topper. It would be wedged between the foam and the 2x4 wall, but only the top few inches. That could give me my insulation on the top and allow that air space to never get super-heated in the first place.

Flip-flop. Flip-flop.

Neither solution is obviously superior to the other from my perspective. I need to choose one of them sometime in the next week, though.
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post #35 of 303 Old 03-22-2014, 09:29 PM
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Wow. My head hurts and it's not because of the booze this time.

Have you thought about paying a few hundred bucks and having a consultant advise you? Maybe a mechanical engineer that designs HVAC systems or maybe a really knowledgeable HVAC technician? Might be worth a few hundred for someone to come out and take a look.
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post #36 of 303 Old 03-23-2014, 11:14 PM - Thread Starter
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Minor Update - Mar 23, 2014

I didn't get a lot of time to work on the theater this week, due to it being so nice outside. What's that got to do with it? Well, the trees need pruning, the weeds need addressing, the grass needs cutting, the pool needs maintenance, &c. Gotta do it before it gets hot. Gotta get the theater sealed in before it gets too hot, too... but that's far less likely.

Anyway, I did spend more than a little time going back and forth on where to put the rigid foam, as evidenced in a previous post. For actual work, I removed the very last tiny bits of the old stuff to make it 100% deconstructed (i.e., I'm not expecting any more old debris from the room anymore).

I also attached some particle board to the hall wall above the false lowered ceiling of the hall. That is, I had already attached particle board to the part of the hall wall that's below the ceiling (and taped and mudded it), but the part that was above the wall in the attic was still open. Enclosing it doesn't matter a whole lot from a soundproofing perspective since it's sort of just hanging out there... but it will keep the blown in cellulose from tumbling into my double wall air space. I didn't bother doing a careful job of sealing it -- just a single layer of tape and mud where there were a few egregious cracks. Again, that's just to keep the upcoming cellulose at bay. I did need to do some careful cutting on one of the pieces, to fit it into the existing space, jigsaw puzzle piece style:

Sheathed above the hall ceilingJigsaw puzzle piece

And I reaped the very first benefit of what I sowed earlier. One of the main purposes of my deconstruction vs demolition was to be able to re-use as much of the components as possible. Now was the first time that I could re-use something -- the insulation. I filled in the hall way bays with a dual layer of insulation. It had to be a dual layer because the reclaimed insulation was all behind a 1-3/4" wall (just strapping) and so it's half the thickness of normal R-13 fiberglass. Not all the pieces were full length, either, so there's a lot of patchwork. It wouldn't be ideal as a primary thermal barrier, but it should do the job nicely as an absorption layer and as an air pocket "multiplier" in my dual wall setup:

Insulated hall wall

Note the polyiso foam hanging out on the side, there. I think I may have come up with a decision on that front. I'm going to go with my original plan. The way I see it, since I have two plans that seem equally good and equally dubious and I can't decide which is better on their merits, then I might as well go with the one that I already made up a Sketchup model for. Oh, is that a silly reason? Yeah... but hey, it beats flipping a coin. I'm going to start gluing the panels to the wall next week. They will each be 1-1/2" inch off the floor to make them even with the top plate on the exterior walls, and then I'll fill in the gap on the bottom with Great Stuff expanding foam.
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post #37 of 303 Old 03-30-2014, 08:25 PM - Thread Starter
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Update - Mar 30, 2014

I attached the polyiso rigid foam on all exterior wall surfaces. It took longer than it would for most people, largely because I am more of a perfectionist, even for something like this. At first, I applied the glue (PL375) in globs to the back of the foam itself:

Glue on foam

It needed to be in rather large globs since the wall was so bumpy and this increased the chances that more of the glue will make contact with both surfaces. As is, quite a few of those globs still never touched, so I didn't do it like that the entire time. It went through a lot more glue than I originally thought, too. See, I originally bought the standard 10oz cans and I assumed I'd be able to glue up three 4x8 pieces per can. I eventually got a 28oz caulk gun and so I returned those and got only a couple of 28oz cans of the glue. It turns out that I drastically underestimated how much glue I'd go through, as the 28oz can (three times larger than my original 10oz cans) only handled 4 pieces. That meant that I would have gone through an entire can for each piece of foam, originally!

Handily, though, I was able to use normal construction adhesive and not the "foam board" crap. That's the blue stuff. I used that some time back and it was absolutely useless. It's needed for EPS or XPS foam, though, as normal construction adhesive will "melt" the foam. Polyiso has an aluminum foil backing which prevents that and so I could use a variant that actually worked.

I pressed each piece against the wall and then put weight on the top of the foam using a 2x6 and the bottom using a piece of slump block:

First piece of foam up

Yeah, that's a laser level. My wife was incredulous that I'd use a laser level on a piece that will never be seen after the walls go up. Who cares if it's perfectly plumb, she asks? Well... I don't have an answer for that other than I care and the reason it needs to be plumb is "just because it does."

Note, too, the shims under the bottom. My original plan was to put the foam on a 2x4, so it was 1-1/2" up and level with the top plate. It turns out that the walls aren't exactly the same height all the way around and so the foam sheets wouldn't be flush with the top plate in all cases. I decided, instead, to consistently shim the foam up 1/4" on the bottom and to leave a gap of an inch or so on the top. I would then spray expanding foam on the bottom and the top to fill in the bottom and even off the top.

There was one outstanding area that I wasn't sure how I'd handle until I got to it and that's where the wires snaked down the wall for the exterior coach light, door bell, and outlet box:



I ended up just gluing a panel right over them. I figured that they were hidden behind a wall before and so they would be hidden behind a wall again. After the glue had cured, my wife brought up the point that maybe the difference is that now the wires are glued in place and before they were free in the stud bay. The latter case would be easier if we ever need to replace the wire. Maybe. On the other hand, the wire is cemented into the wall and so it wouldn't have been trivial to pull it up no matter what.

After the first day (and first can of glue), I decided to start applying the glue directly to the wall. That way, I'd know to hit the high spots and guarantee better coverage. Since it's not hit-or-miss, I also ended up using less glue:

Glue on wall

In this case, the laser line actually came in handy for letting me know where to apply the glue. You may or may not notice that my shims are slightly different. I switched to using a length of 1/4" plywood and then inserted normal shims as needed to get the pieces plumb. The 1/4" plywood lengths will later be used when doing the drywall/OSB layers.

At this point, getting all of the necessary 2x6s into position to keep pressure on the foam was becoming increasingly tricky. Each piece is 12' long, so moving them around all of the existing pieces was extremely tricky. It was a veritable forest of 2x6s:

Forest of 2x6s

After all of the foam was up, I started on the gaps using Great Stuff expanding foam. I had purposefully left a 1/2" or so gap between the foam in the corners because there was no way of getting those to be tight. I filled in those gaps with foam:

Foam in gaps

I don't know if you can see it in the picture but there are some areas there where the foam didn't expand very much and left gaps. Those gaps have been a constant problem for me as long as I've used Great Stuff (which is a decent bit). Sometimes it works like a charm and sometimes it barely expands at all. I have never been able to figure out what the difference is.

Well, a few minutes ago, I saw some videos by Dow that might have shed some light on this. They claim that Great Stuff requires at least 50% relative humidity in order to cure properly, or else it will shrink. This is Phoenix AZ we're talking about, and 50% humidity just ain't happening! So next time I'm going to spritz it with some water and see if that helps or not.

I also finished up a can by spraying underneath the panels to fill the 1" x 1/4" gap. That seemed to work fine. I actually have a "pro" gun for Great Stuff which is a lot more precise, but since I have a couple cans of the normal stuff, I figured I'd use them first. I do still need to do the next half of the room.

I likely won't apply the foam to the top of the panels until I build the walls... for reasons.

Oh, I also taped all of the seams with house wrap tape, to prevent air gaps:

House wrap

When all's said and done, it looks like so:

Final foam paneled room

I still have one full sheet of foam that I don't know what to do with, plus a bit of left over. We'll see.

Next week, I'm going to finish off applying the expanding foam where it could use it. I'll also look into replacing all of the newish white fiberglass with the old pink stuff, since the new stuff will likely fit better in my upcoming interior wall. While I'm at it, I'm going to attach some leftover pieces of drywall to one of the common walls, just to give them more mass (and why not, because it's all scrap drywall that would otherwise go in the trash). At some point SOON, I'm going to need to paint those windows. That needs to be done before it gets too hot.
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post #38 of 303 Old 04-01-2014, 08:30 AM
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Looking good Granroth... Let me know when your ready.. I got a drywall lift that ill pass along..

My Basement HT Construction ~ Faster than the speed of Dark

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post #39 of 303 Old 04-13-2014, 11:43 PM - Thread Starter
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Very Minor Update - Apr 13, 2014

I haven't made a huge amount of progress on the theater, mostly for two reasons. First was a full week mostly gone doing taxes -- hours of tracking down and scanning receipts and then finding out I did the taxes wrong, along with doing last year's taxes wrong, and having to file a 1040X "amended tax return" and all the fun stuff like that. I finally got past that... and wasted almost a full week being sick and barely able to stand on my own two feet for more than a tiny bit in the heat of the theater (we're officially at over 100 in the theater space every afternoon now). So yeah... not a lot.

My wife and I did get to sneak in (finally) painting the two windows. They are both fiberglass, but have a faux wood finish called "EverWood" that is stainable. We got that (and even paid extra for it) because we had some grandiose plan of staining it cherry or walnut or something like that. It was only after we had them installed and looked at what those would look like in wood colors that we realized that it wouldn't match our house at all... and so we have resorted to painting them with a black latex paint, completely wasting the expensively stainable aspect of them.

Anyway, they start out looking like so:

Bare windows

We taped up some of the important bits and then put on two coats of paint, followed by one coat of polycrylic. They are all water based layers so we only need to wait a couple hours between coats... especially in the extreme drying times given our dry and hot weather. Notably, we did not tape the glass at all this time and made a concerted effort to purposefully overlap the paint and clear coat on them:

Purposefully messy window

The intent of this is to form a film of paint and clear and then just smoothly scrape it all off in one go with a razor blade. And.... it worked fantastically! We got a clean line that no amount of careful taping could have accomplished and it was very quick. Unfortunately, I have no good pictures of that (yet). But take my word that the line is just about perfect. These are the last two of eight windows and we're kicking ourselves for not doing this for the other six.

The other thing I accomplished, then, was beefing up the short common wall a little bit. There is one span off wall that is roughly two feet wide that is shared with our living room and has a direct line of sight to the bedroom hallway. If there was ever a weak spot in the theater, it would be right there. I'm going to do three layers on the inside in that spot, but I figured that since I had some spare bits, I might as well add some mass to the existing wall.

I had actually saved some of the drywall from the closet I tore down and so I cut some pieces out of that and glued it between the studs:

Added drywall

It's only 1/2" drywall and there's not a great fit and I didn't do any caulking or Green Glue... but that's not really my goal, here. My goal is to just add some "free" mass from bits that I had left over.

For a second layer, I got out some leftover 3/4" particle board (like what I used to build the outside hall wall) and glued that up. I was full blown sick at this point and this required ripping to width on my table saw... which probably wasn't a good idea in my state. But I did it anyway:

Added particle board

In the end, that wall ended up being 1-3/4" thick (two layers of 1/2" drywall plus one layer of 3/4" particle board) giving me roughly 5psf -- which is better than nothing and I got to reuse some scrap without having to toss it.

Next week, hopefully I'm well enough to actually start framing the inner walls!
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post #40 of 303 Old 04-13-2014, 11:52 PM - Thread Starter
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Quote:
Originally Posted by KNKKNK View Post

Looking good Granroth... Let me know when your ready.. I got a drywall lift that ill pass along..

Oh, sweet! I'm probably a few weeks out for that... maybe a couple of months. I've already resigned myself to the fact that I'm going to be working without A/C in that room when it's 115-120. C'est la vie.

It's funny, though -- I saw in your profile that you list AZ but when I read the first couple pages of your build thread, it was all about your theater in Indiana and so I just assumed that the AZ tag was from before (or something?) After your drywall lift offer, I finished reading through your build thread to clarify my confusion and sure enough -- you are likely just south and east of me, since last summer. Nice!
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post #41 of 303 Old 04-14-2014, 07:50 AM
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Wow - quite the build!
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Check out a video of my theater here
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post #42 of 303 Old 04-14-2014, 11:09 PM - Thread Starter
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A Tiny Spark

One thing about soundproofing is that you can't really know how well it will work until you are completely done. I can make some educated guesses by comparing the walls I make with existed tested walls... but even then, it won't be the same. Every single detail matters so much that any deviation from the tested wall will end in a different result.

I did have a infinitesimally tiny taste of what might be, this evening. My above post was about how I added some 1-1/4" of extra mass to the short common wall with our primary living quarters. I was curious how much of an impact even that little bit could make. The reason that occurred to me was because I was standing around that area and gradually realized that while I could hear what was happening in the living room pretty clearly (my son watching TV and my wife on the phone), I wasn't hearing it from the direction of the wall. Instead, the sounds appeared to come from the open doorway (I don't have a door to the theater, yet). That meant that the sound would rather go down some 25 feet of hallway and make three right turns rather than take the 5 foot straight shot through the wall. I decided to test this a little bit.

I got out my shop-vac and placed it one foot from the wall and turned it on. From one foot away, I measured just under 80dB and a FFT graph showed a surprisingly flat frequency set. I then walked over to the living room and stood opposite to the wall -- so roughly two or three feet from the running shop-vac. From that vantage point, I could clearly hear the shop-vac (roughly 55dB) but it was entirely coming from the hallway. I couldn't hear anything coming from the wall... even though we're talking 80dB less than three feet away! I could hear it clearly if I pressed my ear to the wall, but it was by no means loud.

The fact that such a tiny bit of soundproofing (and such an ad-hoc method, at that) would give such an outsized result definitely picked up my mood.

You see, I'm overall getting a bit pessimistic about what my end result will be. I essentially have three goal levels that I could meet. The highest level is where I would be thrilled by the result. The second level is where I'd be happy with it. The third level is where I'd be okay with it.

Result Oriented

A thrilling result would fit this pattern -- I have a movie (or trailer or whatever) playing in the theater at maybe 85 or 90dB (maybe a little less) when people come over. As they approach the theater door, they cannot hear any indication that there is something playing. As I open the door, though, the sound just pours out and you realize that that complete silence was masking something that was pretty darn loud.

My happy result would be if you could feel the bass outside of the theater and maybe some moderate rumbling, but that you couldn't hear that it was playing at all on the other end of the house (the bedrooms).

My okay result would be if you could clearly hear that something was playing, but it was indistinct enough that you could treat it as white noise and still get to sleep and not be bothered by it.

At this stage, I'm fairly certain that I won't hit my thrilling result and am increasingly worried that I might not even hit my happy result. I darn well better hit at least my okay result!

Flanking

The problem is the flanking. I'm designing this to be a room-in-a-room with floating joists, which should give me the best reasonable decoupling. But here's the problem -- I'm not actually doing true floating joists and it's not a true room-in-a-room! The problem is the fact that I'm in a single story house and the space above the theater is my attic.

See, when most people talk about floating joists, they are referring to the fact that they are threading the joists in-between the floor joists from the floor above them. This creates a Mass-Air-Mass setup, where the theater ceiling is the first mass and the floor above is the second mass.

I don't have any floor above me. There is just Mass-Air... and that's it. There's no other mass. That means that the sound could go up through the ceiling into the attic and then scoot across the wide open space to anywhere in the house and dart down into another room, completely bypassing my beefed up double walls.

I asked about this on some hard-core soundproofing/acoustics forums, but the only real solution I got was one that I can't implement due to space constraints (building a "floor" above my theater and sealing off the theater from above).

Based on this, I'm pretty sure enough sound is going to escape through the ceiling to invalidate my thrilling result. The big question is if enough will be enough to block the sound from getting into the bedrooms.

Maybe Still Happy

The only reason I think I might still get my happy result is thinking about the attic as a much bigger "wall". For sound to get from the theater into another room, it would need to go through 5/8 DW+OSB (my theater ceiling), then R-50 of blown cellulose, then 5 to 50 feet of attic space, then another R-50 of cellulose on the way down, and then another 1/2" DW. That's arguably a Mass-Air-Mass setup from that perspective, albeit with a lot of Air and only a little bit of Mass on one side.

But here's the deal -- I won't know until it's actually done and it's already at a point where it's too late for me to do anything about it. Hrmph.

C'est la vie, I guess.
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post #43 of 303 Old 04-17-2014, 11:18 PM - Thread Starter
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I'm wondering what the best way is to handle my uneven floors. Uneven floors aren't unexpected, of course -- any house built on a slab is bound to have a floor that is visually level, but actually varies by a bit. In my case, my theater floor isn't level in any particular direction. Think of it as softly undulating waves. For instance, one one wall, I measured both ends plus the middle and found 0", + 3/8", -1/4" -- so the height difference from the middle to one end is 5/8". Indeed, the maximum difference in height from the high to the low point of the floor is 1". Those two points are a good 15' apart, though.

In general, the floor "looks" flat and the two bedrooms that were there before "appeared" to have flat ceilings. They weren't, though.

I could handle this in at least three ways:

1. Create all of the walls on the floor to be square and true and then shim under the bottom plate to make sure that the top plate is level. I couldn't reasonably do this around the entire room since that would mean "shimming" one of the walls up a full inch (the difference between the high and low point) and that's not even shimming anymore. So I'd likely just level out each wall section. The ceiling wouldn't be perfectly level, but it would undulate less.
2. Create all of the walls on the floor to be square and true and then just let them naturally curve on the floor to roughly match the existing undulations. This would create a ceiling that was essentially parallel with the floor (give or take a little). This is the easiest (by far) but would result in the ceiling undulating the most.
3. Attach the bottom plates to the floor and let them naturally curve. Then strike a level line across the entire theater at the height of the bottom of the top plate and custom cut each stud to fit. This would result in a ceiling that is dead level across the entire theater. It would also be the most labor intensive method.

To some people, the answer might be obvious. If so, I wonder which one it is, since it's not obvious to me. There are pros and cons to each approach.

My "good enough" side says that option 2 is the way to go since not only would the ceiling appear to be flat, but it would be hidden anyway since I'm putting a soffit all the way around. And I could scribe the soffit so that it is perfectly level, if I wanted to.

My "now is the time to do it right" side says that even though custom cutting each stud is more work, I only need to do it once and I'll have as close to a perfect ceiling as I could hope for. Would the 1" wall height difference bet noticeable (by me -- nobody else would be paying attention)?

OR AM I OVERTHINKING THIS?

Here are some raw numbers, to see if I'm insane.

I started out in the right corner of the screen wall and arbitrarily set that to my zero. I then measured roughly every 6 feet along enough wall, relative to that zero. All measurement listings are from front to back (side walls) or from right to left (front/back walls).

The right wall is: 0", -1/8", -1/8", -1/8"
The back wall is: -1/8", -1/8", -1/4"
The left wall is: 0", 0", -1/2", -1/4"
The front wall is: 0", +3/8", 0"

Hmm... maybe if I took a grinder to the high spot on the front wall and filled in the lower spot on the left wall...
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post #44 of 303 Old 04-18-2014, 04:34 AM
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Walls don't define the ceiling if you shim the joists, build them all an inch short and attach with IB3 clips. You are over thinking this. Shim your floating Ceiling joist so that they are all level. Use a laser and a stick. Position a laser at 7 ft or so and then use a stick to measure to the bottom of each joist. Draw a line at the tallest. Now make them all that height.
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post #45 of 303 Old 04-18-2014, 04:28 PM - Thread Starter
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Originally Posted by BIGmouthinDC View Post

Walls don't define the ceiling if you shim the joists, build them all an inch short and attach with IB3 clips. You are over thinking this. Shim your floating Ceiling joist so that they are all level. Use a laser and a stick. Position a laser at 7 ft or so and then use a stick to measure to the bottom of each joist. Draw a line at the tallest. Now make them all that height.

Thanks, BIG, that's a different way of looking at this and is much better than any of my solutions. Sweet.

I am curious about the reference to "build them all an inch short and attach with IB3 clips" as I'm not sure what that means in this context?
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post #46 of 303 Old 04-19-2014, 07:53 PM - Thread Starter
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Building a Wall (Section)

Here's how I'm building the interior walls of my theater. There's going to be a bit more detail in this post than normal because why not?

I decided to build the walls on the floor and in sections, since that's the easiest way to do them as well as the most accurate (stud spacing, being square, etc). I'm building them in 10' sections mostly because I can't fit studs longer than 10' in my car's passthrough and I only rent a trailer if I need to by panels. The bottom plate is pressure treated since it's on a concrete slab, and all of the studs are 7' 9" -- nearly all left over from the earlier bedroom deconstruction. They ain't pretty, but they'll be inside the wall so who cares.

Here's my primary tools to start:

Tools

That's a 20oz framing hammer. It's utterly useless for "normal" nailing purposes but you cannot believe how much better it is for framing than a typical 16oz hammer. Night and day. 16d nails sink easily in just a few blows with this bad boy. I'm using hot tipped galvanized 16d nails for the bottom for two reasons. First, the bottom plate is PT and that will corrode a non-treated nail. Second the head of the nail will be resting on the concrete since I'm nailing through the plate to the studs (not toe-nailing) and that is also a corrosion concern. The Paslode cordless nailgun is mostly for my 8d needs. I'll primarily use that later. Honestly, I can't recommend a Paslode. They are finicky as hell and don't give you any feedback as to what the problem is when they stop working (which is frequently). Not at all worth it. I mostly use it for toe-nailing since it's a lot easier than using a hammer for that purpose.

Those two 2x4s are my stud spacers. Some people mark the centers of all studs on their bottom and top plates but that's not my style. I'd prefer to make 100% repeatable actions by using stops. Each of these spacers are for studs that are 24" on center. The bottom one is actually 21-3/4" to account for the starting full stud plus half of the next stud and the top one is 22-1/2" to account for the 1/2 a stud on both sides. In each case, the resulting studs are 24" O.C.

I started by building the corner stud. It just two 2x4s combined at a 90 degree angle with a few 8d nails. It looks like so:

Corner studs

The traditional way to handle a corner is to stack three studs next to each other. This gives you a nailing surface for the perpendicular wall as well as a screwing surface for the drywall. This wastes a stud and results in a non-insulated space, though. There's an increasingly popular framing technique known as "advanced framing" (sometimes "green framing") that is all about framing to reduce the number of studs and to increase the amount of insulatable space. Designing an energy efficient wall often has the exact same goals as designing a soundproofing wall and the same resulting techniques. This is one of those cases. By using two studs in this configuration, I save a stud; have more space for fiberglass for both insulation and for sound attenuation; and have less stud space to conduct sound through the wall. Win-win all the way around.

The studs are all connected to the bottom plate with two 16d nails (except for the corner stud, which only has one since it's mostly connected to the end stud):

Nailing the studs

I use the spacers to keep the studs at exactly 24" O.C. To nail each one, I butt the new stud up to the spacer and then step on it with a decent amount of my weight. This gives me a solid base to start hammering. If I don't step on the stud, then the entire setup bounces around too much and it's far harder to hammer.

First stud spacerMain stud spacerHammering procedure

For the header, I switched to 16d coated sinkers since galvanized is overkill and coated sinkers are easier to work with.

Starting the header

My earlier photos showed me using the spacer on its back, but I actually normally use it on its side. My spacer's ends are square, so it gives me a quick way to verify that the studs are square to the wall in that direction. In this case, the left stud was somewhat warped and so I just clamped it into place to be square when I nailed it in.

When it's done on the floor, it looks like this:

Finished wall frame on floor

Note the missing stud on the left end. That's where this section will join up with a new section. I'll butt them together and then toe-nail a stud that straddles the line, with a pair of nails cross hammered into the other wall section.

I previously had penciled in a straight line roughly 4-1/2" outside the exterior wall (slightly more in some places) and so I just placed the new wall section on it. It's attached to the concrete using powder-actuated nails:

Ramshot nail gunSunken nail

Powder-actuated nails is a fancy way of saying it's a .22 caliber gun that fires nails instead of bullets. There is literally a .22 caliber cartridge that you put in the gun and when it explodes, it propels the nail with enough force to actually bury itself in concrete. It's very easy to use, but I wasn't sure if it would work. I can't use the highest power cartridge with the gun model I have and I was worried that the 30 year cured slab might be too hard for it. That was the case in several parts of my previous addition. If it didn't work, then I was going to try some Tapcon screws and a hammer drill. If that didn't work, then I was going to go all-out with my hammer drill and use wedge anchors.

I may still put at least one wedge anchor on each wall, just to make sure that it doesn't move at all. I'm not entirely certain if the nails I just used will corrode over time or not. I didn't put any construction adhesive down in this section since I wasn't sure what method was going to work, but I will put a few globs down for each remaining section. I was tempted to put a line of caulk along the entire bottom, too... but honestly, that would be overkill, since I'm going to be fully sealing the bottom when I do the paneling.

Here's what the wall section looks like raised up:

Raised wall

The angled 2x4 is there to keep the wall upright for now. I'll eventually fine tune it to ensure that the wall is plumb before putting up any perpendicular walls. There is currently only one header layer but there will eventually be two. The second layer will be added after the entire room is walled in. That way, the upper header can span all of the butt joints and the entire wall will be far more rigid as a result.
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post #47 of 303 Old 04-21-2014, 02:59 PM
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Originally Posted by granroth View Post

A Tiny Spark

One thing about soundproofing is that you can't really know how well it will work until you are completely done. I can make some educated guesses by comparing the walls I make with existed tested walls... but even then, it won't be the same. Every single detail matters so much that any deviation from the tested wall will end in a different result.

I did have a infinitesimally tiny taste of what might be, this evening. My above post was about how I added some 1-1/4" of extra mass to the short common wall with our primary living quarters. I was curious how much of an impact even that little bit could make. The reason that occurred to me was because I was standing around that area and gradually realized that while I could hear what was happening in the living room pretty clearly (my son watching TV and my wife on the phone), I wasn't hearing it from the direction of the wall. Instead, the sounds appeared to come from the open doorway (I don't have a door to the theater, yet). That meant that the sound would rather go down some 25 feet of hallway and make three right turns rather than take the 5 foot straight shot through the wall. I decided to test this a little bit.

I got out my shop-vac and placed it one foot from the wall and turned it on. From one foot away, I measured just under 80dB and a FFT graph showed a surprisingly flat frequency set. I then walked over to the living room and stood opposite to the wall -- so roughly two or three feet from the running shop-vac. From that vantage point, I could clearly hear the shop-vac (roughly 55dB) but it was entirely coming from the hallway. I couldn't hear anything coming from the wall... even though we're talking 80dB less than three feet away! I could hear it clearly if I pressed my ear to the wall, but it was by no means loud.

The fact that such a tiny bit of soundproofing (and such an ad-hoc method, at that) would give such an outsized result definitely picked up my mood.

You see, I'm overall getting a bit pessimistic about what my end result will be. I essentially have three goal levels that I could meet. The highest level is where I would be thrilled by the result. The second level is where I'd be happy with it. The third level is where I'd be okay with it.

Result Oriented

A thrilling result would fit this pattern -- I have a movie (or trailer or whatever) playing in the theater at maybe 85 or 90dB (maybe a little less) when people come over. As they approach the theater door, they cannot hear any indication that there is something playing. As I open the door, though, the sound just pours out and you realize that that complete silence was masking something that was pretty darn loud.

My happy result would be if you could feel the bass outside of the theater and maybe some moderate rumbling, but that you couldn't hear that it was playing at all on the other end of the house (the bedrooms).

My okay result would be if you could clearly hear that something was playing, but it was indistinct enough that you could treat it as white noise and still get to sleep and not be bothered by it.

At this stage, I'm fairly certain that I won't hit my thrilling result and am increasingly worried that I might not even hit my happy result. I darn well better hit at least my okay result!

Flanking

The problem is the flanking. I'm designing this to be a room-in-a-room with floating joists, which should give me the best reasonable decoupling. But here's the problem -- I'm not actually doing true floating joists and it's not a true room-in-a-room! The problem is the fact that I'm in a single story house and the space above the theater is my attic.

See, when most people talk about floating joists, they are referring to the fact that they are threading the joists in-between the floor joists from the floor above them. This creates a Mass-Air-Mass setup, where the theater ceiling is the first mass and the floor above is the second mass.

I don't have any floor above me. There is just Mass-Air... and that's it. There's no other mass. That means that the sound could go up through the ceiling into the attic and then scoot across the wide open space to anywhere in the house and dart down into another room, completely bypassing my beefed up double walls.

I asked about this on some hard-core soundproofing/acoustics forums, but the only real solution I got was one that I can't implement due to space constraints (building a "floor" above my theater and sealing off the theater from above).

Based on this, I'm pretty sure enough sound is going to escape through the ceiling to invalidate my thrilling result. The big question is if enough will be enough to block the sound from getting into the bedrooms.

Maybe Still Happy

The only reason I think I might still get my happy result is thinking about the attic as a much bigger "wall". For sound to get from the theater into another room, it would need to go through 5/8 DW+OSB (my theater ceiling), then R-50 of blown cellulose, then 5 to 50 feet of attic space, then another R-50 of cellulose on the way down, and then another 1/2" DW. That's arguably a Mass-Air-Mass setup from that perspective, albeit with a lot of Air and only a little bit of Mass on one side.

But here's the deal -- I won't know until it's actually done and it's already at a point where it's too late for me to do anything about it. Hrmph.

C'est la vie, I guess.
I am on the second floor in a bonus area over the garage ( I hate to call it that as it was designed as a theater by me and my builders architect but for visual that is an easy way to describe it) so I do not have a floor above my ceiling or even drywall in the knee wall side of the attic space on both sides. I was thinking the same as you flanking noise. I used clips and channel in front, sides and ceiling, with double wall in the rear and R13 in the walls and R19 above the ceiling. No issues. If I were not satisfied with the results than I was thinking I would add 3/4" T&G above and drywall on the attic access areas. Another thought was to continue the billiard room wall to the roof and put R13 in that new wall. With Hobbit playing at reference during the mountain stone giants fighting (Which is Damn loud with 2ea 12" Sealed 500 W plate amp Subs and my Denon X-4000) you can just barely hear that something is going on on the other side of the door and feel some rumbles from the LF. I am not sure from a sound proofing perspective what the difference is between blown in cellulous and R19 roll but maybe you will want to do the R19 roll with the cellulous on top.

I used spray foam in the attic of my home build and am really pleased with it. In the summer in GA it barely gets above 80 degrees up there. (a different kind of hot from AZ with 100 degrees with 90% humidity) The entire attic is a conditioned space. If your air handler is in the attic I think you should give this some serious thought vise blown in cellulous since you are already putting so much into this build. That would also assist you with the dilemma you were discussing earlier. It would literally pay for itself in a few years in that heat.
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post #48 of 303 Old 04-23-2014, 07:11 PM - Thread Starter
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Originally Posted by cw5billwade View Post

I am on the second floor in a bonus area over the garage ( I hate to call it that as it was designed as a theater by me and my builders architect but for visual that is an easy way to describe it) so I do not have a floor above my ceiling or even drywall in the knee wall side of the attic space on both sides. I was thinking the same as you flanking noise. I used clips and channel in front, sides and ceiling, with double wall in the rear and R13 in the walls and R19 above the ceiling. No issues. If I were not satisfied with the results than I was thinking I would add 3/4" T&G above and drywall on the attic access areas. Another thought was to continue the billiard room wall to the roof and put R13 in that new wall. With Hobbit playing at reference during the mountain stone giants fighting (Which is Damn loud with 2ea 12" Sealed 500 W plate amp Subs and my Denon X-4000) you can just barely hear that something is going on on the other side of the door and feel some rumbles from the LF. I am not sure from a sound proofing perspective what the difference is between blown in cellulous and R19 roll but maybe you will want to do the R19 roll with the cellulous on top.

I'm very glad to hear that! I was originally thinking that your theater was detached from the rest of your house, but re-looking at your earlier pictures, I can see how the attic continues onto the pool room and beyond. My open space is quite a bit larger, but the concept is the same, so I'm hopeful that the results will be as well.

As far as fiberglass vs cellulose goes, I'm mostly approaching that from an energy efficiency perspective. Cellulose is cheaper, has mildly better R-value per inch, and is far less toxic. All in all, it's an ideal inexpensive attic insulation.

It also might be better from a soundproofing perspective. I saw this video a couple years ago that claims a dramatic difference: Cellulose vs. FIberglass Insulation Sound Proofing Demonstration. It's done by a cellulose PR group, so you can guess the result... but they seem to have done a decent job of it and there is quite a difference. At least enough for me to think that I'm not giving up anything by going that route.

Quote:
Originally Posted by cw5billwade 
I used spray foam in the attic of my home build and am really pleased with it. In the summer in GA it barely gets above 80 degrees up there. (a different kind of hot from AZ with 100 degrees with 90% humidity) The entire attic is a conditioned space. If your air handler is in the attic I think you should give this some serious thought vise blown in cellulous since you are already putting so much into this build. That would also assist you with the dilemma you were discussing earlier. It would literally pay for itself in a few years in that heat.

My heat pump is actually on the ROOF, directly in the sun. Go figure. That was the thing to do for houses built in the 80s and it would cost more than it's worth to move it now.

I've looked into doing the spray foam route in the attic, but no amount of math could prove to me that it would be even close to cost effective, considering the (relatively cheap) R-50 I had on the ceiling. Yes, the attic does get ungodly hot (160 in the summer), but the R-50 does a good job of tamping that down.

Speaking of heat -- here's what the temp was in my theater space the other day (Apr 21):
108 in April

Since I have no ceiling at the moment, the attic is proving to be a massive radiator. That 108 degrees is at 6ft. It's roughly 115 at 8ft and a balmy 100 at 3ft.
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post #49 of 303 Old 04-24-2014, 06:54 AM
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Man you are going to have to work early in the morning. You do have exhaust fans up there I assume. My house in VA had an exhaust fan in both gables one pulling in and the other blowing it out. It was really nice when I was pulling wires up there last summer with the foam in the attic. Barely broke a sweat.
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post #50 of 303 Old 04-26-2014, 08:02 PM - Thread Starter
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Yeah, you'd think I'd have exhaust fans in the attic... but nope. That's been on my list for some years, but I've never gotten around to installing some. They'd have to be outflow only, since I have a hip roof that doesn't have any space for an incoming fan. A couple of solar powered fans would go a long way.

But as far as sweating goes... that's simply a given. I have fully accepted the fact that no matter what I do, I'm going to be losing gallons of sweat in the coming months. C'est la vie rolleyes.gif
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post #51 of 303 Old 04-27-2014, 07:39 AM
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Man, you certainly need to be careful. That is some dangerous heat.
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post #52 of 303 Old 04-27-2014, 05:55 PM
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Granroth,

I hope you were able to take the advantage of the cooler temperature yesterday and today to get some work done.

Pete
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post #53 of 303 Old 04-27-2014, 10:54 PM - Thread Starter
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I hope you were able to take the advantage of the cooler temperature yesterday and today to get some work done.

Well, I certainly appreciated the chilly weather, but since I'm already resigned to working in the heat, it doesn't actually matter what the temperature is for getting work done. And it's all relative. The temp in the theater space during the day is typically 20 degrees warmer than the outside temp. Since it was 75 today, the temp in the theater was 95. A far cry from 108, but still enough to require fans and a lot of water.
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post #54 of 303 Old 04-27-2014, 11:35 PM - Thread Starter
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Update - Apr 27, 2014

TL;DR - The inner walls are framed!

Okay, so I already posted an entry last week about how I build wall sections, because I figured that maybe that info would be handy for other people wanting to do their own walls. I essentially just did that 12 more times.... some times more easily than others.

I didn't start out on a good foot with the second wall section on Monday. See if you can spot the problems with these two pictures:

Not 24 O.C.Built in place

Yeah, I created several custom spacers so I didn't need to measure any stud distances and then proceeded to use the wrong spacer on my second stud. That is, I used my "first stud" spacer for the second stud, as well... which is too short. Good thing I noticed before I did all the rest! But after I finished that wall, I went to pick it up... and noticed that I had built the new wall around the support for the first wall! Yeesh. Simultaneously raising the wall while moving that support out of the way was trickier than you'd think for one person (no helpers around). Things did pick up a little after that.

The most precise part of building the walls was creating the framing around the two windows. I didn't want to have to shim very much, so I tried to get the framing as exact as possible:

Window framing

Note the lack of any formal header or any jack studs or the like. This goes back to the "advanced framing techniques" that I'm trying to emulate. This method uses fewer studs and since it's not a bearing wall, there's no need to any beefy headers. This particular window was done mostly in place (after raising it) but the next one was done on the floor by just measuring everything very carefully. I thoroughly hate toe-nailing and so I decided that I'd rather do a lot of measuring than have to toe-nail those cripple studs.

Those support boards you see in the above photos worked only so-so at keeping the walls plumb, so I hacked up a slightly more accurate method. I created these blocks:

Plumb block

One half of the block is screwed to the wall and the other half is tacked into the foundation wall. Before tacking to the foundation wall, though, I got out my laser level and made sure the wall was plumb. This mechanism helped keep at least that section of the wall pretty decently plumb as I worked around the room.

After mostly framing two of the walls, I found myself at the point of having to decide once and for all what to do with the "nook" in the corner:

Nook

This was the remnant of a closet that used to be there. I've already talked about that nook as a potential source of noise escaping in a very bad way. In any event, I've had the question of either following the "curves" of the nook with my inner wall or just covering the entire thing up. If I left it as a nook, I'd only have a little less than 14" of width to work with, so putting my A/V rack in there isn't an option. I did consider putting my electrical panel there.. but it doesn't need to be a nook for me to do that. If I covered it entirely over, then it feels like I'm hiding some potentially valuable space. What to do?

Cover up

I covered it up. This was a bit odd for me since if I'm faced with a decision that has equal pros and cons, I'll typically fall back to my original plan. In this case, though, I decided that the ease of building the wall straight overrode my original plan and switched it mid-stream. I guess the extra foot of air space might help out with the soundproofing in that delicate corner, too.

If you look at most of the studs in the photos, you may notice that they look notably darker than those you'd get from a home center or lumber yard. That's because those are mostly reclaimed studs from the deconstruction I did before. For the most part, I was very happy with the results. But there were exceptions. A few of the studs were bowed and fewer yet were both bowed and twisted. I figured that I'd use the bowed and twisted boards in some of the side pieces, since they have a natural 90 degree support structure that should straighten them out (and the nails would keep them straight).

Nope!

Split

It turns out that the old studs are more brittle than new ones and the extra force of the twisted studs was enough to just split along the grain wherever the nails were. I only took only this one picture, but this happened a number of times. I had to quit early that day, after much cursing and throwing of things, since I didn't trust myself to start wreaking stuff. I came back the next day and re-did them all with new (non-twisted!) studs. After that, I still tolerated bowed studs, but twisted studs were verboten!

After a week of work (shortened mildly due to out of town guests), I was at this point:

Framed walls 1Framed walls 2

The inner walls are framed! I do still need to add one more layer of 2x4s on the top as another header to bring the final height to 8' 1-1/2" to match the foundation wall height and to also add a tiny bit of additional rigidity to the mix.

After that, I'll start on the joists (more on that likely in a couple of days). After that, I'll likely take a little construction break and go back to design. I won't be able to do much more without knowing where the electrical goes, and that requires knowing where a heck of a lot of other bits go. I've been purposefully putting off some of the final design decisions but now hitting a hard limit where I need to make some of those decisions.
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post #55 of 303 Old 04-30-2014, 11:20 PM - Thread Starter
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I'm in a bit of a quandary as to what to do for joists. You may have noticed in the periphery of many of my photos that there is a stack of 2x6s that used to be the joists of the previous bedrooms that this space was. Specifically, there are twelve 2x6 joists, each roughly 11' long. There are also a few smaller ones.

I'm trying to re-use as many components of the old rooms as possible, but these particular bits of lumber are problematic from two perspectives. First, they are all too short. The room is almost 14' wide, so they are about a yard short.

Second (and maybe more important), they are 2x6s and not 2x8s. That's a problem because every single span table and span calculator I've used has insisted that 11' or 12' is the max load that a 2x6 should be handling (for 1/360 deflection). So even if I did extend those joists, they would still be too weak.

But... what if I doubled them up? I could stack two joists together and shift them 3' from each other. The two empty spaces on each side could be filled in with smaller 2x6 bits. It could look like this:

doubled up joists

The total size of the combined joist would be 3" x 5-1/2" x 14' (3x5.5 => 4x6). There would be a total of 8' of directly contacting face, with an additional 6' of "filler". I would get roughly 6 joists out of this -- half of the 12 I'll need.

Am I crazy? Will this not work? Is there a better use for these boards? Is there a different way of thinking about this?
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post #56 of 303 Old 05-01-2014, 07:03 PM - Thread Starter
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That's definitely the prudent advice. I'm not always a prudent fellow, though, and tend to try to figure out the "why" in cases. I look at it from the perspective that these are strictly ceiling joists (not floor joists at all) and will have essentially no live load. Looking at the structural properties of lumber, it appears that a 4x6 has a very similar section modulus and moment of inertia as a 2x8. If so, then that implies to me that a 4x6 would work just as well as a 2x8 in that case.

I don't know that, though, since the structural properties tables do assume that it's a solid 4x6 piece and I don't know how sistering two 2x6s would affect those ratings.

Ripping down the boards is definitely an option. I'm traditionally leery of doing so since past experience ripping structural lumber has taught me that there is an awful lot of pent-up tension in quite a few boards. It's absolutely amazing how incredibly much and how fast a stud can twist when it's ripped. I haven't ripped very many 2x6s, though -- mostly 2x4s.

I suppose I could maybe use it while making a stage and/or riser. If the stage ends up being bigger than 6" (somewhat likely) than I can always stack frames.

Hrm.
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post #57 of 303 Old 05-01-2014, 08:15 PM - Thread Starter
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Oh, I agree! I eventually got a structural engineer when I had concerns about my roof. It does no good to take special care in a theater if my roof collapsed due to my incorrect calculations. A ceiling isn't anywhere near as important as a roof (from a structural point of view), but it certainly has the similar negative impact by collapsing. As such, after seeing that 2x6s are never approved as joists for my span, I completely abandoned my original idea of splicing two boards together. I was going to maybe use a half-lap joint or so. Far too unsafe.

The thing is, a 2x6 is perfectly fine for a span that's just less than two feet shorter than my current span. That implies that it's almost okay as-is and that a 2x8 has a lot of room to breath. That further implies that if I create a joist that is even half-way between the strength of a 2x6 and a 2x8, that I'd be fine. Nails are pretty darn strong, though, so I tend to think that a sistered set of 2x6s would be darn close to the properties of a 2x8..

See, I like trying to come up with mathematical or logical reasons for doing non-standard things and then trying to find a compelling reason why I'm wrong. I've found that oftentimes, standards are there only because they are common and not because alternatives might not work as well or better. I'd never expect to see a sistered 2x6 in a span table or calculator since it's just too odd and to unique a configuration. But... span tables are based off of math given the properties of the materials and if my assumptions about my alternative are true, then the math should work out the same. If not, then I'd love to be shown why I'm wrong. And I'm serious that I do love to be proven wrong -- there is no better learning experience than finding out the reasons why you are wrong.

None of that is saying that I'm definitely going to use those joists in that way. There is definite doubt in my mind on some of the assumptions (not sure how nailing affects the structural properties) and besides, it seems like a waste of wood if I could otherwise find a different use for them.
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post #58 of 303 Old 05-02-2014, 01:24 PM
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post #59 of 303 Old 05-04-2014, 11:36 PM - Thread Starter
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Minor Update - May 04, 2014

I finally moved the solar tube from my hallway. I mentioned that a few months ago that the solar tube terminated right where my outside wall was going to be, so I disconnected it and separated it into two halves. The upper half was still connected to the roof and so it was just dangling in the attic all along.

Well, it was time to re-connect it. The first thing to decide was where to put it. I could move it to the hall bathroom, but that would require buying a 4' extension tube for $75. I could move it to the spot in front of the theater door, but that requires buying a 20' extension tube for $35. Or I could move it to right in front of our office door (next to the theater) that wouldn't require buying anything else. I was okay with any of the choices, so I left it up to my wife... who didn't want to spend any money on that setup, so the office solution it was.

Yeah... I did end up regretting that slightly.

First things first, we're now moving past any pleasant weather and so this was what I was dealing with in the attic:

131 degrees

The temperature in the attic is highly dependent on height, so the 149 degrees is if I stood straight up and the 132 degrees was where I was sitting down to work on the hole in the ceiling. The 149 came into play later when I needed to connect the two halves together.

Anyway, the ceiling in the hallway is dropped and it's constructed in such a way that the drywall is connected only to the edges, but have some 2x4s sitting "flat" on the drywall as essentially a screwing surface or for lateral support. I could have fit the 10" hole in between two of the 2x4s, but then it wouldn't have been centered on the office door. Had I known what was about to happen, then I would have not cared about the non-centered aspect at all. Here's what it looks like:

2x4 across the hole

No big deal, right? Just get out the handy sawzall and cut through that board. That's what I thought. But remember that the 2x4 isn't attached to the walls in any way and is ONLY attached to the drywall itself. That meant that as soon as the sawzall blade started moving up and down, it caught on the board and started violently shaking the entire ceiling up and down! Insulation was flying everywhere, dust covered everything, and some of the joint compound on the ceiling started cracking... all in the second or two it took for me to disengage the blade and for it to stop moving. Gah!

That meant going up in the attic and cutting through it by hand, with a hand saw. That's why I mentioned the heat, earlier. See, when it's that hot, you don't "get hot" or "start to sweat" -- you are instantly hot and instantly pouring sweat. I had to kneel on the walls (can't put any weight on the ceiling) and try to cut through that 2x4 with a hand saw with sweat just pouring down and obstructing my vision (I wear glasses) the entire time. I did wise up after the first side and got out my circular saw to finish the two cuts. But man, that was no fun. It looked like this when I was done:

Finally a hole

But remember the reason why I was putting the solar tube where it was? So that we didn't have to spend any more money on an extension? Yeah...., about that:

A gap

There was a four inch gap between the two halves!! After all that PITA, it didn't even fit. Heat makes me more than a little cranky and so that lower half almost didn't survive the moments immediately following my discovery. I had to go cool off, both literally and figuratively.

Well, after all that, I wasn't about to give up. So I marched into the kitchen and got a role of aluminum foil. I doubled a strip up and wrapped it around that gap. I then covered a bunch of it with foil backed HVAC tape. The final look was like so:

Patched

It's a definite hack and far from pretty, but it actually works. We're getting quite a bit of light through that tube now. I'd give a picture of that but I'm not a good enough photographer to take a picture of a bright light source.

Knowing what I know now, I would have definitely ponied up the $75 for the extension and put it in the bathroom. It would have fit like a champ and I could have easily fit the hole between two studs. Ah well.
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post #60 of 303 Old 05-08-2014, 09:11 AM
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Wow! Your attic gets hot. What kind of roof do you have, asphalt or tile shingles? I have tile and I don't think my attics gets as warm. I will have to measure the temp in my attic, and this fall will install a temperature controlled fan and hope it helps reduce the temps.

Regarding your recycled studs I would use them for stage or risers and to avoid them splitting would pr-dril and screw rather than using nails.
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