FINISHED IN 2020! Sharward's Partial Garage Conversion

Hey Stick, I suppose it may be possible to use cleats between the studs to hold two "strips" of drywall firmly against the oposing layer. However, I'm going to go ahead and use OSB, since (don't shoot me 8)) I have 10 foot ceilings and I'll actually be putting up the beef-up panels in two halves -- roughtly 6 feet tall and 4 feet tall, staggering the seams (4 on top, 6 on bottom; 6 on top, 4 on bottom; etc.). This is so that I don't have to worry about 10 foot tall narrow strips of drywall breaking during installation... Plus, I think they'll be generally easier to work with. Finally, the OSB does offer a fair amount of mass for isolation and it offers a differing resonance frequency, so it's not a total waste of money, effort, or space. It's also not too expensive (a little less than double the price of a panel of drywall). The only thing that sucks a bit is that it must be cut with a circular saw on my sheet rack... although I'm getting pretty efficient with that. :twisted: Stick, I'll probably be ripping some more OSB strips and cleating them into my south and west walls next weekend... Let me know if you'd like see the operation live and in person! :) --Keith :mrgreen:

sharward wrote:

Stick, I'll probably be ripping some more OSB strips and cleating them into my south and west walls next weekend... Let me know if you'd like see the operation live and in person! :) --Keith :mrgreen:

Not that I wouldn't LOVE to come and help :wink: , but my Dad is going to be in town to help out with some landscaping projects we're in the midst of: spreading some topsoil, laying sod, planting a hedge, and then he's going to help me attempt to fit what's in the garage now into the rather small shed so that the studio demolition can commence when permits allow... actually, that's a good question for you... am I supposed to have the permit to take the place apart? The outside walls pretty much have to be rebuilt, and getting the ugly 4 inch thick rock off them is going to be a pain the neck (and back, and arms).

Stick wrote:

am I supposed to have the permit to take the place apart?

I don't know the official answer to that, but in my mind, demolition is a part of the project, and since the project shouldn't begin without the permit, nor should the demolition. That's the safe answer. You'd need to ask friendly local bureaucrats to determine the real deal with that. --Keith :mrgreen:

Makes sense. Thanks.

I spent most of the day removing the gypsum from the south and west walls -- 18 linear feet, about as much as the east wall I worked on the last couple of weekends. Unfortunately, I made a not-so-good discovery: there's a layer of OSB that is already attached to the garage side of the south wall! In the back of my mind I was half-way expecting this. It made it more difficult to remove the gypsum, but partway through the job, it occurred to me that removing the OSB is not without consequences -- it's there for seismic stability! :shock: So the plan of removing all of whatever is on the garage side and beefing up the interior wall between the studs (as I will be doing with the south wall) must be changed. :? Here are my options (the first two of which aren't options):

1. Remove the OSB and replace it with diagonal bracing after beefing up the wall between the studs. However, I'm not a fan of this approach, as I believe the OSB is stronger than diagonal bracing. Plus, there are literally hundreds of nails holding the OSB to the studs -- removing it would not be fun. :roll:
2. Remove the gypsum from the interior side (my carpeted office in the house) and beef up the garage side from the interior, then cover the studs with cloth. Nope! Forget it! :evil:
3. Leave the OSB where it is -- add multiple layers of gypsum to it and live with a third leaf effect. I figure three layers of 5/8" with green glue between the final two layers will do the trick. Heck, since I'm not dealing with cleating strips, I might even do four layers of 5/8" in an effort to compensate for leaf #3.

I'm not thrilled about this discovery because it means losing a few precious inches of space in my already tiny room. :roll: At least it's in the direction that I can afford it the most (i.e., not making my room skinnier).

My SW can only do two leaves with 2 material constants per leaf, and only one layer of the second material per leaf; so I calc'd your existing wall using 1/2" OSB one side plus 4 layers 5/8 gypsum, and the office side using 1/2" gypsum, on 2x4's 24" OC - results were m-a-m of 101 hZ - this would be your weak spot. Next, I changed the single gyp side to 4 layers of 5/8 and changed from single stud to double, from 88mm air gap to 300 (12") and recalculated - 27 hZ m-a-m, about 54 dB TL @ 50 hZ, and the dip at 100 hZ is gone. From that, I am "SWAG"ing that you'd be fine with adding 4 layers of gyp to the OSB, then doing your inner wall frame with 4 more - estimated STC of 82 ignoring the third (office) leaf. If anything, you might hear a bit more 100 hZ in the office than without the office side gypsum in place... Steve

Cool. 8) Thanks, Steve. I appreciate the speedy calculations. My, what service -- I post details when I go to sleep, and voila, my answers await me before sunrise! :mrgreen: I should point out that noise levels inside my office are of zero concern to me. However, its adjcent hallway is a concern, so I'm mindful that not having good iso from music room to office is not without its consequences. I wasn't planning to do four layers of gypsum on the inner leaf though. I was figuring on two and probably three layers, over 1/2" OSB of course. Would three layers be alright? FYI, one option I have would be to add a layer of 5/8" to the office wall (third leaf) after the room is completed if it is determined after the fact that I need to lower the resonance frequency of that wall. I would imagine that using green glue on that layer would be a very good thing. Naturally I would only want to do this if absolutely necessary, since we're talking about dismantling a large desk, trimming baseboard, installing the drywall, taping, mudding, texturing, and painting. Even though it's only 100 square feet, that's still a pain. :roll: Bottom line, I'd rather possibly add one extra layer to the office wall than definitely add one extra layer throughout the interior of the room. Makes sense? Now if you'll excuse me, I need to draft a complaint letter to the Institute for Research in Construction why they don't have test results of a three leaf wall with 3 layers of 5/8" gypsum on 1/2" OSB opposite on 2x6 opposite a 2x4 wall with 1/2" OSB and four layers of 5/8" gypsum on one side and 1/2" gypsum on the other... Lazy hosers! :lol: --Keith :mrgreen:

3 x 5/8 gyp each side, + 1/2" OSB one side, double stud, 12" air space - About 51 dB @ 50 hZ, STC 78; your office leaf would still resonate at 100 hZ; if you add more mass to the office side, you'd LOWER the MSM for that part which would make the resulting weak spot HARDER to stop with the rest of the wall; soooo, the good news is that adding another layer to the office side is a BAD idea :lol: Adding a 4th layer to just the inner leaf would raise to STC 80, 53-54 dB at 50 hZ, MINUS the 3-leaf weakness @ 100 hZ... Steve

OK. So, then, I might just go ahead and do four layers on the inside -- 'cuz I want "STC 80" bragging rights! :lol: But we'll see how I feel after three layers -- I might just be ready to call it quits! Thanks again, Steve. Looks like I'll have a little bit of an addendum to submit to the city now.

Check it out -- I have 18 days scheduled off work between now and mid-January (not counting Saturdays & Sundays). I expect to get a lot of work done on my project on those days!! :mrgreen: When January rolls around, I'll probably do the same thing! 8) GREEN = Day Off (Paid) Yeah, I was (kind of) up in your neck of the woods last week, Steve -- but it was a whirlwind trip so I didn't have a chance to get down there and help you 'round the ranch! :roll:

you are a big showoff with all your PTO :evil: :) :) man you will be drumming in no time looks like :) :)

Ha! :twisted: Well, I haven't taken a vacation all year, 'cept for a day or two here and there. Right now I have about 200 hours of PTO. I earn 9.54 hours every two weeks, and for the next three months I'll burn 16 and occasionally 24 hours every two weeks. By mid-January I'll have about 120 PTO hours left. We'll have a new on call schedule out by then, at which point I'll probably schedule another slew of PTO dates. Yet, I still figure that I won't have a "grand opening" until late Winter or early Spring. Maybe that's pessimistic, but I've learned that this project is taking a lot longer than I ever imagined it would. We moved into the house in May 2004, and I honestly figured I'd be up and running with my music room before 2004 ended! :lol: (The water intrusion we suffered certainly didn't help matters any!)

sharward wrote:

Yet, I still figure that I won't have a "grand opening" until late Winter or early Spring.

yeah, 2007 you mean :twisted: sorry you left that open :lol: i wouldnt wish that on ya :)

There'd be some truth to that if I hadn't planned on burning all that PTO! :lol:

I hate TLA's - around these parts, a PTO is part of a tractor, which :evil: would probably now be referred to as a IPD (Implement Pulling Device) :!: :?: :!: :!: :?: :!: :?: :?: :evil:

This weekend I focused my efforts on the west wall in preparation for adding lots of beef! 8) The west wall is adjacent to the laundry room. It's eight feet long and, of course, ten feet tall. There was a slight complication in that there was an outlet on that wall. Actually, the original location was inside the garage. Of course it became necessary to move that outlet to an area where it can be accessed -- it's the GFCI outlet that supplies and protects four other outdoor outlets. (If you're not familiar with GFCI, you can learn about it here.) Many months ago, long before I finalized my plans, I relocated the outlet to the laundry room side of the wall. However, I realized that's not ideal -- I would rather have a totally flat wall and not have to worry about sealing around an electrical box. Plus, it occurred to me that it would be great to have a dedicated outlet for the heat recovery ventilator (hereinafter referred to has "HRV") that will be installed inside the laundry room. So I moved the outlet yet again to the same wall as the door that leads to/from the garage. It's pictured below -- you can see the original location, then the old location (after I moved it the first time), then the new location where it sits today. The red lines indicate the original wiring path, and the blue lines indicate the new wiring path. You'll also see the attic access inside the laundry room. I was fortunate that I was able to do this outlet relocation without having to move my entire body into the attic -- I was able to stand on the top of my 8 foot ladder, supporting myself on the joists around the opening. Note to self: Drilling through a double top-plate with a half-inch blade bit using an underpowered cordless drill while in an awkward position atop an eight foot ladder is not fun! :? I'm pleased with the outcome though. I didn't have to extend the wiring at all -- I had more than enough slack just from the existing wiring. I may improve upon things by extending the circuit downward, moving the GFCI outlet down about three feet, and putting a regular outlet in its place upstream from the current. First, it would be nice to be able to actually reach the GFCI because our pond pumps and lights out back sometimes trip it. It would also be good not to have the ventilator cut of in such an event. You'll also see that the garage side is now covered in OSB strips cleated in with the 1x2s. The only thing I did differently this time was to pre-drill the holes in the cleats. I split so many cleats on the other side. I think I read an account from someone here about the benefit of predrilling holes in the cleats, but I rushed it last time. This time I took the time to predrill, and the result was no split wood! 8) I also went to both Lowe's and Home Depot looking for 4' x 10' drywall. No luck. :evil: They only have 4' x 8' or 4' x 12'. The geometry works better with 4x10s -- less waste. However, I figured out some cutting patterns that would minimize waste and seams, so I'll probably settle for 4x8s later this week. Also pictured below is my revised wall anatomy. On the east and west walls, I'm going to use three strips of 1/2" between the cleats, then I'll top everything off with a layer of 5/8" strips with screws directly into the cleats and green glue in the field. I have more confidence that the last layer of drywall will hold better with the screws directly and deeply into the cleats (and perhaps further, into the studs), versus into the OSB. Hopefully next weekend I'll be done with the east and west wall beef-up! I'm going to hold off on beefing up the south wall (back) where all the contractor graffiti is -- I think I'm better off waiting until my concrete work is complete, because that beef-up will add about 2 1/2" to its thickness and doing the beef-up first might make it difficult to remove the concrete close to that wall. It will be hard enough as it is!! :shock: --Keith :mrgreen:

Here's a close-up of the screw/nail patterns. I plan to use:

• 1" drywall screws on the first layer, straight through into OSB
• 1 1/2" drywall nails* on the second layer, straight through into OSB
• 2" drywall screws on the third layer, straight through into OSB
• 1 5/8" deck screws and/or 2" drywall screws on the fourth layer, at angle into cleats and studs, in addition to green glue.

*The only screws I found that were 1 3/8" were in a huge 25 pound bucket! :-( Speak now or forever hold your peace on this beef-up fastening plan! --Keith :mrgreen:

hi keith, first off, that is some serious beef :D my home depot carries 1 1/2 screws in small boxes. but i had to dig for them (literally had to stick my head and shoulders between the shelves) ... i guess they are popular! i almost didn't find them. just a note, which may not really apply to you, but as a comparison, i am using 5/8 gypsum for the first layer since a 1" screw thru 1/2" drywall will go all the way thru 7/16" OSB and poke out the other side a little. but i note that you have an extra 1/32 inch of OSB and also styrofoam on the other side so this doesn't matter ... right? but on second thought, it might matter, because you may be making a bunch of unnecessary penetrations thru your building paper. just do a "test screw" or two to see what happens. why the OSB on your inside leaf, i'm curious. you can screw everywhere i guess, but this may not be good for bearing the load of the drywall, you may end up with all the load on a few screws that actually are in the studs. also, i don't know if the OSB inside impacts the code requirements as far as fireproofing. i know you have SAFB but something to check up on. dan

Dan Fitzpatrick wrote:

just a note, which may not really apply to you, but as a comparison, i am using 5/8 gypsum for the first layer since a 1" screw thru 1/2" drywall will go all the way thru 7/16" OSB and poke out the other side a little. but i note that you have an extra 1/32 inch of OSB and also styrofoam on the other side so this doesn't matter ... right?

Yeah, I thought of that too. That's why I had hoped to get my hands on 7/8" screws, but I wasn't able to find any. :-( I decided to do 3 layers of 1/2" because that adds up to 1 1/2", the exact depth of my cleats. I suppose I could have done 5/8" + 1/2" + 3/8" to equal 1 1/2", but I wanted to keep things simple.

but on second thought, it might matter, because you may be making a bunch of unnecessary penetrations thru your building paper. just do a "test screw" or two to see what happens.

I'm pretty sure that the OSB isn't quite "one" with the paper behind it. I plan to just "take it easy" with the screws and not countersink them.

why the OSB on your inside leaf, i'm curious.

I figured that's my only method of getting the drywall to stay up. :roll: I have to screw it into something, right?

you can screw everywhere i guess, but this may not be good for bearing the load of the drywall, you may end up with all the load on a few screws that actually are in the studs.

Good point, Dan. Maybe I'll use longer screws (3"?) on the final layer of 5/8" so that it's supported by the cleats and the studs.

also, i don't know if the OSB inside impacts the code requirements as far as fireproofing. i know you have SAFB but something to check up on.

Actually, I don't think it matters, because the area I'm building will become habitable space, so the old firewalls (south and west) will no longer be firewalls. The new firewalls will be the new "L" shaped walls and doors that will extend into the garage space. In any event, while the anatomy of my "beef-up" walls has changed a little bit, the spirit of my plan hasn't changed, and that page of my plan has the fancy little "City of Sacramento Approved" stamp... So I'm banking on it passing inspection. If for some reason it doesn't/won't, I'll know for sure when I get my first concrete form inspection, and in a worst case scenario, I'd have to redo some/all of the beef-up. At least it would still be accessible at that stage. Thanks very much, Dan -- I'm grateful that you've got my back on this. 8) In other news... I just returned from AMS after ordering 26 panels of 4' x 10' drywall panels. 20 of them are 1/2" thick (for the first three layers), and 6 of them are 5/8" thick (for the final layer). Delivery will be $75 (ouch!). (In case anyone's wondering why I didn't do the 75-minute truck rental from Home Depot or Lowe's -- my auto insurance doesn't cover truck rentals, and neither HD or Lowe's offers insurance. :evil:) The square foot price of 5/8" drywall has increased from 25¢ to 30¢ in the past few months! :shock: I expected it to eventually go up in response to Hurricane Katrina (and Rita too), but it looks as though it's starting to happen now. (1/2" is 26¢ now.) Total bill: $378.10, including sales tax, delivery, and fuel charge. Estimated weight is 1,906 pounds. Woo-hoo -- my first ton of materials! :lol: --Keith :mrgreen:

i just realized :oops: that your original wall had OSB facing the inside of the wall, without even any insulation, so i guess it's considered ok to do that.

I think it's the 5/8" drywall that made it firecode. It is (or was) throughout the garage, walls and ceilings alike.

• My original west wall had 5/8" drywall over 3.5" of fiberglass insulation with kraft paper. I removed the drywall and the insulation and cleated in some 15/32" OSB. I will beef up this wall between the studs.
• My original south wall had 5/8" drywall over 3/8" OSB over 3.5" of fiberglass insulation. I removed the drywall only. The OSB is now exposed. I will beef up this wall over the OSB after the concrete work is done.
• My original east wall had 5/8" drywall only. There is 3/8" OSB on the outside of the studs for a short distance heading south. I removed the drywall and cleated in some 15/32" OSB. I will beef up this wall between the studs.

sharward wrote:

The only thing I did differently this time was to pre-drill the holes in the cleats. I split so many cleats on the other side.

Yikes! :shock: I just realized the error of my ways! If I attach my final layer of 5/8 to cleats that are split due to my carelessness, then in theory, the final layer could fall off if the cleats were to break in half! Perhaps I need to replace the cleats that are split, eh? :?

Got your PM, and good thing; you are heading for trouble with your screw plans. You need to keep in mind that ALL screws need to be into STUDS, not just the OSB, and that With that many layers, it's important to have DEEP penetration, especially for the subsequent layers. I would NOT use any screw that gives less than 3/4" penetration into the STUDS for the weight of wall you're building. Because you're building separate frames and insulating well, you don't need to worry about the minor flanking that can happen with screws when using single frames and no RC. Speaking of studs, what's your spacing for the inner 2x6 frame? If not 24", it SHOULD be - see this for a reminder http://forum.studiotips.com/viewtopic.p ... 280e1d399c You'll need a few rolls of masking tape and a few "sharpie" markers, but you WILL need to completely map your screw schedule to avoid collisions from layer to layer. No doubt your "seismic consciousness" will want a full schedule for each layer, which means you need to divide the screw spacing by the number of layers and build a "map" for each layer. This will be almost "surgical" for edges, since schedule calls for 8" spacing at edges PER LAYER. The 12" spacing in the panel's field won't put your fasteners quite so close together, but it's still easy to goof. Simplest way to get this right is to snap chalk lines across each layer in both axes, so you just drive the correct length screws at each intersection. Another biggie - is your old concrete GONE, and the new floor finished? If not, why are you doing drywall? Murphy's law WILL get you on this - if there is ANY way to destroy your new drywall with ANYTHING HEAVY (like chunks of concrete, jackhammers, pry bars slipping, etc, it WILL HAPPEN. The less NEW construction you have in close proximity to any DEMO work, the better. Gotta go weld the muffler back together on my backhoe (pays to watch overhead, especially after dropping a fairly heavy load INSIDE a building and then backing out :? ) and then build a 10x12 sliding door - after which it's time to move everything out of my cramped garage, move everything OUT of my OLD studio and INTO the garage, DEMO the OLD studio, build some more trusses in place, remove 2 more 6x6 poles, pour the remainder of the shop slab (12x48), re-frame/re-side 72 feet of 12' tall wall, dig 200 feet of ditch, lay conduit, re-route and re-wire electric service for dual 200-amp services (house and shop), etc.... (but today I'll settle for the muffler and a working door) STeve

knightfly wrote:

Got your PM, and good thing; you are heading for trouble with your screw plans. You need to keep in mind that ALL screws need to be into STUDS, not just the OSB, and that With that many layers, it's important to have DEEP penetration, especially for the subsequent layers. I would NOT use any screw that gives less than 3/4" penetration into the STUDS for the weight of wall you're building. Because you're building separate frames and insulating well, you don't need to worry about the minor flanking that can happen with screws when using single frames and no RC.

Hold on a minute. You realize we're only talking about outer leaf beef-up strips, right? :roll: I don't want to freak out until I'm sure we're on the same page. And then expect a big-time major freak out! :shock:

Speaking of studs, what's your spacing for the inner 2x6 frame? If not 24", it SHOULD be - see this for a reminder http://forum.studiotips.com/viewtopic.p ... 280e1d399c

Uh, no, I'm planning 16" o.c., as has been on every framing plan I have ever posted on this thread! :evil: Including this one that I posted on August 22:

Another biggie - is your old concrete GONE, and the new floor finished? If not, why are you doing drywall? Murphy's law WILL get you on this - if there is ANY way to destroy your new drywall with ANYTHING HEAVY (like chunks of concrete, jackhammers, pry bars slipping, etc, it WILL HAPPEN.

(sigh) No, the concrete is not gone yet. :roll: I was planning on doing it after my side east and west outer leaf walls were beefed up so that my concrete would stay cleaner. I may go with a decorative covering -- that's why. Not something that I put a lot of thought into though. I didn't think the order of these particular operations mattered much. Please clarify what I'm supposed to do about my beef-up, Steve, and soon -- I'm really starting to freak out here!! :shock: Bummer that my 1,000th post has to be so negative and upsetting... :?

Keith, I can't believe you have made 1000 posts and have only just started!! What have you been doing?? - that's some serious planning my freind!!. I can't see that 16oc or 24oc will make one iota of difference in walls like yours. Those things will stop a missile attack. whats 1-2db between freinds anyway. I hope you don't take/this that the wrong way but it surely won't matter if the studs are at 16 or 24 really in the big scheme of things if you have planned for 16 just stick to it and get on with it!! JG