Dan F's One-Room Garage Studio

Hey Dan, Good to see some posts from you again. BTW aluminum (duct) tape is usual located in home improvement store right next to the heating and air conditioning ducts... it's not in the tape section. I would not trust utility duct tape even through one summer. Bound to fail. I've ducted taped many, many things back together including parts of cars and even a helped duct tape a jet ski back together... BUT heat always seems to be cause of failure AND the PITA is getting all the residue off afterwards. I wouldn't want to try re tape that duct work a year later, with the right type I'd do it now if I still had access. I've been repairing duct work all through my attic and the old tape (not aluminum) is barely hanging on. Marc

Ok Marc, consider it done, dang it ... :evil: thanks though!!

that is indeed an excellent idea to help with the beef-up. I wish you'd thought of it 9 months ago when I was doing mine! :wink: Glad to see you back Dan - we missed you!

He probably did come up with the idea 9 months ago... He just didn't post it until now! :twisted:

bah-dum psht! Good one! :lol:

it WAS a while ago, sorry about that ... better late than never heh? funny Andy i was thinking about you being one of the people who could use this idea, but i was pretty sure you were done with that part by the time i figured that out. good news, we've had some pretty fierce rain yesterday and i did go up and check out my roof penetrations, and no sign of moisture :) also, looking up there it doesn't seem too hard to fix the tape problem.

That's indeed great news about not having any water intrusion, Dan! Congratulations! :-) --Keith :mrgreen:

yesterday i was able to put the proper amount of screws in all of the 1st layer of ceiling drywall, and then caulk everything. man, oh man, that was a lot of caulking, and hard on the neck ... about 200+ feet of caulking, all overhead. yyeeeeeeeaaaaaarrrrgh. i took a tip from our friend in the el dorado hills and put an extra 2x8 i had lying around across two ladders, so i could do virtually the whole 16 foot lenghth of a ceiling bay by just walking along the board. put milk crate next to board so it was easy to step up and down off the board. realized i was missing some critical diameters of backing rod. just ordered a bunch of 1/2 inch and 5/8 inch. not as exciting as a minisplit, maybe, but you know how i feel about backing rod :)

Dan, I'm curious to know if you used backer rod on the edges of your ceiling drywall beef then caulked over top of it, or did you cut your drywall to fit exactly (well, as exactly as possible) between your ceiling joist then caulked (using NO backer rod)? Thanx

Stan, in general I used backer rod. In some cases the fit was too tight, so I couldn't even fit in 1/4 inch rod. But in most cases i had a gap of at least 3/8 inch, or even more. That's what prompted me to order some fatter backing rod today. I found i needed some 1/2 and 5/8, which i had some from Home depot but it's too expensive there. I do believe that the seal will hold up much better over time with backer rod. also, without the rod you will end up using much MUCH more caulk. i realize that you and others may be thinking of the mass differential between caulk and backer rod (which has almost no mass by comparison) ... but i think in this case the integrity of the seal is much more important than the mass. it's my view that the overall, average mass of your construction, plus the airtightness, that determines the TL. not the mass (or density) of any one small area. the backer rod helps the seal to stretch and move without breaking. i will try to get some pictures of my seams up, you will laugh when you see them.

Dan Fitzpatrick wrote:

. . . not as exciting as a minisplit, maybe, but you know how i feel about backing rod :)

:lol: :lol: :lol: :lol: :lol: CLASSIC! :lol: :lol: :lol: :lol: :lol: You are the Backing Rod King! :twisted: I only wish I had the benefit of your wisdom before I used six cases of acoustic sealant for all my outer leaf beef-up... :roll: ...Had I been as smart as you, I would have saved a lot of money and headache and I'd have better seals. I'm hoping my case is so "overkilled" that it my broken beef-up seals hurt me. --Keith :mrgreen:

sharward wrote:

Dan Fitzpatrick wrote:

. . . not as exciting as a minisplit, maybe, but you know how i feel about backing rod :)

:lol: :lol: :lol: :lol: :lol: CLASSIC! :lol: :lol: :lol: :lol: :lol: You are the Backing Rod King! :twisted: I only wish I had the benefit of your wisdom before I used six cases of acoustic sealant for all my outer leaf beef-up... :roll: ...Had I been as smart as you, I would have saved a lot of money and headache and I'd have better seals. I'm hoping my case is so "overkilled" that it my broken beef-up seals hurt me. --Keith :mrgreen:

Six case...holy cow! I went through 2 beefing up my 20x20 garage. How many layers of drywall did you put in between the studs???

Dan Fitzpatrick wrote:

Stan, in general I used backer rod. In some cases the fit was too tight, so I couldn't even fit in 1/4 inch rod. But in most cases i had a gap of at least 3/8 inch, or even more. That's what prompted me to order some fatter backing rod today. I found i needed some 1/2 and 5/8, which i had some from Home depot but it's too expensive there. I do believe that the seal will hold up much better over time with backer rod. also, without the rod you will end up using much MUCH more caulk. i realize that you and others may be thinking of the mass differential between caulk and backer rod (which has almost no mass by comparison) ... but i think in this case the integrity of the seal is much more important than the mass. it's my view that the overall, average mass of your construction, plus the airtightness, that determines the TL. not the mass (or density) of any one small area. the backer rod helps the seal to stretch and move without breaking. i will try to get some pictures of my seams up, you will laugh when you see them.

Dan did you purposely cut the drywall with such large gaps to use the backer rod, or did you figure it was too difficult to cut the pieces to fit as most exact as possible?? Maybe this is why my beef up took so long, because i used a flat rasp and fitted each piece to the studs so that they were friction fitted between the cleats. In the cases were i wasn't so exact i only had maybe less than 1/8" gaps which i filled completely with sealant, let dry, then topped them off again with sealant. On a few occasions i had to use some 1/4" backer rod but it was rare. IMO i just wasn't sure if all that backer rod was going to undermine isolation because of the lack of density...though its not likely alot i didn't like the idea of it. Probably not a big deal huh?

n8nod9it wrote:

Six case...holy cow! I went through 2 beefing up my 20x20 garage. How many layers of drywall did you put in between the studs???

1/2" OSB secured with cleats, three layers of 1/2" drywall secured to the OSB between the cleats, then one layer of 5/8" drywall covering the cleats with screws driven at a 45 degree angle into the cleats and studs. There's Green Glue behind the final layer of drywall applied at about 75% the recommended amount. All of my studs were warped, twisted, or out of plumb. :evil: My gaps ranged from wedged tightly (no gap at all) to 1/2" and perhaps even 5/8" in some spots, even along the same stud. :( I'm hoping the pattern of the OSB (one width), 3 layers of 1/2" drywall (all the same width, slightly narrower to accommodate the cleats), and then the width of the 5/8" drywall over the top (same width as OSB) will make the sealant somewhat redundant. My goal was part seal, part make-up for lack of mass. All of this is covered in detail in my marathon project thread. --Keith :mrgreen:

Dan did you purposely cut the drywall with such large gaps to use the backer rod, or did you figure it was too difficult to cut the pieces to fit as most exact as possible?? Maybe this is why my beef up took so long, because i used a flat rasp and fitted each piece to the studs so that they were friction fitted between the cleats. In the cases were i wasn't so exact i only had maybe less than 1/8" gaps which i filled completely with sealant, let dry, then topped them off again with sealant. On a few occasions i had to use some 1/4" backer rod but it was rare. IMO i just wasn't sure if all that backer rod was going to undermine isolation because of the lack of density...though its not likely alot i didn't like the idea of it. Probably not a big deal huh?

n8nod9it Please take a look at this from the stickies, Knightfly post: Fri Oct 21, 2005 3:19 am. Specifically CaulkBak2.JPG http://www.johnlsayers.com/phpBB2/viewt ... 2948#32948 This is also covered in Rods book. Good place a few have us got bulk backerrod is in above link. Marc

guitardad72 wrote:

Dan did you purposely cut the drywall with such large gaps to use the backer rod, or did you figure it was too difficult to cut the pieces to fit as most exact as possible?? Maybe this is why my beef up took so long, because i used a flat rasp and fitted each piece to the studs so that they were friction fitted between the cleats. In the cases were i wasn't so exact i only had maybe less than 1/8" gaps which i filled completely with sealant, let dry, then topped them off again with sealant. On a few occasions i had to use some 1/4" backer rod but it was rare. IMO i just was going to spend the time to fit it tight and n8nod9it Please take a look at this from the stickies, Knightfly post: Fri Oct 21, 2005 3:19 am. Specifically CaulkBak2.JPG http://www.johnlsayers.com/phpBB2/viewt ... 2948#32948 This is also covered in Rods book. Good place a few have us got bulk backerrod is in above link. Marc

Marc, I have read them thanks :) But it appears that thread is specifically talking about using backer rod on inner wall structures per the diagrams, and not exterior framing ie existing walls as in my garage framing as i was speaking towards. Personally I don't see any reason for using backer rod if your sheetrock is touching the studs (flush fitted). I realize this may not be approached by all because of stud warpage etc...In my case my studs though 30 years old, only deviated 1/4" over an 8' span. Very minimal. As i see it, the integrity of the joint by friction fitting the sheetrock to exact proximity to the stud eliminates any worries about joint shrinkage, because the void is near nothing (but i also did seal anyways in between and over what gaps there were with sc175 as extra precaution). IMO if you can fit the sheetrock tight into the bays with less than 1/8" -1/16"gap then physically you could not backer rod anyways, nor need to because the gap itself if you think about it, is much less physical area than a backer rod filled gap of 3/8" by comparison. The integrity of the seal is maintained by its tight tolerance and fully filling the voids with sealant by a technique of shooting the caulking into the gap to overfill and smoothing it over again a few days later with a light coat of sealant. Yeah it probably would be faster to cut the rock out smaller, and not have to rasp it to fit so close (and not cause alot of my carpel tunnel lol) but i wanted the exterior wall to be homogenous in its construction and the backer rod there just seemed much to area prone for TL to escape. Thats why i took the extra time to fit it so tight. Honestly, I'm not trying to re-write whats common knowledge of backer rod use, the use of backer rod is important, i understand its use, and i understand it very much so helps to maintain gap integrity in voids of certain widths. I plan on using lots and lots of backer rod for my inner walls..lol !! And i may be totally wrong on all of this!! haha BUt...i'm not sweating it and if you use backer rod on your beef up i think thats fine and great as well! :wink:

This is a really interesting point of discussion... It's not so much a "to use or not to use backer rod," but rather, "to leave or not to leave a gap that would then require backer rod." It seems to me that a tight-fitting piece of beef-up drywall against a stud or a joist with a bead of acoustic sealant where the two meet would create a two-sided bond -- definitely not the dreaded three-sided bond that backer rod is supposed to help be maintained over time. While I'm inclined to think that's acceptable, and perhaps even superior to a joint that requires backer rod, I'm left wondering if there may be a risk of further warpage or twisting, or even seasonal swelling, of the framing members that would cause the edges of the gypsum strips to be compressed, or worse, parts of them to buckle, under the lateral forces. If that were to happen, then I would think the seal would be the first to go. That does double or even triple for an earthquake event -- even a minor one that causes no noticable structural damage anywhere. This is all just theoretical, just as so many other ccpncepts described here... I'm not claiming expertise on this, but I do want to at least provide food for thought and/or further discussion. It makes some sense having this all taking place in The Backer Rod Czar's thread... ;-) ...But I may exercise my awesome moderator powers at some point by moving this series of posts to the aforementioned thread, or perhaps splitting it off into a new thread entirely... Meanwhile, assuming Dan will indulge us, carry on!!! :-D --Keith :mrgreen:

Man...this is "JUST" in time for me... I was going to begin my beef up in about 2 weeks. I have read different opinions about whether or not to use backer rod for beefing up a ceiling joist cavity or a wall cavity. Hopefully I'll have an answer by the time my "crew" comes in to do my ceiling and walls. I've got an :shock: on this topic fellas... Thanx!

n8nod9it wrote:

Dan did you purposely cut the drywall with such large gaps to use the backer rod, or did you figure it was too difficult to cut the pieces to fit as most exact as possible?? Maybe this is why my beef up took so long, because i used a flat rasp and fitted each piece to the studs so that they were friction fitted between the cleats. In the cases were i wasn't so exact i only had maybe less than 1/8" gaps which i filled completely with sealant, let dry, then topped them off again with sealant. On a few occasions i had to use some 1/4" backer rod but it was rare. IMO i just wasn't sure if all that backer rod was going to undermine isolation because of the lack of density...though its not likely alot i didn't like the idea of it. Probably not a big deal huh?

n8nod9it, in my small experience you need to cut drywall about 1/2 inch shorter than your gap, so you have 1/4 inch gap all around. this is becuase if you cut it exact, you will (as you found out) have a tough time fitting the piece in. your stud bays are not going to be perfectly square of course. but, i think the way you did it is probably fine, although a lot more work. but i will say that in my mind, i have been thinking that the areas where i cannot fit backer rod, i was a little disappointed. my feeling is that the caulk will not penetrate a small crack very well, so you will get an apparent seal on the surface that may not be that great. keep in mind, soundproofing is done all the time in the real world by real contractors under real world conditions. i guarantee you they are not micro-fitting each piece of drywall, they are leaving a gap and then filling it with backer rod. now, maybe the way you did it is better, but i'm perfectly satisfied with following industry practice. in general, standard practices i believe have evolved to provide the best effectiveness at the lowest possible cost (most of that cost being TIME, not materials). personally i'm trying to get my project done this century :) all that being said, i get really annoyed when my gaps are bigger than 3/8 inch. but sometimes it just happens. the good news is since i'm doing two layers, hopefully i won't have two layers with huge gaps right in line with each other. Dan

Hmmm, I'm going to use backer rod and caulk in gaps if all beef up. Not to say an almost exactly cut piece of drywall for a stud bay with caulk in 1/16th or so gaps would be better or worse. Even though we may never know which way will hold better over time, we do know creating a 3 sided caulk joint is not good and using not suggested unproven methods is also not good. Seems like 1/16th gap caulked should hold BUT: -May be a little but more expensive with backer rod and 1/4" gaps. -Should be less messy not having all the drywall dust from rasping. -Should be quicker with 1/4" gaps, not having to custom rasp each piece of drywall. n8nod9it, IF I were you and did what you just did I would not tear it out to redo it, although new pieces yet to go in I would change to the 1/4" gap. Just my opinion. Marc

And I'm the coolest guy ever to have actually met the previous two posters in real life. :twisted: Sorry... Couldn't resist myself... :P

POints taken guys, however i am nearly done with the beef up of my exterior walls...just 2 more to go (I probably have over 100 hours or more into just the beef up). But I have the time currently to devote to it 24/7 if i wish.. even then its easy to burn out on it. :wink: Today i decide to take off and work on my motorcycle which the weather has me jonesing to ride. Regardless, in my case, like i mentioned my stud bays were rather strait and plumb, unusual i guess. Two things about the joints. The joints i made were less than 1/16 in most cases. Most cases gap is non existant. This wasn't all rasping the edges, but careful measuring between the studs in 5 places allowed me to get the first attempts to fit very close. (I think actually most of my wrist pain was not from rasping but from using the utility knife and just the cumalitve effects of all the construction work i'm doing as a whole). But, most of the rasping was because when you break a sheet you sometimes get irregular lumps on the edges that need to be sanded off to get a nice flat "jointer style" face. But i did rasp my fair share. Drywall work is dirty no matter how you cut it, but i used a rasp with a catch area made into it which i emptied regularly. Still though, when i did have much irregularity, and in some spots i did, i used backer rod...overall less than about 10 feets worth in the whole thing. Marc, i understand your points, and to contractors time=money. So that has to be factored into their decision to cut to rough and not exact dimensions (drywall fitting). Second point, one can inject the caulk deep into a joint and completely fill it, or overfill it, while running the gun down the length of the board, it just takes some practice and patience. You have to cut the tip a certain way, and you will use more caulk if you had large gaps...In my case, i used about 2 cases though...maybe 26 tubes. All in all not that bad or expensive in the big picture. I think Sharwards thoughts on the structure shifting and breaking the drywall has the most importance in an extreme event (ie earthquake), and i did think of that living in Cali, however i also went to USGS to see that where i live is not on any faults or historic events where my structure would be possibly comprimised. Lastly, I also caulked all layers. Initially i was going to just caulk the final layer, but i caulked the OSB, and the sheetrock layers, so there may be some additional protections there. But yeah, Sharward has it right when he said, " It's not so much a "to use or not to use backer rod," but rather, "to leave or not to leave a gap that would then require backer rod."... I think its a case by case thing which depends on those things discussed and let each builder figure out which works for them. Its not one way is better for me, or one worse on this one issue...i think both paths will work fine.

sharward wrote:

And I'm the coolest guy ever to have actually met the previous two posters in real life. :twisted: Sorry... Couldn't resist myself... :P

We haven't met but you are practically the Fonz, Sharward..heh

Oh and i have to tell ya'll my wife thinks i am the biggest nerd because she read what i was posting about backer rod and the whole discussion and can't believe i post on a forum about caulk. I just said be glad its that type of caulk i am chatting about! hahah!

Just respond to the wife, "Honey, you do want me to know how to use my caulk, don't you?" :P Self portrait...