John Sayers' Recording Studio Design Forum Archive

I'm finally ready to start working!

I picked up the backer rod a few days ago (2.3 cents per foot!!) and 30 sheets of 5/8" drywall arrived today. I've got two friends coming over tomorrow and we're going to start beefing up the outer leaf. I bought just one 850ml tube of Tremco Acoustical caulk to try it out before buying a case. If its just too awful to work with I'll have to figure out another option.

There have been two methods suggested around here for warming up the caulking (in order for it to shoot out more easily) - the microwave was one and soaking the tubes in warm water (wrapped in plastic of course) was the other. I'm not confident enough to put this stuff in our microwave and I'm worried about water leaking in and ruining the cardboard casing so I might try a third option. I'll be setting up a pretty large space heater while I'm working (since its currently the dead of winter) and I'm going to just keep the caulking close enough to it to do the trick (hopefully without it catching fire ). I'll post back about if it works or not.

I'm trying to also think ahead to the next step which is likely sealing up the garage door. The corners on either side of the garage are my biggest concern right now. Since the door is recessed a bit into the garage there are fairly deep cavities created by the framing. Filling it up with solid mass would be pretty difficult (especially on the left side).

What I'd like to do is simply stuff it with insulation and then build framing flush with the door so that I could then simply build a wall on the garage door that extends straight across from one side of the building to the other. This would of course create a 3 leaf system just in the corners and I'd rather not do that, but it seems like the effect may be minimal enough to be acceptable? Or would it maybe not?

Has anyone else dealt with a similar situation? Any recommendations?

This weekend's progress;

I had some awesome help from two friends on Saturday and we ended up getting the entire east wall covered with the first layer of drywall beefup and backer rod. I also spent about half the day today (Sunday) by myself and got pretty much the whole south wall done as well. The pics are from Saturday.

My approach to putting up the drywall and backer rod changed as I worked a bit and wanted to share what I'm doing as I haven't seen anyone else taking this approach. At first I was putting one or two screws in temporarily to hold the drywall in place (with even gaps on all sides) and then trying to squeeze the backer rod in after, then finally adding the finishing nails and removing the temporary screws. But when the gaps were tight it was really tough and time consuming to squeeze the backer rod in. Plus I didn't really want to pierce the drywall with the screws.

So I began to just hold the drywall in the cavity and put the backer rod in with it loose. That allowed me to use a crowbar to move the drywall back and forth within the cavity to make the gaps big enough to easily squeeze in the backer rod. This can be a little tricky with the largest pieces of drywall but makes it FAR easier to install the backer rod.

It felt really good to get started!

P.S. - I'm wondering if anyone has any ideas about what I could possibly do to keep a 'street-friendly' appearance if I removed the garage door? I'd love to just take it down and wall up the opening but the idea of a plain paneled front facing the street is not appealing. Taking it down would also allow me to deal with the deep cavities on either side of the door a lot more easily.

Any thoughts at all are very welcome!

Well, I guess my questions don't have easy answers! But I've got another;

I'm currently installing the 5/8" drywall into the stud cavities of my outer leaf. I had planned on doing both layers in the exact same manner - cut to leave 1/4" gap, fill with backer rod and caulking (per Rod's book). But I'm wondering if on the second layer I should try to not leave the 1/4" gap but cut it to fit snuggly. I would still apply caulking but no backer rod (on the second layer). see pics below;

My understanding is that you only really need one proper seal. Since I'd be putting backer rod and caulk on the first layer that should hopefully ensure that the seal stays true for years to come. And the second layer will have acoustical caulk as well. Wouldn't it be better to extend my mass right to the edge (as much as possible), rather than purposely leaving gaps to be filled by less-dense materials (backer rod & caulking)?

I'm pretty sure the reason you wouldn't want to do this is because as the building shifts and moves it may compress the drywall and possibly break it (and in doing so, also break the seal)? I just hate the idea of purposely leaving big gaps around the edges of my mass!

... rather than purposely leaving gaps to be filled by less-dense materials (backer rod & caulking)?

If I recall correctly, the density of backer rod is about 1/2 that of sheetrock, but the density of caulk is 2x that of sheetrock, so the combined density pretty much matches that of sheetrock, which helps to give an even response, acoustically. But I'm not sure that matters on beefing, since the studs are yet another density. I'm not even sure if you need backer rod for beefing up the outer leaf: for some reason, I have the mental impression that you only need it in the edge-to-edge joint between panels of sheetrock. I don't have Rod's book on hand right now, but I can't seem to recall him using backer rod in beefing up between studs. I think it was just caulk for beef.

I may be wrong, though.

But regardless, my guess is that you could probably do it your way, without backer rod and a smaller gap. However, I would be concerned about it shifting and breaking the seal, especially if you fit it with a really tight fit and no play. I think you do need a bit of a gap around the edge. Morer surface area for the caulk. Better seal.

Yeah, you only NEED one seal, but I'd still go for two: if the only one you have breaks, then you are dead in the water. If one of the two breaks, then you are still in business. Murphy's law rules!



By the way, I don't see your cleats on the diagram. You are going to use cleats, aren't you? I don't think caulk by itself is enough to keep the sheetrock in place securely, and you certainly don't want it falling out once the wall is finished!

Soundman2020 wrote:the density of backer rod is about 1/2 that of sheetrock, but the density of caulk is 2x that of sheetrock, so the combined density pretty much matches that of sheetrock

I went back and checked the spec sheet for the caulking (Tremco Acoustical Sealant) - it is 1720 Kg/m3. I believe the density of drywall is approx. 2312 kg/m3? Can anyone confirm that I'm right about that?

Soundman2020 wrote:I don't have Rod's book on hand right now, but I can't seem to recall him using backer rod in beefing up between studs. I think it was just caulk for beef.

He only addresses beefing up ceiling/floor joists (presuming a basement studio) but he does specify backer rod and caulking for the edges of each layer of 'beef' (page 67)

Soundman2020 wrote: But regardless, my guess is that you could probably do it your way, without backer rod and a smaller gap. However, I would be concerned about it shifting and breaking the seal, especially if you fit it with a really tight fit and no play. I think you do need a bit of a gap around the edge. Morer surface area for the caulk. Better seal.

If the density of the caulking is in fact twice that of the drywall then it really defeats my reasoning for extending the drywall right to the stud, but if the above figures are correct then maybe it would be worth the risk?

Soundman2020 wrote: By the way, I don't see your cleats on the diagram. You are going to use cleats, aren't you? I don't think caulk by itself is enough to keep the sheetrock in place securely, and you certainly don't want it falling out once the wall is finished!

I do plan on using cleats after the 2nd layer of drywall - just didn't include them in the diagram. Although....the finishing nails I ended up using are 2" long and really quite thick. They've got that drywall held on quite securely!

No, the density of drywall is about 700kg/m3.
A regular transparent sealantkit is about 1000 kg/m3 while a coloured (incl. white) weights more than that. For regular kit it's about 1400 kg/m3.

A typical soundsealantkit has MORE mass than a regular kit does and will shrink LESS. A kit HAS to stay flexible.

The point of sealing ALL layers is that you'll NEVER close the gap completely with a tight fitted piece of mass as option 2 describes. To be sure it's COMPLETELY sealed, you need kit. Wood can shrink/expand and therefor leave a gap. The kit will, since it's flexible, still seal the gap. Great isn't it!

The backerrod is only to prevent you from adding too much precious kit into the gap. That's all, nothing more. And since kit is about twice the weight of GB it's fine too have that gap half filled, as Stuart mentioned already.

Just leave a 6mm gap around the mass and use BR+Kit to seal it. You're space is gonna rock!

Hi Ro, thanks for poking your head in here - and for the numbers on drywall. The only numbers I could find online was for raw gypsum mineral, found here;

http://webmineral.com/data/Gypsum.shtml

I'll be sticking with the original plan for sure!

I bought 3 cases of 850ml tubes of Tremco acoustical caulk (36 tubes), which I expect to be just under half of what I'll require in total. As a side note - I think I've done really well with materials costs so far - getting discounts and/or great prices.

Backer Rod - 2.3 cents per foot (regular price)
Drywall - 20% promotional discount from Lowe's ($13.54 per sheet)
Caulking - 10% bulk order discount ($4.91 per 850ml tube)

I also arranged to get the contractors rates for Lowe's deliveries ($20 rather than the usual $75). Lowe's just moved into town this past year, resulting in some healthy competition for Home Depot. The 20% promotion at Lowe's is a one time purchase offer ($100 off a $500 purchase) and is supposed to be only for contractors or those with a Lowe's business account. I may get the next batch of drywall from HD as they offered me a 10% discount.

Anyway - on to some progress;

I did some caulking last night. Tremco says this product is able to perform down to -10ºC. We're right in the middle of an extreme cold weather warning here. It's currently -21ºC!!! I believe that's about -6ºF. I just went out and checked to see how the caulking is hold up - so far it looks perfect.

It can get cold here in Canada, eh?

I just had a conversation with my contractor. They're still putting together numbers but expect to have a quote for me in the next couple days for everything I'd like them to do. He did mention that they priced out a mini-split ductless HVAC system that would include AC, ventilation and heating at approx. $9000-$10 000.

I believe that the heating portion would be a somewhat custom addition to the system. It's actually not really shocking but it is too expensive. I need to stay somewhere between $5000-$6000 if at all possible. The next best option seems to be a mini-split system to handle AC and ventilation and then baseboard heaters inside.

I really didn't want to go with baseboard heaters but I'm not sure what other option is going to be affordable.

I keep on seeing prices like that all over this forum, for simple mini-split systems, and I just don't understand WHY they are so expensive where you guys live! Here in Chile, I can pick up a small 10,000 btu mini-split system, that does both heating and cooling (but not ventilation) at our equivalent of Homedepot, for under US$ 600. A 24,000 btu system would cost me under US$ 900. (That does not include installation, which would cost maybe US$ 150 extra.)

I'm budgeting US$ 1,500 for the entire HVAC system for my studio, including two 12,000 btu mini-splits, ducting, fans, installation, electrics and all, and I expect to get change back on that! But I see folks here talking about prices four or five times higher in other places....

What gives????

So my question is: why are they so cheap here, and so expensive elsewhere? They aren't MADE here in Chile, so that's not it. They are imported. and they are from brand names like General Electric and LG, so it's not cheap Chinese stuff.

So I don't get it! What is the difference?

( If we are talking about the same thing, then maybe I should go into the business of exporting these things to you guys at 100% markup! You could all still save money, and I could finance the construction of my studio! )


- Stuart -

onpurposeproductions wrote: Drywall - 20% promotional discount from Lowe's ($13.54 per sheet)

Wow. That's twice what I'm paying at Lowes for 5/8" 4x8 sheets.

wmtunate wrote:

onpurposeproductions wrote: Drywall - 20% promotional discount from Lowe's ($13.54 per sheet)

Wow. That's twice what I'm paying at Lowes for 5/8" 4x8 sheets.

TWICE?? Canadians pay more for just about everything - don't even get me started on buying pro audio equipment here. If I lived 187 km south of here (across the border) I'd have more money in my pockets.

Soundman2020 wrote:I keep on seeing prices like that all over this forum, for simple mini-split systems, and I just don't understand WHY they are so expensive where you guys live!

Much depends on what's required of course. Below I've linked to a local (to me) mini-split supplier that has pricing. Systems start at $799 but go up to $5095. I expect to need a system with 3 interior units which is at the top of their pricing. The user manual that I downloaded states it has a 'ventilation function' but I'm not clear on whether that means it actually continuously provides the ventilation that would be required for me to breath while I work;

http://www.airlux.ca/products.asp

Hello again!

I've been MIA around here for the past month. Here's why;

I always planned on getting a permit. I knew I'd have to likely jump through some hoops with the town but was pretty confident we'd be able to make it happen - probably a little too confident as there have been challenges..

The main issue that I discovered in speaking with the town is that a detached garage is classified very differently than an attached garage. I had no idea that was the case. Our bylaw only specifies one use for an 'accessory building', which is to park/store vehicles. Of course people do all sorts of things in their garage but to get a permit I would have to meet the letter of the law or apply for a variance (exception) to the related bylaw. Applying for a variance costs $1200.00!! It would take at least 3 or 4 months and I could potentially be denied in the end.

So...the senior planner for the town suggested I consider building a breezeway structure between the house and the garage, effectively making it an attached garage and therefore part of the house. That hopefully should allow me to satisfy the bylaws and get a permit.

Ridiculous - yes. Will I do it? No question. I'll have to think about structure borne noise but I'm not too worried about that. What's more concerning is how quickly the cost of everything is escalating .

Its not all confirmed though. I'm now trying to determine how substantial the structure joining the two needs to be. An unenclosed overpass design (essentially just a roof between the house and garage) would be the cheapest option. But if a fully enclosed design was necessary it would require a poured foundation (which I would make sure didn't connect to the garage foundation) and push the cost up significantly. Although, that would give me an additional shed or workshop area in there.

One thing that I'm pretty sure about is that even if it is fully enclosed there won't be an entrance into either the house or the garage from the breezeway structure. Although it would be nice to not have to go outside to get from the studio to the garage, it just doesn't make sense on either side.

Here are some pics of the current possibilities as viewed from the front of the house. I've pretty much had all work on hold while I figured this out. I think this weekend I'll be back to work!