John Sayers' Recording Studio Design Forum Archive

I popped into my city's Permit Center today to get some advice prior to making my "official" visit (hopefully next week) to hopefully secure a permit.

I learned that I'm actually dealing with two departments: one is Planning, which ensures that such things as zoning and setback requirements are adhered to (which will be a breeze), and the other is Building, which is where the extra scrutiny will occur.

After a couple of hours at the counter with a building department rep, I became aware of some red flags in my plans:

• The bottom of my outer leaf door is too high. I think I need to either lower the outer door and move the inner door farther inside by another 8-12" to accommodate there being a "non step" plus a step in the space between the doors, or have a 3' x 3' "pad" outside the outer leaf door. As much as I hate the idea of losing any more footage in the room, I'm leaning towards moving the inner leaf door a bit to accommodate the steps between the doors.
  
  I need "fresh air" ventillation. This is because the room is considered "habitable" (even though it is not going to be a bedroom). If this were going to be a shop, it would not need fresh air (e.g., a window). However, because the room is going to be equipped with a permanent air conditioning unit, it cannot be considered an uninhabitable shop. Therefore, I need to have a window (no freakin' way!) or some kind of exhaust/fresh ventillation system. This is quite disappointing, as the only way to do this is to compromise my walls or ceiling. What I was thinking of was an incoming vent that would pull air from the ceiling of a faraway room of the house (I'm thinking the living room) and into the ceiling of the studio, and an outgoing vent that would push air out of the house (I'm thinking the back of the house, an area where the roof peaks and will be close to where my mini split A/C lines will be penetrating the outer back wall). The ducts would make a number of 90-degree turns along the way.

I learned that rockwool is fine as a fire block, provided there are no voids at all. This will be challenging but not impossible.

I also need to provide 1/2" EPDM 60 duro specs that prove its weight limits in PSI and its fire retardance authoritative sources.

Hot mopping is probably not required, but some kind of sealant will be required. I'll need to research this and specify what I will intend to use.

The ventillation objection is significant, and one that has got me rethinking my A/C plan entirely. Recall that my primary purpose of going with the mini-split was to avoid cutting big holes in my ceiling, and here I am cutting big holes in my ceiling anyway. Perhaps there is a way for me to incorporate a combination A/C-and-fresh-air system in the same ducting.

I'm sure there are a bunch of you guys thinking "I told you so!" regarding the "lack of fresh air" drawback of the mini-split.

I'll be giving one of my HVAC guys a call later today to get some advice... Meanwhile, please share any ideas or suggestions you may have.

I talked with one of my mini-split bidders, and here's the recommendation:

• Rough-in the lines for the mini-split system.
  
  Run a two 8" R8 ducts into the room, one for supply and one for return, and tie them directly into the house's existing 5 year old 4-ton HVAC system (which is not multi-zoned). The ducts would have several 90-degree turns to mitigate sound leakage into the house through the HVAC system.
  
  At the thermostat in the hallway of the house, set the fan to "on" (not "auto") when the room is being used, which will ensure constant flow of air into the room (and throughout the house).
  
  If over time it is determined that the room needs an upgrade of cooling capacity, install the mini-split system, using the lines previously roughed in.

What do y'all think?

i can't believe you would ever have need for the mini split system, considering how insulated and airtight your room will be. unless your a/c unit is as wimpy as mine (about as large as a milk crate).

Well, I figured that with a full band in the room with amplifiers cranked up, not to mention my being a wimp in terms of overheating easily, I really fell in love with the idea of being able to control the temperature of the room down to the Fahrenheit degree... not to mention, not cutting gaping holes for ducting.

Maybe the 8" ducts (in and out) will suffice, and the rest can be made up with simple good old-fashioned fans (not the groupie kind ).

Time will tell, assuming I go with that recommendation. Thanks for your thoughts.

oh yeah that makes sense. for some reason i keep picturing just you and your drums in there.

it must be your "lonely drums" avatar. "why am i not being played?? WHY??"

Dan Fitzpatrick wrote:it must be your "lonely drums" avatar. "why am i not being played?? WHY??"

OMG, how did you know that's what they've been saying lately?!

In truth, they've been zipped up in gig bags for about a year now while we (a) prepped our old house for sale, (b) prepped our new house for move-in, (c) moved out of the old house, (d) moved into the new house, (e) finished painting the interior of the new house (f) had a massive water intrusion that forced us out of the old house and into a hotel for about a month, (g) moved back into the new house after $75,000 in repairs, and finally (h) months of planning, which y'all have witnessed most of in this thread!

sharward wrote: I learned that rockwool is fine as a fire block, provided there are no voids at all.

Keith, does this mean that they won't let you use pink fluffy fiberglass insulation or similar in your walls? Or had you already changed that in your plan?

I was hoping to use standard home insulation so i'm curious.

I did not ask specifically whether other types of insulation besides rockwool (a.k.a. "the pink fluffy stuff") would suffice.

That raises a good point about complying with codes and local building department regulations: never assume that what is acceptable for one project by one bureaucrat's interpretation of one city's amendment to that city's adoption of a model code book will be acceptable to your project in your town.

In other words, use what you learn here, and everwhere, to learn what questions to ask your building department.

Your mileage may vary, and (perhaps quite fitting in this case) void where prohibited!

I almost forgot: my building department won't accept a 1/2 schedule screw pattern on the first two layers of drywall, which is discussed at length in this post (and elsewhere). They said: full schedule on all three layers, period. My attempt to politely argue the point was shut down immediately.

(There's something pretty humbling about trying to argue to the building folks why you should be allowed to do something "half way." )

I'm assuming this is not a huge issue... And before anyone suggests it, no, I'm not going to "sneak it in."

sharward wrote:I did not ask specifically whether other types of insulation besides rockwool (a.k.a. "the pink fluffy stuff") would suffice.

but, is the pink fluffy stuff (owens corning) rockwool? i think it is fiberglass right? this is different stuff i think. or am i confused?

roxul's website says it is different, with a much higher melting/burning point.

sorry if i'm being a dork, but if the inspector says rockwool and you use pink fluffy then you may have a problem come inspection time.

dan

Dan Fitzpatrick wrote:

sharward wrote:I did not ask specifically whether other types of insulation besides rockwool (a.k.a. "the pink fluffy stuff") would suffice.

but, is the pink fluffy stuff (owens corning) rockwool? i think it is fiberglass right? this is different stuff i think. or am i confused?

I think you're confused. The pink fluffy stuff is fiberglass. The stuff I'll be using is Roxul AFB which is "made from basalt rock and slag."

Got it, you have decided to use Roxul throughout.

sharward wrote:However, I'm open to changing my plans to incorporate 12v lights and learn about them if there's a compelling reason to do so.

By the way on the subject of cooling, the advantage of using 12v i believe would be they are much cooler than regular incandescent. A few regular bulbs generate a ton of heat. I have installed a 12 volt system for exterior lighting, it's no big deal & i assume the inteior ones youd' use would be the same thing.

Maybe this would help save you from eventually installing the minisplit system.

Thanks very much for the tip, Dan.

Here's a blurb on low voltage lighting:

• Most use the MR16 type of 12 volt halogen bulb. The line voltage (110 volts) of electricity is converted to 12 volts by the use of small rectangular transformers built into each track fixture. There are 4 major benefits when using this type of lighting fixture: 1) Fixtures and bulbs are much smaller than those which use the standard PAR type of halogen. 2) Most of the warmth radiating from the bulb is dissipated to the rear of the bulb (away from what you are lighting). This makes the bulb much cooler and much more comfortable to be near. 3) The third major benefit of these types of fixtures is that the MR16 halogen bulbs that they use give you quite a bit of light for the wattage. For example, a 50 watt MR16 type of halogen will give you the same output of light as a standard incandescent bulb of about 100 watts! Yet another advantage of the low voltage track fixtures is that the MR16 type halogens that they use come in many different wattages and beam angles. You can fine tune where the light is directed to get anything from a small pool of light (great for pedestal tops) to an extra-wide flood beam angle to get a nice wall wash effect. (Source)

Although all of this sounds great, there is the issue of my wanting to have each of my four lighting circuits on 3-way circuits with dimmers at one end of the room. Although this may be possible with a 12-volt system, it may be more complicated and/or expensive.

Fortunately, if I do go with a line voltage setup, I anticpate that I'll almost always have the lights dimmed and/or have some of the circuits turned off, so I'll have much less than 100% engagement of the lights.

I'll have to pay a visit to the Lamps Plus store near us... There's a particular ighting consultant there whose time I'd like to monopolize for a while.

If anyone else has thoughts on this -- especially if you have experience with 12-volt 3-way dimmer circuits -- please jump in!

Does anyone know what sort of EMI/RFI can be expected with 12v lighting? I work at Lowes and walk past that aisle and there's a lot of audible buzz too, although that could be from other things close by, since all the lights are together.

Sword9 wrote:Does anyone know what sort of EMI/RFI can be expected with 12v lighting?

Hi Sam... A little creative Googling on my part turned up this interesting thread for you (and others). Hope that helps!