im confused about Wall structure (HELP)

Ok guys.. im a newbie and im a lil confused... As ive been reading about wall structure i understand that to get the best results you need a 2 leaf system.. I just wasnt sure how i would approach this in my situation... im currently in the process of ordering insulation but i have a couple of questions... the size of my control room is 12x10x8... i have 2 exsisting walls one is just sheet rock and the other is has solid rock behind it... My question is.. am i building a 2 leaf system over the current walls that exist... or am i ripping out sheet rock insulating and then building another leaf on top ... to my understanding the wall that has brick behind it would be a pretty good first leaf( correct me if im wrong). also if im using a 2 leaf system i am going to need double the insluation right? and if i need double the insulation can i use 2 different types. ie rockwool and pink stuff... i added a picture so you guys can see ..the wall in fron is just sheetrock and the wall to the right has the brick behind it....If anybody can please help clarify some of my questions for me it would be a great help!!!! thank you

I believe that your rock-wall (plaster over the rock, or drywall?) would certainly be an excellent first leaf. Leave a gap and frame a new wall in front of it. For the hollow wall with the door, I think your best bet is to remove the existing drywall on the inside of the room, then frame a new wall in front of that. Insulate both leaves, but leave an air gap between the insulation. From my understanding, the insulation is more to dampen resonances in the drywall than to actually insulate, especially from a sound point of view. To that effect, the rockwool/703 has been established as "best" and the fluffy pink stuff has been described as "a big pain to deal with". The pink stuff will compress more easily, which reduces its effectiveness as a damper, and the paper backing will need to be removed. Apparently, the paper itself can act as a third leaf, and weaken the STC of the wall somewhat. Oh, and I want to make a disclaimer - my advice above comes from what I've learned reading this forum, not actual construction experience as many others bring to the table. You may want to wait till someone confirms or refutes my advice before acting on it. MPEDrummer

thanks for replying.. ill wait for a conformation like you said....i was thinkingalong those lines also.

thanks for replying.. ill wait for a conformation like you said....i was thinkingalong those lines also.

Hey King-I, I have looked at your thread in the Studio Design forum as well as this thread. Congratulations on your home purchase. 8) I know you're itching to get started on this project, but trust me -- while I can relate to the "I just got the new place and I'm ready to build ASAP" syndrome from which you are suffering, you have to slow down. You will not regret waiting until you fully understand what you need to do before executing, but you will regret starting too soon. There are many threads here from folks who painted themselves into corners going too fast. I see several challenges: Your being in a multi-family dwelling (a townhouse with neighbors on both sides) and having probably zero room to spare overhead with a 7' 6" vertical clearance are at the top of the list. While it may seem that basements are ideal places for studios, they do have their disadvantages. The potential for water intrusion is probably the most significant one. I had a $75,000 plumbing disaster in our home two years ago. Trust me -- you never want to deal with water damage, especially slow intrusions that cause mold to fester. Please carefully review Luftweg's "Basement studio-room project in Boston area" thread" and "Andy_Eade's Rotten Basement Conversion Thread" threads to get a sense of what kinds of things can go wrong and how best to deal with and design around them. Your budget seems pretty small to me. Granted, the space itself is small. Maybe it will be enough. That depends on how much isolation you're really going for. But if you have to buy HVAC equipment, I'm betting you'll need more money. You almost certainly will need a building permit for this project. Don't miss this thread. Your limited vertical clearance may disqualify your space from doing what you hope to do. :roll: Contact your local building department to determine the minimum vertical clearance you must have for a basement finishing project. Be sure to read Rod's book cover-to-cover, frontwards and backwards. There will be a quiz. ;-) I learned so much prior to Rod's book being published just by reading threads on this forum, over and over, for months. You jumped very quickly on designing your space, but you're stumbling on construction details. That's because designing it is a lot more fun than figuring out how to build it! :lol: Allow yourself the requisite amount of time to ramp up your knowledge in this area. Doing so will pay off big-time and failure to do so will cost you big-time. That's all I have for now. Good luck. Keep us posted -- especially with your legal height limit. (Unfortunately, my prediction is that 7' 6" is the minimum, which is why your place was built to that standard. :() --Keith :mrgreen:

hay sharward thanks for the reply...Currently i have changed up the size of the design..and i have uped my spending limit tremedously im at about $8,000 us...I bought Rod's book and read it twice... currently the design is a 12x10x7.5 control room and 6x6x7.5 iso booth...(ill post skecthup later).. I got an estimate from Hvac already but i am seriously considering using an exchange room desgin with a through the wall ac.. I will have to check on my height permit though.. im not sure what the limit is... (if the limit is what i am at now what suggestions would you make as far as soundproofing the ceiling with out breaking violation? I have concrete slab with earth on the bottom so i am going to leave my floors at that...in the above post you see my wall situations. i am trying to achieve a control room that will give me great acoustics and good soundproofing... Im working with limited space so my situation for mass is little challenging... so if you or any one else can help with a lil more clarification it would be greatly appreciated... I have a contractor building it for me and i just want to make sure that he clearly understands what i want .. so thats why im hear getting some clarification... i am still doing my reasearch but still kinda un sure if im going in the right direction... theres alot of information and it gets overwhelming sometimes with all the different situations a challenges of everybodys studio... some rules can be bent and somecan not.. so im justhere trying to find those definites... anyway thanks again for checkin me out.. if you have some input on my earlier post just drop by when u have a chance....

You may be able to use the "chiller room" method for cooling, but I don't think you can use that method for fresh air supply. All of the code language I have seen on mechanical fresh air ventilation (required when you have no operable windows!) is that the air must come directly from the outdoors without another room acting as a "middle man." :roll: Here is an example of one city's paraphrased interpretation of mechanical ventilation requirements for habitable space, based on their adoption of 2003 International Residential Code. Your municipality may vary. Void where prohibited. Past performance not indicative of future results. One at this price. No warranties expressed or implied. ;-) (As an example, my city's model codes require about 50% more fresh air capacity than Boise's does.) Consider an energy recovery ventilator (ERC), such as the Fantech SE704N, for your fresh air requirements. You can equip it with a wall control. --Keith :mrgreen:

sharward wrote:

You may be able to use the "chiller room" method for cooling, but I don't think you can use that method for fresh air supply. All of the code language I have seen on mechanical fresh air ventilation (required when you have no operable windows!) is that the air must come directly from the outdoors without another room acting as a "middle man." :roll:

Shar, boy did someone really screw up when they read that one and interpereted it.. That is not what it says at all. The reference that states: "Natural Ventilation shall be through windows, doors or louvers or other approved openings to the outdoor air" only applies to a direct connection to the outdoor air when the method of obtaining air is taken directly through the room wall AND the fresh air supply is a passive system - not a mechanical system (which is why a minimum net free opening (as a percentage of the room area) is required. Exception 1 clearly allows for other methods of obtaining fresh air within a room that does not have to do with a direct connection to the outside from within that room space. It is commom practice to provide plenums within rooms and above ceilings for the purpose of moving fresh air throughout buildings. They specifically allow for mechanical systems that don't meet the general requirements noted above - one of which is a direct connection from that space to the outside world. The "Adjoining Rooms" section only has to do with providing air (and light) from an adjoining room without the use of mechanical means - at which point they proscribe a minimum net free opening and minimum room size for connection to the adjoining room. Sorry my friend - I would have challenged them on that one and won - they really did screw it up. Using an adjacent room as a fresh air plenum is legit as long as you can maintain the minimum requirements set for that fresh air........ The only room you could not pull fresh air from would be a bathroom - or any other space where the air is considered contaminated and an exhaust system is specifically required for the air in the space. Sincerely, Rod

Thanks for the clarification, Rod! 8) At one point in my project I considered an air cycling system that would have involved two ducts -- one "pushing" and one "pulling" -- forcing air between my studio and a room in our house -- similar to your illustration, but not from an adjoining room. However, I nixed that idea pretty quickly. I honestly can't remember if I approached my city's building department on that idea or not. I don't even find anything in my monster thread about it... :roll:

Rod Gervais wrote:

Using an adjacent room as a fresh air plenum is legit as long as you can maintain the minimum requirements set for that fresh air........

So... How does one go about measuring the amount of fresh air in terms of air changes per hour (ACH) when the room being used for the exchange is getting a mix of fresh air and non? Or does that part of code not apply in that case? --Keith :mrgreen:

Great questions Keith!!