My Small Shed Studio Plans

This will be my first post on this board but I have lurked and learned so much in the past few months. I have been doing some recording in my untreated room for the last couple of years and I would really like to have a nice Live/Practice/Conrol room to finally do something more than just get my ideas recorded. Now thanks to my tax return I am going to build an outdoor shed from the ground up and want to start narrowing my options down. So here is a little info on my situation. I live in Long Island NY and land is at a premium, my closest neighbor to the site I have drawn out for the shed is about 50 feet away with about 40 of those feet being wooded trees and brush. I live with my uncle who is a retired master carpenter and between the two of us I believe we have all the tools and know how to pull this off. He however knows nothing about acoustics. The shed will be about 30 feet from my house and I can't be waking everyone in the house up.(I usually only have the time to work on music after hours.) Town code states that the largest shed I can build without permits is 140 sq feet.(I don't really have the budget for town permits and inspections.) I would like to mostly use the space to practice with my band and we play metal and hard rock. We'll be using electronic drum set but occasionally a regular set. I also would like to use the space to record, mix, and master and other genres than just rock (electronic,hip hop, experimental.) I am not expecting pro level studio results just something respectable. So here is what I have so far: Please bear with my inaccuracies in sketchup I just started using it 4 days ago. The desk was just a little fun I was messing around with but is where I would like to place it. This is the description of the layers going from the outside in: Cedar shingle wood siding 7/16" OSB sheathing 2x4 wood wall framing stuffed with r-13 insulation 4" air gap ~4" average air gap on the staggered walls 2x4 wood or possibly steel wall frames stuffed with r-13 insulation 5/8" Gypsum Green glue (If budget allows) 5/8" Gypsum For the side walls I want to go with a double leaf wall setup with the inner leafs to be staggered as shown,despite the sketch up file the walls will not be touching.Which leads me to my first question, is staggering the walls the way shown going to hurt the effectiveness of the decoupling, because there are places where the two leafs are closer together? Second question I don't see much use of steel wall framing is there a reason for this? I am looking at it purely from a $$$$ standpoint and there is money to be saved there. This is still very much in the very early stages and I just want to get some solid feedback and start adjusting my design plans so any help would be greatly appreciated.

steel framing has some isolation properties because it is much lighter than wood, but it has much less structural support so you have to go to much heavier steel which then mostly negates the isolation benefit and then also becomes roughly on par with wood anyways... since you have at your disposal a master carpenter, you should be in good shape. if you have not already obtained a copy of Rod Gervais' book http://www.amazon.com/Home-Recording-St ... 143545717X then now is the time to get a copy as it will provide many many of the details you will need and is a reference many of us can readily work from during your construction. on the design - since this is a greenfield project, consider what your priorities are - mixing or live room? both? isolation - if you plan on having loud amps and live drums, then you need isolation. this will require an exterior shell and an inner shell to accomplish, a simple metal shed will not do that. you need space for people to play... you need space for acoustics... something like a 12x20 shed would seem to be a good size for this overall. let's assume you built a 12'x18' (outside dimensions) shed 8' high on the outer walls, 13'h in the peak. you could then build about a 10'6x16'6x7'6h room inside.

"For the side walls I want to go with a double leaf wall setup with the inner leafs to be staggered as shown,despite the sketch up file the walls will not be touching.Which leads me to my first question, is staggering the walls the way shown going to hurt the effectiveness of the decoupling," Yes...you are introducing too many breaks in the assembly that will require support. But is there opportunity that you are trying to incorporate the room treatments and the room isolation? Sure looks that way, and this is not to your advantage. In any event, the entire, from a technical point of reference, assembly is reduced to the smallest dimension when trying to access the isolation value. If you had a wall like the following picture...with wall panels (sheetrock, etc, this would be your room) Then you would treat it according to the known issues of specific dimensions and problem frequencies that become apparent after some testing.

My maximum dimensions for this project are 144 sq. feet by 8 feet high as per town code before I need to get permits and I cannot afford that. As for the metal studs I only intend to use them on the interior shell walls which will only really be supporting there own weight. The exterior frame and support of the shed will be wood. As for the staggered walls If the minimum distance of the air gap is what the isolation is based off the staggered setup will not work for my situation. The idea was to break up some of the reflecting walls in the construction stage but since the isolation is more important at this time, I can always treat the room afterwards. So in that case I'm thinking I will go with standard two leaf setup with about a 4" gap between the inner and outer walls. This will take an even foot (4" stud 4" gap 4"stud) off of my interior floor plan dimensions which isn't to bad considering how tight this is already going to be. So my interior will be 9' l x 13' w x 7 3/4' H.

"8 feet high as per town code before I need to get permits and I cannot afford that. " That height limit is most likely a restriction from your community that you reside in, code is more interested in dollar figures when a permit is or is not required. A permit would cost you in the neighborhood of 50-100 (USD) bucks, which will prove to be less than a percent of your overall cost to build this thing correctly, even with a modest budget. "As for the metal studs I only intend to use them on the interior shell walls which will only really be supporting there own weight. The exterior frame and support of the shed will be wood. " If you build an actual room in a room (box in a box) then the interior metal studs will be supporting a ceiling. The only surface that this room will have in common/share will be the concrete floor. If you do not intend to add mass directly to the exterior walls, you are shooting yourself in the foot, since this is your rooms "first line of attack" against air-borne sound. You have over-stressed 8 feet as your height limit...what kind of roof are you planing for this structure...built-up? roll roofing?

My town code states the structure cannot be more than 8' taller than the surrounding grade. So I may be able to get away with a little by recessing the foundation a bit but there is only so far I can go as I live only about 1/2 a mile from the water. Once I factor in floor joist height plus interior and exterior roof frames and the clouds in I'm really losing this battle so I think I will at the very least need to recess the foundation at least a foot maybe a foot and a half. As for the permits. There is another reason. Basement apartments are illegal on long island, but due to the ridiculous cost of housing here they are a grey area, don't ask don't tell kind of deal. So I am fine unless a town inspector has a reason to come snooping around. :cop: The roof I am not to sure of yet. I was thinking an under layer with the heaviest roofing roll or shingle I can afford for mass. But there will be a price/performance balance here. As for the exterior walls they will be 7/16 OCB sheathing and some fairly heavy pre-assembled cedar shingle siding that is mounted on 3/4" ply. Should I look into adding more mass than that or is it enough? As for the steel framed interior once the double 5/8 gypsum walls are installed the frame will bear the the weight of the weight of the ~500 lb ceiling. And using thicker gauge steel studs for ceiling joists. With a few iso clips connecting the inner and outer leafs for a "just in case"