Help a young lad with a Shed!?

[GreggWalsh]

Hi there. I have been working in recording studios for 5 years and have an understanding of the recording process and sound isolation. I am after your advice and any help would be so great. I am staying with familly friends and I have had nowhere to set up my small project studio untill recently. I have aquired a new garden shed.

The shed is a Canadian pine, 9by7ft. After spending a few days laying a nice foundation I have got the shed up with roof and new felt etc. It is standing and ready for me to build my small protools project studio for acoustic guitar and voice.

I am in an an area with lots of birds tweeting and planes flying over. I know I cannot get rid of the planes every hour but if I can cut out the birds i will be very happy indeed. This is my goal.

I am happy just to have my own workspace and so any soundproofing I do is a bonus. I am simply building this on the fly with little expense. This is my plan so far (after spending an afternoon checking out prices for materials).

1. I have sealed off the corners and any holes with rubber waterproofing.
2. I aim to use polystyren boards cut to size into the frame of the shed as the first layer (I simply cannot afford the rockwool)- so this is my first big query.
3. I will then layer over this a carpet cut to size. (found in the rubbish refuse site)
4. I want to cover this with asimple thin polythene layer.
5. I aim to put a layer (1.5cm) of cheap plywood on this.
6. I then aimed to do either another layer or polystyren board or perhaps get rockwool here and cover with a cotton sheet (in the hope to add another layer and work as sound absorbtion)
7. Carpet the floor.
8. Add extra door and cover windows from outside.

This is my plan so far. I aim to complete the first layer including the polythene sheet tommorow. Then aim to purchase and cut the board to size.

Do you think i am on the right track. I suppose my biggest concern is the polystyrene replacing the rockwool.

I am aware that a shed is not ideal, ie, it is cold, hot, thin etc but this is the best i have at the moment and I want to get it up and ready as soon as I can.

Could you give me any advice or tips here

Kind regards

Greg

[knightfly]

Greg, been a madhouse here so hope I'm not too late - poly-ANYTHING isn't good for acoustics, period - all closed cell, so no value as absorption, too light so no value for mass. For iso, you need mass-air-mass or else a TON of mass. Nothing else will work, although your bird chirps might be the one exception where multiple leaves with multiple air spaces WOULD work (this helps more for mids/highs, but ruins low frequency isolation)

Carpet is flammable, almost no exception - used between layers of nearly anything else, it will rot, mold, and generally SUCK. It will do this fairly quickly too.

Your layers would put polystyrene on one side of the carpet and polyethylene on the other - two vapor barriers to perfectly contain any and all moisture within the carpet so it can rot as quickly as possible - some of the mold this will produce is TOXIC to humans.

If you have heat in there, you want only ONE vapor barrier and it needs to be the innermost layer other than wallboard - the only other barrier you would want would be an AIR barrier, such as Tyvek (also kind of expensive) just under the siding, but trust me - moisture WILL get in, the only question is if you're going to allow it to DRY or ESCAPE (air flow and/or drainage paths)

I understand the budget thing, but you're heading for a load of crap as near as I can tell... Steve