Part 1: the Magical Floating Floor
It all sounds very mystical - a room and floor magically floating, isolated away from any contact from the outside world. I kept thinking about Magneto's prison in X-Men. This article is more of a picture book of the floating floor that we built in my the live room of the studio here at Revolution Audio Recording in Mississauga, Ontario, Canada.
There are many ways to build a floating floor. I went to some extremes, but large budget studios would go much further than I did. I would consider this a mid-cost, home recording studio floating floor, suitable to put on any level of a house or commercial building with a little bit of headroom. The floating floor (only - not the hardwood on top) cost me around $800 CAD for 160 SF, or about $5 sf + labour. A bigger budget floating floor might cost 10 times as much or more and include hundreds of pounds of cement and high gauge metal springs - this floors are amazing, but are not for the typical home recording studio (or typical house construction!). Why a floating floor, you might ask? The main purpose is to create a room which is isolated from the rest of the building/environment around it.
Isolation, and specifically the method of "decoupling," is the key to reducing the sound levels traveling into and out of a room. Notice that I didn't say "sound proof" a room. There really is no such thing. In building a room, however, you can determine what the loudest sound will be in the room and then respond accordingly as it fits into your budget and space constraints. I determined that I wanted a live room that I could record drums in any time of the day or night without disturbing my neighbours to the left and right (a Hearing specialist on one side, oddly enough) and the other people living about the stores in the building. I determined that I was looking to build a room with an STC rating (sound transmission class) of around 62 to bring the drum level down to a reasonable level.
To achieve a target STC of 62 I had to plan and build to some considerable length, the details of which I may get to in a later article, but which included the purpose of this article: A room floating inside a room - basically an exterior shell, secured to the rest of the building and a room built inside upon a floating floor, none of which is secured to the building - the only real contact points being the floating floor. Below is the picture book showing the details of the first step, the floating floor.
Stay tuned for further articles on such fun subjects as soundproofing (so called), double walls, make-shift iso vocal booths and sound treatment vs. sound isolation in the studio.
The pre-existing floor looking towards the back room
The neoprene pad comes in a 2 X 2 foot size which we must cut down to 2 X 2 inches. This one is weighted for up to 25 psi
These straight edged tin snips are handy...
Cutting the squares
The two inch neoprene square.
First using the paint thinner to clean each 2 X 2 pad, we then use the contact cement to glue them together 3 at a time.
This part reminded me of a good old craft time
The finished neoprene sandwiches (or pucks as I'll call them)
The pucks are scattered on the floor. We figured out the weight distribution and to weigh each puck down about 15 lbs. for maximum elasticity, we used 76 pucks.
Ewen (with no head) and the pucks
We decided to put half thickness of safe n' sound insulation around the pucks to avoid any hollow sound to the floor. Ewen is using an exacto knife to cut them in - we don't want the floor resting on the insulation, or anything else except the pucks.
Side view of layer # 1 going down.
Layer #1: Tongue and Groove Plywood/ OSB resting on the pucks (not secured down, only resting on top)
Layer #1 finished
Putting down layer #2: 5/8 firecode drywall
Layer #2 finished - we put a few screws in to help secure the tongue and groove floor beneath it.
We built a box around the floor vent to allow the floor to float around it rather than resting on it.
Layer #3 - another plywood tongue and groove (OSB)
Ewen putting in the final underfloor piece. My final hardwood floor with underpadding will lay onto this floating floor (pictures to come...)
Side view of the new floating floor - from the bottom there is the puck surrounded by insulation, then T & G plywood, then 5/8 drywall then another layer of T & G
