Soundproofing for rehearsal space/project studio
I am converting a garage/basement into a rehearsal space/project studio.
We won't be playing any very low frequency/loud instruments at all, ever in this space. No bass amps, kick drums etc.
It will be acoustic instruments, vocals, some piano, strings and probably no more than 3 players at a time.
We will be using it to rehearse, record/mix some demos/pre-production stuff and for listening
After playing in residential locations a lot and given the nature of the garage and softness of the music, I've decided that sound insulation is of vital importance.
Here is a floorplan of the garage as is:
Here is roughly what I plan to do:
The garage door is one of those up and over metal doors. I plan on putting in a new wall part way down the garage to split the garage into a small, regular garage and a seperate room.
I plan on putting a door to allow access to this new room from the hallway of the house.
The 'VOID' marked on the original floor plan is actually an empty, closed off room - concrete base and breeze block walls like the garage. The site manager told me that it is closed off simply because of regulations on the development. Apparently, if they had opened it up, the garage would be reclassified as a room and then there are some rules about windows and wall treatments etc...
But, he has assured me there is absolutely no problem with us opening up (after we have bought the house) and doing what we want with it. It is not a supporting wall so should be relatively easy for a builder to do. I plan on having not a door, but a large opening to make it open plan. We couldnt measure the width of the 'void' (cause we cant get in) so my 2.5m is a guess based on dimensions of other rooms.
I've lost my measurement of the ceiling height, but it is somewhere between 2.5-2.8m
So, marked in yellow is the floor space of the room I'll be building.
Above the garage is the living room of the house and the right wall of the garage is shared with next doors garage (it is a semi-detached house with integral garage...)
The back wall of the void is against earth (the house is on a hillside, so the back wall of the 'ground' level is essentially underground), so I would assume no sound insulation is required on this wall.
As the left wall is onto our own hallway, I would assume that relatively little (compared to the new wall and right wall) insulation is required here.
My sole question is how should I approach sound insulation? The key areas I believe will be the wall adjoining next doors garage and the new partition wall.
Keeping sound out is key. The house is on a cul-de-sac so there will be relatively little traffic noise, but likely people chatting next door, and all the leakage through the garage door to keep out with the partition wall. I also dont want the neighbours disturbed...
Obviously, given the size, keeping wall thickness to the minimum required for adequate sound insulation is a must.
I had been looking at wall 'systems' such as this:
but I don't know if this is the way to go?
Finally, how to approach insulating the ceiling?
---------> Nowhere near an expert. I have a few question though, that may or may not be relevant:
Have you considered what the room will sound like from the inside - acoustically - after you've built it? Parameters such as standing waves, phase cancellation, or any other myriad of issues you could face, relative to how the room is designed and built?
Space, Rod and the other resident experts would certainly know way more than I would, but if you manage to get the isolation you seek with proper construction methods designed for such, would you not still want the room to sound good afterwards? Or, at least within the tolerances of where various acoustic treatment methods and materials could be used to effectively treat the space afterwards?
The reason I'm mentioning this, is because there are things you can do in the building phase to head-off potential problems - and I'd think that this would be in your favor towards your ultimate goal?
That being said, obtaining this may or may not be possible, given the area you are working with. And I'm NOT the guy to ask, nor am I qualified to give you any answers, when it comes to that. Again, one of our experts needs to chime in.
The only other suggestion I would make is to provide your measurements as accurately as you can, and try to avoid the "guessing" of dimensions. I can't say unequivocally that leaving out a minor measurement such as a 1" increment would make a difference... but it just might. ;)
You have to consider that what you are doing is about as detail oriented as building a new house....this is not a shed.
Details details details are everything. Your wiring for audio, wiring for electrical devices, fresh air in and out, conditioned air, all these things matter.
What you DO NOT want to do is purchase a wall assembly that is designed to do a thing in a specific environment and your environment be different from that.
Isolation is tricky. It is the by product of a mass/spring/mass system. In terms we can all understand it means there is a wall and an airspace and another wall. There is no hard connection between the two walls...none, not from the electrical or the framing or the HVAC.
What that means to you is that you have part of the puzzle solved...you have an existing exterior hard boundary...the garage. So all you require is an interior boundary designed to meet your isolation requirements based on the mass/spring/mass theory.
But, and this is the tricky part, the system has to be looked at as an entire system. That includes the ceiling and floor. Now a damped concrete floor is considered adequate in this respect but the ceiling is not.
You current 2.5m which is about 8 feet and a few inches is of great importance. Pictures would help solve some of my concerns but in general:
To isolate the ceiling you should mass up the upper floor area from the underneath side. This can be a time consuming task but is a requirement if isolation is part of the goal. You have to consider air conditioning ducts and how they impact this part of the build if at all.
Then you would have to consider if you could install ceiling joists in between the upper floor joist bays and have your new joist sit upon the framed walls of your interior wall assembly.
It also might be a place where using RISC clips and hat track would help you to decouple the upper boundary from the interior boundary helping to maintain the mass/spring/mass assembly you are trying to erect.