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Studio in old stone shed? Acoustic and Thermal Treatment
Old 3 weeks ago
  #1
Gear Head
 

Studio in old stone shed? Acoustic and Thermal Treatment

Hi,

I am considering converting an old stone shed with slate roof and concrete floor into an amateur sound studio, mostly for mixing, a single room, no live room. Three walls of the shed are bare stone, with one wall being the gable end of a bungalow.

From what I have read, this will involve dry-lining the room, or possibly creating a floating room. I won't require professional studio-standard soundproofing, as we're in the middle of the countryside, but I'd like to eliminate the sound of passing cars, tractors and also the wind, and contain the noise coming from the speakers.

The roof was renovated recently, but there are lots of large gaps between the wall and the ceiling which need to be built up.

I'm researching the best materials for good thermal and acoustic insulation. So far, Knauf Rockwool RWA45 appears to be a good option, at 40kg/m3, but it's costly.

If the walls and ceiling were dry-lined with this at 100mm, would that make the room reasonably soundproof, and also easy to heat with a small heater? The shed is 14'x10'.

Are there any cheaper options? Budget is small...

I acknowledge there are a lot of variables at play here, but I'm just at the beginning of this project, and trying to assess its viability, and the cost.

There will be no plumbing, but it will have to be wired too.

Thanks for your help!
Old 3 weeks ago
  #2
Lives for gear
 

Quote:
If the walls and ceiling were dry-lined with this at 100mm, would that make the room reasonably soundproof,
Actually, not, it would not. Insulation by itself does not isolate at all. That's a very common misunderstanding of what insulation is, how it works, and what isolation is.

Lining the walls of your place like that would certainly make it sound better in there: it would reduce the reverberation time inside the room, damp some of the modal resonances, and generally improve the acoustic response of the room: what it sounds like inside. But it would do practically nothing to stop sound getting in or out od the room.

Think of it this way: If you spilled water in your kitchen, the a sponge is a really goo way of soaking up that water that splashed around some place where you did not want it. But if you take that same sponge and hold it over the end of the tap with the water running, the sponge does nothing at all to stop the water getting through. That's what insulation is lie for sound: Great for mopping up sound that splashed some place you didn't want it, but no use at all for stopping the sound from getting out. Or in.

Now, that's not the end of the story though! Because if you use insulation as part of a proper isolation wall, then it can greatly increase the isolation. By "proper isolation wall", I'm referring to building what is often called a "room in a room" isolation system. To do that in your case, you would build a stud frame just an inch or two away from the existing stone walls, put drywall on only ONE side of that frame, and fill the entire cavity with insulation. In that case, the insulation does, indeed, greatly improve the isolation, because it then can do what it does best: mopping up sound that went some place it wasn't wanted. Insulation is really good at damping resonances, for example, and the resonances inside the cavity of a wall are what rob it of isolation. So damping those resonances increases isolation.

So, if you need good isolation for your studio, then doing a proper "fully decoupled two-leaf isolation system" would be the way to go. That implies doing both the walls and ceiling in the same manner, as well as the doors and any windows you might want, and also the HVAC system.

Quote:
There will be no plumbing, but it will have to be wired too.
Right. And it will also need HVAC. See this article to find out why: why your studio needs HVAC.


- Stuart -
Old 3 weeks ago
  #3
Gear Head
 

Hi Stuart,

Thanks for your reply.

Quote:
Originally Posted by Soundman2020 View Post
By "proper isolation wall", I'm referring to building what is often called a "room in a room" isolation system. To do that in your case, you would build a stud frame just an inch or two away from the existing stone walls, put drywall on only ONE side of that frame, and fill the entire cavity with insulation. In that case, the insulation does, indeed, greatly improve the isolation.
What you are describing here is what I was referring to, but I may have described it badly. Leave a gap between the stone wall and the new stud wall, fill with 100mm rockwool, cover with ply or another suitable material...and then build similar panels with different cloth for acoustic treatment.

Quote:
Originally Posted by Soundman2020 View Post
Right. And it will also need HVAC. See this article to find out why: why your studio needs HVAC.
Right....that last bit just made things a lot more.complicated. It did occur to me earlier that if the room is fully airtight, that could be a problem...we're not used to AC systems here in Ireland so will have to do a bit more research on that!
Old 3 weeks ago
  #4
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Starlight's Avatar
 

Quote:
Originally Posted by Soundman2020 View Post
Right. And it will also need HVAC. See this article to find out why: why your studio needs HVAC.
Quote:
Originally Posted by cojobt View Post
...we're not used to AC systems here ...
Just be aware that some AC systems include ventilation, others are just AC, meaning they condition the existing air - heat, cool, dehumidify - without introducing any fresh air.
Old 3 weeks ago
  #5
Gear Head
 

A few days of reading into this project, soundproofing techniques, acoustic treatment, HVAC, and my head is collapsing in on itself...

I think I'll just order the skip and empty the shed first of all, then consider all my options.

As neighbouring properties are not a concern, and this space is for mixing (electronic music, mostly in the box) rather than recording live bands, and some vocal recordings, keeping the sound of wind, trees and traffic is more of a concern for me, and staying warm.

At the minute, I'm thinking of going ahead with the external stone wall -- dry wall -- rockwool -- plywood plan, in all walls and ceiling, but I'm stuck on the HVAC.

In terms of heat-generating equipment, I have my iMac, two monitors, two monosynths...most other gear is midi. In the winter months the average external temperature is 8C, spring/early summer it's maybe 12C-16C, and in the height of summer it might get up to 20C-24C for a few days here and there...literally just a few days.

The HVAC info is all very confusing, and while I'd like to get a pro in, I don't know any, and there are none within 150 miles of here. Music production is a hobby, not a career, and I can't justify a few thousand on HVAC.

I've started looking at mini split ideas, as well as passive ventilation.

Somebody suggested having an extractor connected to the open window in the external wall (hole in the stonework), with ducting running to the ceiling of the planned internal drylining/rockwool wall, and a vent in the ceiling, or wherever is practical. That could remove excessive heat, or passively allow ventilation when not switched on.

Yikes. It's complicated. I thought it was all going to be straightforward...and then I started reading Rod Gervais posts and conversations and parts of my brain shrank in fear....

Last edited by cojobt; 3 weeks ago at 01:31 PM..
Old 1 week ago
  #6
Lives for gear
 

Quote:
Originally Posted by cojobt View Post
...Yikes. It's complicated. I thought it was all going to be straightforward...and then I started reading Rod Gervais posts and conversations and parts of my brain shrank in fear....
It is complicated, yes.... but it's not as bad as you might think! It just looks that way at first glance. There's a relatively simple process for figuring it all out. If you take a look at that link that Starlight posted, some of that is explained, and there's more details in related threads there.

Basically, there's two things you need to figure out: your air flow (in terms of "rate" and "velocity"), and your cooling needs. Those are two different and mostly unrelated things. Hence, the term "HVAC". There's the "H" for heating (which you probably won't need much of, but a mini-split can provide it if you do), then there's "V" for ventilation, which is all about air flow rates and velocities and duct diameters, then there's the "AC" for "Air Conditioning", which is basically cooling and dehumidifying rolled into one, because they are closely related.

So. first you figure out how much air flow you need, based on the volume of your room and the number of times per hour you need to replace that entire volume of air (usually 6 or 8 times per hour is fine). That's your air flow rate, usually expressed in CFM for Cubic Feet per Minute. Then use the "rule of thumb" that you should keep the air flow velocity under 300 feet per minute (fpm) at the registers: In other words, at the point where the air comes into the room, and at the point where it leaves the room, it should not be going faster than 300 fpm... because if it goes faster than that, then it makes a noise all by itself, just from moving. It can go faster in the ducts on the other side of your silencer boxes, certainly, but at the points where it enters/leaves the room, keep it under 300 fpm.

Now, with simple math, if you know the flow RATE and the flow VELOCITY, then you can figure out what size duct you need to do that! Because rate is "CUBI FEET per minute", and velocity is "FEET per minute".... divide the rate by the velocity, and your answer is... square feet! Simple! That's the cross-sectional area of the register that you need. Then you can work backwards from there through the silencer boxes, and the ducts... not complicated.


That's the "V" part. For the "AC" part, you just add up the total power consumption of all of your gear, lights, instruments, amps, etc. in watts, add in the heat produced by the people in the room (call it around 200 watts per person to be safe), and the total is your "sensible heat load" in watts. Convert that to BTU (British Thermal Units), and you have the minimum cooling capacity of the mini-split system that you will need. I say "minimum" because there's also the Latent Heat load to consider: that's the amount of humidity in the air in your room. That moisture in the air will condense out as liquid water on the cooling coils inside your mini-split, but that condensation process actually generates heat, which the mini-split must remove. In fact, the heat form the condensation is what the mini-split see FIRST, before it can get to the dealing with the heat in the air... so it's important to get that right. There are tables and equations and graphs and "rules-of-thumb" you can use for estimating the latent heat load in your room. So, add up your latent heat load, and your sensible heat load (all in BTU), and that's how big your mini-split needs to be! If you get a total of, for example, 10,000 BTU, then you would need a mini-split that can handle around 10,000 BTU/hr. mini-splits usually increase in steps of 9,000, 12,000, 18,000, 24,000 BTU, so choose the one that is next highest (don't go down!). Thus, in the hypothetical case that you figured you need 10,000 BTU, you would order a 12,000 btu mini-split. If you are in the USA, then a 12,000 BTUunit is also called a "one ton" unit... not because it weighs a ton! But rather because it cools the same as a ton of ice would... confusing! So a 2 ton unit cools like two tons of ice, which is the same as 24,000 BTU... Sigh! But stick to BTU: it's easier, and you can convert back and forth to watts easily.

So that's it! Your heat load (combination of latent and sensible heat) determines the BTU cooling capacity of the mini-split you need, and the flow rate determines how much air the mini-split needs to be able to move. For most mini-split systems, the air flow is stated as three numbers, which are the low, medium and high fan speed settings. So choose a unit that can move enough air for all your needs on the mid setting, then you can be sure that there's "something in reserve" on the high setting for unexpected extremes (eg, more people than normal in the room, or more gear, or a heat wave), and you can also turn it down to low when you are the only one in there, with only some basic gear turned on.

See? It's not that complicated! Take another look at that article Starlight linked you too, and it should make more sense now.


- Stuart -
Old 1 week ago
  #7
Lives for gear
 
bgood's Avatar
Quote:
Originally Posted by cojobt View Post
Hi,

I am considering converting an old stone shed with slate roof and concrete floor into an amateur sound studio, mostly for mixing, a single room, no live room. Three walls of the shed are bare stone, with one wall being the gable end of a bungalow.

From what I have read, this will involve dry-lining the room, or possibly creating a floating room. I won't require professional studio-standard soundproofing, as we're in the middle of the countryside, but I'd like to eliminate the sound of passing cars, tractors and also the wind, and contain the noise coming from the speakers.

The roof was renovated recently, but there are lots of large gaps between the wall and the ceiling which need to be built up.

I'm researching the best materials for good thermal and acoustic insulation. So far, Knauf Rockwool RWA45 appears to be a good option, at 40kg/m3, but it's costly.

If the walls and ceiling were dry-lined with this at 100mm, would that make the room reasonably soundproof, and also easy to heat with a small heater? The shed is 14'x10'.

Are there any cheaper options? Budget is small...

I acknowledge there are a lot of variables at play here, but I'm just at the beginning of this project, and trying to assess its viability, and the cost.

There will be no plumbing, but it will have to be wired too.

Thanks for your help!
Hey... don’t get too nuts about all of this... you’re not building a pro facility and hosting Coldplay for months long recording sessions.

The advice folks get about this sort of stuff here is usually technically solid (usually) but so far off the crazy meter for what the poster is actually doing with his space.

Do whatever construction you need to make it comfortable and safe (for you and your gear)... make sure you’re getting clean, reliable power and internet (if needed). split AC is fine... a window AC might be just as good and a heck of a lot cheaper... you’ll just have to **** it off when you’re recording with microphones. I picked up a little electric floor heater for my shed build with all sorts of built in safety things (I unplug when not in use) and it keeps my space warm as a womb even in a blizzard. I’ll probably end up going with a split, but, for the three months I need an AC, I throw a window AC unit in... I have to shut it off when I track with mics and will throw a gobo in front of the window to tame any crickets or bird chirps that sneak through...

it’s not a submarine for fuxt sake, don’t worry about whether fresh air is getting in (it is). If you can swing it, install a window or two to catch a nice breeze when it’s blowing and to let in some natural light.

DO plan out some decent room treatment! Panels for the sidewalls, traps for the corners... nice thick traps for a cloud over the mix position.

DONE. Now make music.
Old 1 week ago
  #8
Lives for gear
 
Kyle P. Gushue's Avatar
Quote:
Originally Posted by bgood View Post
Hey... don’t get too nuts about all of this... you’re not building a pro facility and hosting Coldplay for months long recording sessions.

The advice folks get about this sort of stuff here is usually technically solid (usually) but so far off the crazy meter for what the poster is actually doing with his space.

Do whatever construction you need to make it comfortable and safe (for you and your gear)... make sure you’re getting clean, reliable power and internet (if needed). split AC is fine... a window AC might be just as good and a heck of a lot cheaper... you’ll just have to **** it off when you’re recording with microphones. I picked up a little electric floor heater for my shed build with all sorts of built in safety things (I unplug when not in use) and it keeps my space warm as a womb even in a blizzard. I’ll probably end up going with a split, but, for the three months I need an AC, I throw a window AC unit in... I have to shut it off when I track with mics and will throw a gobo in front of the window to tame any crickets or bird chirps that sneak through...

it’s not a submarine for fuxt sake, don’t worry about whether fresh air is getting in (it is). If you can swing it, install a window or two to catch a nice breeze when it’s blowing and to let in some natural light.

DO plan out some decent room treatment! Panels for the sidewalls, traps for the corners... nice thick traps for a cloud over the mix position.

DONE. Now make music.
This is the sort of advice that leaves people with disappointing results, and cost 2x as much to "fix".

Your advice is just broad an unspecific to the OP. A window AC might be fine, it also might not be.

The point of discussing it on a thread is to define a set of needs and reach an efficient solution, based on the needs, expectations, and compromises for the OP.

Your blanket statements are just possible solutions but put the OP no closer to the end, because they are generalized and frankly very "hack".

Now while i am a supporter of guerilla recording methods, and not going any further than necessary, i also support adequate design.

Maybe you don't need fresh air, maybe your studio isn't air tight. Maybe the high energy costs of electric heat don't bother you. But that's no reason to dismiss proper design in general, better designs than yours, and the reasonably good advice given on this thread as "off the crazy meter". Proper design efficiently, and effectively meets the needs of the OP. If your happy with the plethora of compromises involved in your build, great. But don't criticize people interested in more elegant solutions, even if at the end they can't go that route.

It's important to be aware of compromises ahead of time so they are choices, not mistakes.

Studio design and construction is not for the faint of heart, and is not "normal" by everyday standards. This does not mean we should lower ourselves to the lowest common denominator just because that may adequately meet your needs.
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