Please help me to make the best use of this small space!

Hi There, I'm Marc and I'm about to undertake the converting my small single car garage in to a mixing (with a little bit of recording) space. I'd really value your help and guidance. I'm in Cambridge UK and the garage I'm going to be converting is attached to my house. I'm not very loud (I don't like to monitor much about 83dbc and normally wind back to 79dbc or less) but I will occasionally be recording acoustic and electric guitars, vocals and very occasionally a drum kit (if I end up with enough room to fit it in ;-)). I have very little outside environmental noise as I live on a cul-de-sac, so it's pretty peaceful, and there's no lorries booming past or anything. I do want to protect my neighbours from too much sound leakage, although I'm fairly lucky in so far as the ones I'm most concerned about are on the other side of me from where the garage is. My main priority is that the room sounds as good as possible inside, but that it also causes minimum disruption outside. My overall initial budget is around £10,000. You'll see in my (low grade, learning my way through how to draw!) sketch up that I'm really kind of feeling my way in to this, but I've met a cool builder who is interested in helping me to do the work so I'm going to get him to do the structural stuff and I plan to do the fit out myself (hopefully with your help! ;-)) This is why, at the moment, my plan has no roof! I'm hoping to get some tips and advice about what I can do to ensure that I commision the builder to do something that's going to be as useful as possible (both in terms of acoustics and soundproofing) and I'm not wasting too much money. Currently there is an old asbestos concrete room on it which will come off completely and I'm looking to increase the pitch of the roof and cover it with more substantial tiles. I'm a little confused as to the best way to finish this, my assumption is that more volume in the room is a good thing so making the roof space higher will benefit the acoustics but I think it may cause additional problems with the sound proofing? (cf my next enquiriy about MAM and flanking..) Also I could do with some advice about the walls, I've got 2 exterior walls (the one that currently has the garage door in it and the side wall. The side wall is a single brick thick so I've drawn it with an 'inside out' MAM wall infront of it (The building consultant has said that he's happy to see 150mm of rockwool in place of the standard 100mm of Celetex) I've also drawn this in front of the back wall but I don't know if this might be better (from an isloation perspective) as a 2 brick cavity wall? Also, if I've started with the MAM wall do I have to do the whole room this way, or can I have the 2 interior walls (as drawn) with 75mm studs with insulation (the soundproofing back in to the house is less of a concern than the external leakage). Or will this undo my MAM walls by providing a 'flanking path'? I've drawn in the main services also (gas meter and electricity inlet / fusebox) I'm unsure how to keep these accesible whilst mainting a good level of sound containment etc (especially with the gas meter as this is one of the walls that needs to be quiet). Any advice I can get about this would be gratefully received. Finally (for now) I will have the builder fix the floor for me as the old concrete in there is erroding fast, because it's a garage the floor is already a brick high lower than the floor it will 'connect' to though the door so I'm planning to have him take out enough that he can screed it and I can build a floating wooden floor up to the correct hight. How do most people make the gap / join at the doorway work. I'm cool with there being a gap between the floor and the exterior wall all the rest of the way around (cos the studwork will sit on it and hide it) but what happens at the door way? Some sort of gasket I presume? But what? (the lack of floor in my drawing is more that I've not got that far in my sketchup skills rather than my not having put any thought in to it!) I'm reading away wildly, trying to get as much of a handle on this as possible, but I have minimal DIY experience (I've fitted a kitchen and a bathroom before, that's about it) so I'd really appreciate input on the practical considerations, sequencing and elements of the project that a total newb is likely to overlook. Sorry for the long post! I hope I've put all the necessary information in here, such that I can start to get some answers or be prompted in the right direction to find them myself. Many thanks, Marc (Sorry I can't work out how to shrink my SKP to attach it to this post but you can grab it from here: http://www.miwi-music.com/MusicAndMedia ... erials.skp )

welcome! you might read up on the floating floor idea before trying it as a wooden floating floor is not your best option in most cases. if you can get the contractor to separate the newly screed concrete floor from the walls and building that can help although not as much as a fully decoupled floor. you can mix and match isolation walls as long as you're adhering to the double leaf (MSM) approach to avoid triple (or more) leafs and realize that some absorption on the drywall walls will be different than the brick or block walls and could skew the room response. since you're already planning on some drywall type walls, why not just do that all around? just make sure any existing walls are proper to make the final result a double leaf. plan on your ventilation/HVAC from the start to avoid surprises (not the good ones) later.

Hi Marc, and welcome!

I'm not very loud (I don't like to monitor much about 83dbc and normally wind back to 79dbc or less) but I will occasionally be recording acoustic and electric guitars, vocals and very occasionally a drum kit

OK, so for most of that your isolation requirements are not too bad: monitoring, vocals and acoustic guitar are easily do-able, electric guitar a little harder, and of course drums is the hardest of all instruments to isolate.

I have very little outside environmental noise as I live on a cul-de-sac, so it's pretty peaceful, and there's no lorries booming past or anything.

How about nature? Wind, rain, thunder... Or neighbors: dogs, lawnmowers, phones, cars, people yelling at each other...

You'll see in my (low grade, learning my way through how to draw!) sketch up that I'm really kind of feeling my way in to this, but I've met a cool builder who is interested in helping me to do the work so I'm going to get him to do the structural stuff

Does your builder have any experience in building studios? If not, there are a few things that he will need to re-learn. It's not entirely the same as building ordinary houses and offices, and he will need to take some extra precautions when working that he would not normally even need to think about. Even one carelessly placed nail or poorly sealed joint can destroy your entire sound isolation scheme... These things are fundamental for studios, but dont' matter much for houses.

Currently there is an old asbestos concrete room on it which will come off completely and I'm looking to increase the pitch of the roof and cover it with more substantial tiles.

Great! Higher roof is better, acoustically, but does it have to have tiles, or are there other options open to you for roof covering? What type of tiles are we talking about?

my assumption is that more volume in the room is a good thing so making the roof space higher will benefit the acoustics

Absolutely! Height and volume are your friends.

but I think it may cause additional problems with the sound proofing?

Not necessarily. If done right, it could even help! BTW "soundproofing" is a bit of a misnomer: you cannot "soundproof" anything, strictly speaking. Any sufficiently loud sound will be heard on the other side of even your best "soundproofing" wall. Find the best "soundproof" studio in the world, and detonate a few kg of explosives inside: I guarantee that you will hear it quite clearly outside! OK, so that's extreme, but a better term is "isolation" or "attenuation" of sound.

Also, if I've started with the MAM wall do I have to do the whole room this way, or can I have the 2 interior walls (as drawn) with 75mm studs with insulation (the soundproofing back in to the house is less of a concern than the external leakage). Or will this undo my MAM walls by providing a 'flanking path'?

The basic rule with MAM (more correctly called "MSM", for Mass-Spring-Mass) is that you have to do the entire room to the same level, all around. At the very least, all four walls and the ceiling must be done to the same level. I often use the analogy of an aquarium to explain this: If you build an aquarium with glass in two walls, carpet on another wall, paper on the fourth wall, and cardboard for the floor, how well will that hold water? In order to get your aquarium to hold water, you have to put glass on all sides, properly sealed. There are no shortcuts. The same happens with your room: all your walls and your ceiling must be isolated to the same level. You can't do some sides better or worse than others, just because you noticed that the neighbors are closer on that side, or because you started out with a poorer wall on that side. All of them have to end up at the same level. I know that doesn't really answer your question yet, but we'll get back to the way of doing that later, maybe in another post.

I've drawn in the main services also (gas meter and electricity inlet / fusebox) I'm unsure how to keep these accesible whilst mainting a good level of sound containment etc (especially with the gas meter as this is one of the walls that needs to be quiet). Any advice I can get about this would be gratefully received.

The gas meter might need to be moved to an accessible location, and there might even municipal regulations governing that. You should probably check on that. Your builder might know. The fusebox can probably stay where it is and be made accessible through some form of panel. Maybe.

so I'm planning to have him take out enough that he can screed it and I can build a floating wooden floor up to the correct hight.

Like Glenn said, floating your floor is most likely not a good idea. Do it wrong and your will end up worse off (acoustically) than if you had done nothing at all, and it is not easy to do it right. You need to make careful calculations, find the right type of resilient materials, and install everything perfectly. Here's a thread that you should probably take a very close look at, if you are considering floating your floor: Regarding floating floors: viewtopic.php?f=2&t=8173 http://www.nrc-cnrc.gc.ca/obj/irc/doc/p ... /ir802.pdf

Sorry for the long post!

Long posts are good! Really! Take a look at some of mine, if you don't believe me!!! :) - Stuart -

Many thanks for the responses. I think that's quite good news about the floor. I will consider a standard concrete slab with laminate flooring on a good thick layer of underlay.

Great! Higher roof is better, acoustically, but does it have to have tiles, or are there other options open to you for roof covering? What type of tiles are we talking about?

To be honest I don't really know what my options are. I'm assuming the heavier (more massive) the better? The roof will be pitched so I'm not clear how I attach a pitched ceiling to my floating walls (without it pushing the walls over)?

you can mix and match isolation walls as long as you're adhering to the double leaf (MSM) approach to avoid triple (or more) leafs and realize that some absorption on the drywall walls will be different than the brick or block walls and could skew the room response.

Cool, and looking at my plan that is essentially what I've done (once I specify an layer of plasterboard in the right wall) but the outer wall (due to the thermal requirements of the regs has an extra layer of rockwool behind it (which forms the resonator wall packing). On a practical note how should I get my inside out walls in to place? I'm guessing I'll need to build the stud away from the wall (so I can get the plasterboard on to them) and then offer them up to the wall / sit them on their gasket. The builder laughed in a slighly unerving way when I said I'd lift it up in to place once it was built because a 2 x 4m stud wall with 32mm of plasterboard on it is going to be pretty heavy. Ultimately am I going to need to build a more standard stud wall (plasterboard facing in) and build separate treatment? (I'd rather not as I really like the idea of the all-in-one isolation and treatment wall). Also do you have any ideas about how I pin / tack / support the first layer of insulation (the one in the spring) so that it works well and doesn't short out the leaves. Thanks for the input so far I'd also really appreciate some thoughts about the best thing to do with the back wall? All the best, Marc

yes the inside out walls will be heavy to raise. one option is to build it in sections. join the corners using 4x4 and/or 2x6 (if going that size). caulk everything well. the cavity insulation - you can use insulation hooks or mesh to hold it onto the panel, and i've seen construction glue used but i'm not a fan of that.

Wow, I can't believe it's a year since I set out on this project! (don't get your hopes up it's still not done... :-( The main construction has happened. There's a new roof and a pair of deep double glazed windows where the garage door once was. I've now financially recovered enough to want to press on with the next bit, which is the internal walls, and I'm hoping for a bit of help with both thermal and acoustic properties. The building regs guy said I had to make the external walls (currently just a single brick wall) achieve a U-value of .28 (or it may have been .028). For the simplest option of a stud frame stuffed with rockwool and covered with 15mm plasterboard (taped but not skimmed) how much RW6 or Knauf S140 (which I understand to be equivalent) would have have to put in to hit the regs U-value? How much would the acoustic / thermal properties change if I were to use RW3 instead? I've been trying different U-value calculators and had other friends try to help me but I'm still floundering a bit in terms of trying to work out what I've got and what all the elements mean to be able to put the right inputs to the calculators. Many thanks,