John Sayers' Recording Studio Design Forum Archive

Here is some general background on myself and my project. A few somewhat specific questions are at the bottom.

First some general information. For a number years I have working out of a converted bedroom for my studio. It has served as well as a small space can for practice, recording, mixing, etc. We all know the story – modal issues, ringing, reflections, reverb times, low ceiling, almost square dimensions, big window, hollow core door, crowded space, yada, yada, yada. Basically, physics works, and not always for you. I have it pretty well set up for what it is, but it is now time to move up.

I am mainly a guitar/bass player who does occasional drum, keyboard, and vocal parts. Anticipated volume levels range from quiet solo jazz guitar and ukulele to dimed amps and full 4 piece rock groups. Simple guess is 40 or 50 dB to 100+ for recording/practice. I generally mix in the mid 80s and lower. I forget who wrote the book on mixing levels but I follow it. I think he recommended 83dB (maybe it was 73) at the mix position. I will have to look and post a link later. It is an excellent read.

Goals are great sounding rooms, sound isolation both from outside noise into the studio and from inside the studio to the rest of the house and my neighbors 20+ feet away. Pretty much what all of us are looking for.

Time frame is a couple of years. Budget is sufficient to build out this space.

Later this year, family and all will be moving into a house that is being built. One great feature is that it will have a full unfinished basement, in which I intend to use a portion of to build out a studio with control/mix room, live room, and vocal booth.

Some things that I currently know about the basement space (and would appreciate and comment on) are that

1) I will be meeting to review the basement plans with the builder within the week;

2) There is a fair amount of space to work with - on the order of 20' x 40' (edited dimensions after review of basement plan, see below), possibly more depending on layout and how the rest of the basement will be used and I will have some ability to shift the space around within the overall basement footprint;

3) The basement floor to the bottoms of the joists above is supposed to be at least 11 ft. I am guessing that I can get 9 to 10 foot ceilings in the built out space;

4) The floor above will be (basement upwards) joists with pink insulation between them, a subfloor of some sort and then either padding and carpet, bathroom tile, or hardwood, depending on the room above;

5) In the basement there is to be a mechanical room to house the furnace, evaporator, and air handler for a split HVAC for the main floor with space for an additional one for the basement, including the studio. The location and size is to be determined. I have never dealt with this kind of setup before only having the big package units outside the house;

6) The duct work from the mechanical room to the main floor vents will be the flexible kind (I believe). Size and where it will be run are unknown;

7) The floor and a portion of the basement wall height will be poured concrete, with rest being stick and frame and all standard brick exterior;

8) There is intended to be a separate electrical subpanel only for the studio; and

9) There will be a number of steel posts to support the span of the joists (in the most inconvenient of locations I am sure). I may have some say in positioning them but there are two potential issues a) there may be additional cost involved to beef up joists, etc. and b) since I have not sited the studio in the basement yet, I would not know where to move them.

Thoughts on the above would be appreciated. No pictures yet as they would just be of an empty lot. A sketchup drawing is in the works.

Questions that are currently eating at me are:

1) Are there any questions or requests to make of the builder that would help down the line? I have told them what I intend to do (and this is Nashville), but they are generally going to to do what they do. Are there certain things that I should be really on the lookout for?

2) Are there any thoughts/recommendations concerning a split (not mini) HVAC systems and mechanical room in a basement in proximity to a studio. Are they any ideas on mitigating the noise? When it was first mentioned, my first thought was “oh ****” how am I going to deal with this. Reassurance (or tellingg me I am SOL) would be helpful as I do not know what, if any, problems this will entail.

3) Since I will likely have to work around one or more joist supports, I am wondering how this is typically handled. I mean more in the acoustics sense. Where ever they end up, the drum kit will obviously have to find a different location. If the studio space can be designed where the posts run inside a wall, say between the live and control room, is that good or bad? Do they just need a big box of wallboard around them stuffed with 703? What is the typical solution? I have not found anything concerning this (probably need better search terms).

4) We have the option to get either the standard 200 amp electrical service or, at a cost, 400 amp service. I have asked for but have not seen a load calculation yet. As a rule of thumb, does having extra capacity help in any way. Voltage sag is always an annoyance from appliances kicking on and I am somewhat sensitive to that in general. Does it help with line noise levels as all?

5) The exterior walls will be either poured concrete of typical exterior stick and frame construction. I do not know how high the concrete will go. In some sections where the exterior side is dirt it should extend up to the main floor, while in others it may only be a few feet. The house is on a hillside with the front side in the dirt so to speak. There actual exterior (where not dirt) will have house sheathing, the standard air gap, and then bricks attached to the sheathing in the typical manner with metal ties. Two issues have popped into my head. Both concern the design of the MAM walls. First, I believe that I read somewhere (but can’t now find) on the site that because the bricks are tied to the sheathing, the sheathing and bricks are taken together as a single leaf. Is this the case? I remember there being some differing opinions on the issue. Second, what, if any design concerns, should I be looking at for sections where the basement exterior walls are concrete down low and stick and frame the rest of the way up?

Apologies for such a long initial post. It has taken a bit to pull together my initial thoughts. I will have many more. Thanks for any feedback. Let me know if you need more information (I think that I have followed the forum rules). I have already learned quite a bit having lurked here for over a year.

Best.

Point 2 above edited to indicate larger available space.

When they are building it, try to get as much ceiling height as possible!!!! Almost anything else can be changed later.

Eric Best wrote:When they are building it, try to get as much ceiling height as possible!!!! Almost anything else can be changed later.

Still in the design and permitting phase. I have asked for as much height as possible to everyone I speak to. Was told by the architect that there minimum unfinished floor to bottom of the joist is 11ft for a basement. This may simply be a codes thing. The lot has a steep drop off. Terrain and slope factors. They are working on the basement plan at the moment.

The reply I keep hearing is "The typical ceiling height in our basements are 11’ from slab to bottom of i-joist." So, they are not committing to anything more than that and I am assuming that this is a codes thing or a minimum construction standard. Any thoughts from someone familiar with Tennessee codes or a link to a codes reference would be appreciated.

I am not holding my breath but the topology may help push it a bit higher. The guy next door has a crawlspace that I thought that I measured as 14' from gravel to the bottom of the I-joist. I cannot find any note that I may have made and may not be remembering correctly. I am not sure that I can get back to measure it again. Topology is, of course, different from lot to lot (middle Tennessee has quite hilly and varied terrain), though with my eye it look to have a similar distance from where the back of the house would sit to the street level. Also, I am unfamiliar with the details of basement slab construction in terms of how much is dug out versus how much is built up from the graded footprint.

Given typical engineered I-joist construction for the floor above, what is a typical maximum floor to ceiling height in the finished space with an 11' slab to joist distance?

Any thoughts on dealing with joist support columns would be appreciated as well.

Thanks much.

Working on scheduling a meeting to go over the "basement plan" next week. Also working on as sketchup of the available space. Ran into some how to use it issues and some measurements that did not add up. Reading through Rod's book in between managing small children. Not sure if it is great bedtime reading for them, but getting 'em started on the right track early works for me .

Any feedback on any of the above would be appreciated greatly.

Thanks.

OK. Got the basement plan. Pulled it into Sketchup and drew in the basic features more or less to scale.

The 23' x 40' 10" space is only a general idea of the area I have to work with. The various pushouts are usable (e.g., the 3' x 15' pushout on the right hand wall) and the dimensions are only a first cut at where the inner leaf would be plus or minus a few inches. The intention is to put a control room, a live room, and an iso/vocal booth in the space.

The what look like "X's" are actually rectangles indicating the support column placement as indicated on the drawing. The actual placement is approximate and I assume that they will actually be steel posts. The largest footprint without any posts is in the upper right corner and is approximately 16' x 16'. I would, of course not build a square room!

The obvious question is how to work around them. I do not know yet if any can be moved or removed and a larger support beam used. That is the subject of a meeting next week with the builder.

Any thoughts would be appreciated.

Thanks.

Met with the architect today. May be able to remove one column - the one middle one below the word "column" in the diagram. That would open up the central space some. He will be getting back to me.

Could use some advice on how to deal with columns that cannot be moved. Is it best to place them inside walls or is it possible to simply enclose them in drywall if in the center of the room?
What are the acoustic ramifications?

Thanks.

Have an additional question.

The builder has provided a quote for removal of the post that is reasonable. The trade off is that the beam that the remaining two posts support will be 6 inches thicker (i.e., lower into the basement). They also provided a reasonable quote for moving the beams up into the joists and using hangers from beam to beam instead of the joints sitting on top of the beams and running the width of the basement. This should, in principle, allow me to have a higher ceiling (even accounting for the 6" thicker beam) in the space I currently envision the control room.

The "catch" to this arrangement is that the HVAC ducting now has to drop down to go under the beams where it needs to instead of being completely above the beams and through the joists. At least one will most likely be routed under the beam of the control room meaning that moving the beams up may not actually buy me anything because I still have to drop the ceiling down in that location to account for the duct. I may or may not be able to zig/zag the ducts around the end of the beam through the joist. At this point, I have no way of knowing without discussing with the hvac guy. It most likely will not be an 18" trunk line but it could be.

The question is it generally a good or bad idea to move the beams up into the joists?

Any thoughts on this wrinkle.

I would have additional images from sketchup but it has decided to drive me crazy this late at night.

Thanks.

Below is a picture of my current planned layout. The overall idea was to find the largest open space for the control room. With the middle post removed (and the beam made thicker), that space is the middle area, as noted. The upper area would be for a live/rehearsal space. The lower space could be used for an isolation area. None of the space usage is written in stone.

The dimensions shown are approximate and show the space available, minus the posts. Though there is space between the areas, wall dimensions are not accurately accounted for. The built rooms would conform to one of the recognized ratios and certainly would not be square. The Control Room is not drawn as a rectangle simply to show the space available not it indicate that the room would be built with this particular shape.

The ceiling height is supposed to be a minimum of 10'.

Now to the interesting part.

The beam (the darker one) that cuts through the center of the proposed control room is ~16" thick (top to bottom). This is 4" thicker than the others to account for the larger span with a post removed. The beam sizing, etc. was done by the builder. Joists are standard engineered I-joists and run horizontally. I then have three choices, it seems:

1) Leave the beam under the joists and base the ceiling height on the bottom of the beam 16" below the joists. This gives the lowest ceiling height but the ceiling is flat.
2) Leave the beam under the joists and base the ceiling height on the bottom of the joists and then box around the beam. This gives a 16" higher ceiling over most of the space. But, there is now a large reflective surface on the ceiling to deal with.
3) Move the beam into the joists using joist hangers and gain 12"-16" over the entire ceiling. This should give the highest overall ceiling with the caveat that now things that would otherwise go over the beam now have to go under it.

In case 1) and 2) some, but possibly not all, plumbing and hvac ducting could be run between the joists above the beam. It is not known but is still possible that either plumbing or hvac ducts would still need to go under the beam.

In case 3) ALL hvac and plumbing would have to either go under or be routed around the beam. NONE can go through it, of course.

After several discussions with the builder, my thinking is to go with 3), moving this beam into the joists. There are three things driving this decision. First, I will have an opportunity to meet with the plumber and hvac guy to discuss routing the ducts and pipes (there are bathroom drains that are on the right side of the beam). Second, even if a 4" to 8" soffit box needs to be built; that is better than a 16" one, and it is possible that one would be needed under the beam anyways. If that becomes the case, the only issue is symmetry in the room if a soffit is needed only on one side. Third, ducts and plumbing can be redone if needed much more easily and cheaply than moving a beam after the fact.


Am I missing something?
Any comments on the proposed space usage?
Does raising the beam look like it will cause more headaches than it solves?
Is there any other organization of the space that would make more sense?

Thanks.

I'm not sure if you've seen Mike's build thread, here:

http://www.johnlsayers.com/phpBB2/viewt ... =2&t=19949

He just went through a very similar situation, and came up with an excellent solution. I'm not sure if that is applicable in your case (I'd need to see photos of the actual beams, joists, ducts, etc in your room), but it might give you some ideas.

In the meantime, a few comments about your thread:

... quiet solo jazz guitar and ukulele to dimed amps and full 4 piece rock groups. Simple guess is 40 or 50 dB to 100+ for recording/practice

I think your guesses are a bit on the low side! 40 dB is what most people would consider practically silent. That's about as loud as a soft whisper. 100 dB would be very quiet for drums: I commonly measure them fifty to a hundred times louder than that, at around 115 to 120 dBC.

Budget is sufficient to build out this space.

I like that kind of budget! That's excellent, as small budgets often impose limits on what can be done, whereas large budgets allow for a lot more options.

Later this year, family and all will be moving into a house that is being built.

If it is not yet built, then you can solve all of your issues right now! Just build it different!

I guess I misunderstood your situation: I thought you were dealing with an existing basement, but now it seems that the only thing that exists is plans on paper?

The basement floor to the bottoms of the joists above is supposed to be at least 11 ft. I am guessing that I can get 9 to 10 foot ceilings in the built out space;

If you do everything right, and budget is not a problem, then you could potentially end up with your ceilings as high as 10' 9".

The floor above will be (basement upwards) joists with pink insulation between them, a subfloor of some sort and then ...

Do yourself a huge favor, and specify that the subfloor will be two layers of thick, dense "some sort". Eg, two layers of 3/4" OSB, MDF, plywood, etc. Joints staggered between layers, Green Glue between layers. This will require some re-design of the house in places, as the sub-floor will be twice as thick as usual, but that's a small price to pay for the immense benefits of having that extra mass and damping up there.

5) In the basement there is to be a mechanical room to house the furnace, evaporator, and air handler for a split HVAC for the main floor with space for an additional one for the basement, including the studio. The location and size is to be determined.

Excellent! That also means you get to determine where the ducts will run, what sizes they will be, how quiet the furnace and HVAC system will be, etc. You can keep all the ducts away from your studio area, and only route them through places that do not affect you. You also get to size the system so it can cover your studio needs as well. You are in a very fortunate position here: an un-built house with a good budget where you egt to control many, many parameters that most studio builders do not have any control over.

6) The duct work from the mechanical room to the main floor vents will be the flexible kind (I believe).

Some of it will likely be flexduct, but some will also very probably be metal duct.

Size and where it will be run are unknown;

That's the beauty of your situation! YOU can decide where it will be run, and what sizes it will be! It is just lines on paper right now, so you can move those lines at relatively little expense. Moving real ducts is a LOT more expensive...

There is intended to be a separate electrical subpanel only for the studio;

Excellent! specify "star grounding" for all of your studio electrical system. Important.

9) There will be a number of steel posts to support the span of the joists

Some or all of those can be eliminated or moved to more convenient places. Since this is all just lines on paper, you can change all of that by changing the specs. Switch to RSJs, for example (as Mike did) will allow you so span much larger distances in a much thinner profile than wood or engineered joists. It adds cost, yes, but you said that budget is not a problem.

a) there may be additional cost involved to beef up joists, etc.

Right. That goes without saying.

and b) since I have not sited the studio in the basement yet, I would not know where to move them.

Two options here: 1) Eliminate them completely by extensive use of RSJs and engineered joists, and/or 2) design the studio carefully FIRST, and only when that has been done, THEN decide where you can put the support posts.

No pictures yet as they would just be of an empty lot.

2) Are there any thoughts/recommendations concerning a split (not mini) HVAC systems and mechanical room in a basement in proximity to a studio. Are they any ideas on mitigating the noise? When it was first mentioned, my first thought was “oh ****” how am I going to deal with this. Reassurance (or tellingg me I am SOL) would be helpful as I do not know what, if any, problems this will entail.

If you choose your equipment correctly, and get it installed properly. using vibration mounts, isolation sleeves, silencers, etc, then it should not be a problem.

3) Since I will likely have to work around one or more joist supports, I am wondering how this is typically handled.

When there is no choice, I try to design the studio around the support columns, and keep them inside the MSM wall cavities, where they will not be an issue.

If the studio space can be designed where the posts run inside a wall, say between the live and control room, is that good or bad?

Good!

Do they just need a big box of wallboard around them stuffed with 703?

Probably not, although I have done that in extreme cases, with hollow steel posts that are resonant already.

4) We have the option to get either the standard 200 amp electrical service or, at a cost, 400 amp service.

Just for the studio, or for the entire house? if that's just for the studio, then 200 is more than enough. If its for the entire house, then you might need 400, depending on what heavy appliances and other large loads you will be using simultaneously.

As a rule of thumb, does having extra capacity help in any way.

Yep! It prevents the breakers form tripping if you draw too much current...

Voltage sag is always an annoyance from appliances kicking on and I am somewhat sensitive to that in general.

That's more to do with the actual wring than it is to do with the total capacity. Some electricians and contractors try to save money by using the thinnest conductor that is allowed by code, but that's a mistake: even though it can safely carry the load, the resistance is higher so the voltage drop is greater. Better to use over-sized conductors than undersized. Less chance of electrical fires too. More expensive, yes, but no sagging, flickering, overheating cables, etc.

Does it help with line noise levels as all?

No, but star grounding can help, if done properly. Assuming that your actual audio cabling is also done correctly, of course, and that all your gear is in good shape, electrically.

that because the bricks are tied to the sheathing, the sheathing and bricks are taken together as a single leaf.

Its a "coupled two-leaf system". It acts mostly like a single leaf, but also a bit like a two leaf in some aspects, especially in the sense that it does have MSM resonance which can detract from low frequency isolation.

Second, what, if any design concerns, should I be looking at for sections where the basement exterior walls are concrete down low and stick and frame the rest of the way up?

Specify that the external sheathing for the framed part is thick and dense. Eg, two layers of 5/8" or even 3/4" structural plywood or OSB, and make sure that it is all very well sealed, and there are no penetrations (water pipes, electrical, HVAC, vents, etc.) Joints to be staggered between layers, and Green Glue between layers.

Given typical engineered I-joist construction for the floor above, what is a typical maximum floor to ceiling height in the finished space with an 11' slab to joist distance?

If all the stars align, and the wind blows in the right direction, and you design and built perfectly, you could end up with a ceiling height of as much as 10' 9" or so, give or take a bit. You'd need to do lots of unusual stuff to make that happen, but it is totally feasible, and does not increase costs too much.

The 23' x 40' 10" space is only a general idea of the area I have to work with. The various pushouts are usable (e.g., the 3' x 15' pushout on the right hand wall) and the dimensions are only a first cut at where the inner leaf would be plus or minus a few inches. The intention is to put a control room, a live room, and an iso/vocal booth in the space.

920 square feet, with eleven foot ceilings? You are one lucky, lucky, LUCKY guy! Most home studio builders only dream of such a space. I have designed three-room studios in much smaller spaces (I even got a four room studio into 400 ft2 once... tiny, but functional!) So with that much space, you can really have a professional class studio, without any problem. I would take the time to design it very carefully, in all aspects, since it would be a real shame to waste that beautiful space... Your place can be way better than a typical home studio, and well up the scale alongside pro studios.

The what look like "X's" are actually rectangles indicating the support column placement as indicated on the drawing.

I cant be sure without seeing the complete plan, but I get the impression that all of those can be eliminated by using RSJs. Or maybe most of them.

In case 3) ALL hvac and plumbing would have to either go under or be routed around the beam. NONE can go through it, of course.

Not necessarily.... depends on the beam, then load, etc. A good structural engineer should be able to work with you to allow at least the plumbing and electrical stuff to go through the beam if necessary.

If that is absolutely out of the question, then re-route that stuff so it does not need to cross above the studio ceiling at all: send it around the ends of the studio.

And if THAT isn't possible either, then make the locations where the plumbing, electrical and HVAC stuff has to cross under the beam, to be inside the wall cavities, and soffited in. It means your wall cavities will have to be larger, but you have plenty of space there, so that's not an issue. And larger wall cavities are better anyway: More isolation, down to lower frequencies.

After several discussions with the builder, my thinking is to go with 3), moving this beam into the joists.

It sounds like the best option to me, but I don't have the plans in front of me, so I can't really say!

Third, ducts and plumbing can be redone if needed much more easily and cheaply than moving a beam after the fact.

Yup!!!


- Stuart -

Thanks Stuart very much for the reply.
I have interspersed comments here and will summarize everything with some further questions in a following post.

Soundman2020 wrote:I'm not sure if you've seen Mike's build thread, here:

http://www.johnlsayers.com/phpBB2/viewt ... =2&t=19949

He just went through a very similar situation, and came up with an excellent solution. I'm not sure if that is applicable in your case (I'd need to see photos of the actual beams, joists, ducts, etc in your room), but it might give you some ideas.

I have actually read his thread a few times now. Great solution for him. Lots of good information. Loved the anti-gravity pics.

In the meantime, a few comments about your thread:

... quiet solo jazz guitar and ukulele to dimed amps and full 4 piece rock groups. Simple guess is 40 or 50 dB to 100+ for recording/practice

I think your guesses are a bit on the low side! 40 dB is what most people would consider practically silent. That's about as loud as a soft whisper. 100 dB would be very quiet for drums: I commonly measure them fifty to a hundred times louder than that, at around 115 to 120 dBC.

You are of course right. I should had specified 115-120 on the upper end. The low end was just that, a guess. I had never thought much about quiet side levels. Pulled out my "trusty" RS meter and just now measured 75 or so dBC a few inches from a lightly strummed ukulele and mid 60's at about a foot and a half. Always, happy to be corrected. I have more on levels below.

Budget is sufficient to build out this space.

I like that kind of budget! That's excellent, as small budgets often impose limits on what can be done, whereas large budgets allow for a lot more options.

Later this year, family and all will be moving into a house that is being built.

If it is not yet built, then you can solve all of your issues right now! Just build it different!

I guess I misunderstood your situation: I thought you were dealing with an existing basement, but now it seems that the only thing that exists is plans on paper?

Yes (and no). The basement does not quite exist just yet. We are, however, beyond the plans on paper stage. Permits have been pulled, framing ordered, and dirt has begun to be moved around. The builder has been otherwise good about modifying things to my advantage acoustically, or at least patient while listening to me go on about it. I was able to get some good things but not all.

The basement floor to the bottoms of the joists above is supposed to be at least 11 ft. I am guessing that I can get 9 to 10 foot ceilings in the built out space;

If you do everything right, and budget is not a problem, then you could potentially end up with your ceilings as high as 10' 9".

The floor above will be (basement upwards) joists with pink insulation between them, a subfloor of some sort and then ...

Do yourself a huge favor, and specify that the subfloor will be two layers of thick, dense "some sort". Eg, two layers of 3/4" OSB, MDF, plywood, etc. Joints staggered between layers, Green Glue between layers. This will require some re-design of the house in places, as the sub-floor will be twice as thick as usual, but that's a small price to pay for the immense benefits of having that extra mass and damping up there.

Not wanting to count my ceiling height before it is built, but 10’9” sounds pretty good.
I did ask about doubling the subfloor. Great idea! It was, however, too late in the process for a change of that nature. I did learn that the subfloor is 3/4" OBS. I will have to look into doing what Mike did, beefing it up from below, assuming no structural issues.

5) In the basement there is to be a mechanical room to house the furnace, evaporator, and air handler for a split HVAC for the main floor with space for an additional one for the basement, including the studio. The location and size is to be determined.

Excellent! That also means you get to determine where the ducts will run, what sizes they will be, how quiet the furnace and HVAC system will be, etc. You can keep all the ducts away from your studio area, and only route them through places that do not affect you. You also get to size the system so it can cover your studio needs as well. You are in a very fortunate position here: an un-built house with a good budget where you egt to control many, many parameters that most studio builders do not have any control over.

6) The duct work from the mechanical room to the main floor vents will be the flexible kind (I believe).

Some of it will likely be flexduct, but some will also very probably be metal duct.

Size and where it will be run are unknown;

That's the beauty of your situation! YOU can decide where it will be run, and what sizes it will be! It is just lines on paper right now, so you can move those lines at relatively little expense. Moving real ducts is a LOT more expensive...

Yes, I think that I am in a pretty good spot at the moment with respect to HVAC. I have a lot of work to do though and will likely have additional questions. (See the next post for a couple I have now.) The mechanical room is being built with acoustic isolation from both the main living space and the studio space in mind. I also specified that the external condensers are to be placed on the side of the house opposite the studio. There is an "if possible" clause in there, so we will see. They would normally be on the same side. I would like to learn more about how to quiet the blasted things still. (See question below)

There is intended to be a separate electrical subpanel only for the studio;

Excellent! specify "star grounding" for all of your studio electrical system. Important.

9) There will be a number of steel posts to support the span of the joists

Some or all of those can be eliminated or moved to more convenient places. Since this is all just lines on paper, you can change all of that by changing the specs. Switch to RSJs, for example (as Mike did) will allow you so span much larger distances in a much thinner profile than wood or engineered joists. It adds cost, yes, but you said that budget is not a problem.

a) there may be additional cost involved to beef up joists, etc.

Right. That goes without saying.

and b) since I have not sited the studio in the basement yet, I would not know where to move them.

Two options here: 1) Eliminate them completely by extensive use of RSJs and engineered joists, and/or 2) design the studio carefully FIRST, and only when that has been done, THEN decide where you can put the support posts.

Unfortunately, timing is everything. A full design of the studio is not possible with the build (and my work) schedule. I did remove what seemed to be the most offending post with the beam being a thicker engineered wood - not steel - one. The cost was quite reasonable, actually. I also had it moved up into the joists. The other beams not in the space were left below the joists. There was a lot of back and forth with the builder over this. It is probably not the optimal option but should be an improvement viz the studio in any case.

No pictures yet as they would just be of an empty lot.

2) Are there any thoughts/recommendations concerning a split (not mini) HVAC systems and mechanical room in a basement in proximity to a studio. Are they any ideas on mitigating the noise? When it was first mentioned, my first thought was “oh ****” how am I going to deal with this. Reassurance (or tellingg me I am SOL) would be helpful as I do not know what, if any, problems this will entail.

If you choose your equipment correctly, and get it installed properly. using vibration mounts, isolation sleeves, silencers, etc, then it should not be a problem.

Good to hear. See further questions below about HVAC.

3) Since I will likely have to work around one or more joist supports, I am wondering how this is typically handled.

When there is no choice, I try to design the studio around the support columns, and keep them inside the MSM wall cavities, where they will not be an issue.

If the studio space can be designed where the posts run inside a wall, say between the live and control room, is that good or bad?

Good!

Do they just need a big box of wallboard around them stuffed with 703?

Probably not, although I have done that in extreme cases, with hollow steel posts that are resonant already.

I think that removing the one post solves this for the most part. Of course, if the layout is different than what I proposed above I may have problems.

4) We have the option to get either the standard 200 amp electrical service or, at a cost, 400 amp service.

Just for the studio, or for the entire house? if that's just for the studio, then 200 is more than enough. If its for the entire house, then you might need 400, depending on what heavy appliances and other large loads you will be using simultaneously.

As a rule of thumb, does having extra capacity help in any way.

Yep! It prevents the breakers form tripping if you draw too much current...

Voltage sag is always an annoyance from appliances kicking on and I am somewhat sensitive to that in general.

That's more to do with the actual wring than it is to do with the total capacity. Some electricians and contractors try to save money by using the thinnest conductor that is allowed by code, but that's a mistake: even though it can safely carry the load, the resistance is higher so the voltage drop is greater. Better to use over-sized conductors than undersized. Less chance of electrical fires too. More expensive, yes, but no sagging, flickering, overheating cables, etc.

Does it help with line noise levels as all?

No, but star grounding can help, if done properly. Assuming that your actual audio cabling is also done correctly, of course, and that all your gear is in good shape, electrically.

For the whole house. Plan to go with the 400 service and will discuss wire sizes and star grounding with the electrician. There is already a note to meet with him concerning the wiring of the room I will be in before the studio is built.

that because the bricks are tied to the sheathing, the sheathing and bricks are taken together as a single leaf.

Its a "coupled two-leaf system". It acts mostly like a single leaf, but also a bit like a two leaf in some aspects, especially in the sense that it does have MSM resonance which can detract from low frequency isolation.

Makes sense. Understood.

Second, what, if any design concerns, should I be looking at for sections where the basement exterior walls are concrete down low and stick and frame the rest of the way up?

Specify that the external sheathing for the framed part is thick and dense. Eg, two layers of 5/8" or even 3/4" structural plywood or OSB, and make sure that it is all very well sealed, and there are no penetrations (water pipes, electrical, HVAC, vents, etc.) Joints to be staggered between layers, and Green Glue between layers.

Extra layers on the outside not possible at this stage. There is a single external hose bib on the studio side of the house. So, I will have to deal with that. There should be no other penetrations.

Given typical engineered I-joist construction for the floor above, what is a typical maximum floor to ceiling height in the finished space with an 11' slab to joist distance?

If all the stars align, and the wind blows in the right direction, and you design and built perfectly, you could end up with a ceiling height of as much as 10' 9" or so, give or take a bit. You'd need to do lots of unusual stuff to make that happen, but it is totally feasible, and does not increase costs too much.

The 23' x 40' 10" space is only a general idea of the area I have to work with. The various pushouts are usable (e.g., the 3' x 15' pushout on the right hand wall) and the dimensions are only a first cut at where the inner leaf would be plus or minus a few inches. The intention is to put a control room, a live room, and an iso/vocal booth in the space.

920 square feet, with eleven foot ceilings? You are one lucky, lucky, LUCKY guy! Most home studio builders only dream of such a space. I have designed three-room studios in much smaller spaces (I even got a four room studio into 400 ft2 once... tiny, but functional!) So with that much space, you can really have a professional class studio, without any problem. I would take the time to design it very carefully, in all aspects, since it would be a real shame to waste that beautiful space... Your place can be way better than a typical home studio, and well up the scale alongside pro studios.

This is great to hear from you! Hopefully, I have not already screwed too much up. Would have liked to have gotten the beefier walls and floor above. But, those stars did not align.

The what look like "X's" are actually rectangles indicating the support column placement as indicated on the drawing.

I cant be sure without seeing the complete plan, but I get the impression that all of those can be eliminated by using RSJs. Or maybe most of them.

In case 3) ALL hvac and plumbing would have to either go under or be routed around the beam. NONE can go through it, of course.

Not necessarily.... depends on the beam, then load, etc. A good structural engineer should be able to work with you to allow at least the plumbing and electrical stuff to go through the beam if necessary.

If that is absolutely out of the question, then re-route that stuff so it does not need to cross above the studio ceiling at all: send it around the ends of the studio.

And if THAT isn't possible either, then make the locations where the plumbing, electrical and HVAC stuff has to cross under the beam, to be inside the wall cavities, and soffited in. It means your wall cavities will have to be larger, but you have plenty of space there, so that's not an issue. And larger wall cavities are better anyway: More isolation, down to lower frequencies.

I am told that they cannot put any holes in this beam. I plan to have everything routed to minimize any unnecessary intrusions into the control room space at least. On balance, my estimation is that by moving the one beam into the joists I will gain overall even if something has to be routed under it and soffit built to enclose it.

After several discussions with the builder, my thinking is to go with 3), moving this beam into the joists.

It sounds like the best option to me, but I don't have the plans in front of me, so I can't really say!

Third, ducts and plumbing can be redone if needed much more easily and cheaply than moving a beam after the fact.

Yup!!!


- Stuart -

Thanks for the input Stuart. It is helpful. My next post will have some follow-up questions.

In summary, so far I have the following:

Just finished Rod’s book and starting the Acoustics Handbook (made it to page 2 before I had to play I-spy ).

Approximately 920 sq ft of basement space on a concrete slab.

Approximately 10.5+ foot ceilings.

Walls of a combination of poured concrete and stick and frame with a standard brick exterior. Sections where there is concrete will be backfilled some with dirt. How much backfill is yet to be seen.

Rooms above include a bedroom, full bath, and closets.

Flooring above consists of engineered joists supporting 3/4” AvanTech tongue and groove subfloor and carpet with pad on top of that except for bathroom area where it is tile.

One beam that cuts across the area contemplated for the control room was moved into the joists to, on balance, give more ceiling height across a larger area instead of requiring a large (16”) soffit around it. I saw this as a big, unknown reflective surface across the middle of the space that could be reduced/eliminated this way. The tradeoff is that routing of plumbing and HVAC is possibly more complicated. Trouble will likely be in providing air to the bedroom and bath.

A couple of posts remain in the space. I initially saw the total space breaking into three areas: live room, control room, and iso room. Hopefully, my initial layout ends up being reasonable though I realize there may be a more optimal solution. One “issue” I see with it is with the control room layout and windows/sight lines to the other rooms. With the control room oriented the long way, windows are on the sides possibly in first reflection locations and viewing from the desk is not easy. Please chime in if a better alternative is seen.

Though Stuart’s recommendation for heavier, layered subfloors above and sheathing on the side was a great one, framing, subflooring, etc. was already being ordered. I will have to address adding mass using the methods similar to what Mike did in his build in the thread referenced above.
The mechanical room housing air handlers and furnaces for the main floor and the basement will be enclosed according to code. The idea is to build it with a decoupled, two leaf wall and ceiling. The condensers are specified to be placed on the opposite side of the house from the studio – outside, of course.
Planning of the routing of HVAC and plumbing is on the to do list.

Concerning sound levels, Stuart is correct that my initial numbers were a bit off the mark. For recording/practice, the levels would run from say the low 60’s to 120, with average loud being ~100 and normal levels 80-90. Above the studio is a bedroom, for which nighttime would need to be in the 40 range, which likely means no band practice or cranked amps at midnight when my wife is trying to sleep in any case.

The location is in a fairly quiet residential area. More countryside than city. Outside levels are in the 40-50 level from crickets, frogs, distant trains, and cars at night with peaks in the 70 range from planes overhead. Daytime levels could range from 50 to 85, though I don’t have a good handle on that yet. Max levels would come from planes on approach and lawnmowers. I have no idea what the noise level of kids running around on the floor above would be like but do know that the thump-thump of little feet can carry quite well through a structure. The local ordinance seems to be not a dB level but a “don’t let it bother anybody” level so that puts me at a 40-50 dB level at the property line I suppose.

Based on the above max and min the desired dB isolation would be around 80 dB (120 – 40), which is a fairly big number. Most often a 70-75 dB isolation level would be the max necessary. A design that could target 80 would likely achieve what I need. Is this even possible or am I dreaming too much?

Current questions beyond any thoughts on the above:

1) HVAC in mechanical room. Are there any products that work for additional noise control? Stuart mentions vibration mounts, isolation sleeves, silencers. I am familiar with silencers from reading threads here and from Rod’s book. I am interested in vibration mounts/pads. Any recommendations? I am not familiar with “isolation sleeves.” What are they?

2) HVAC condenser/compressor outside. Are there any recommendations on quieting these beasts in general. I ran across an HVAC discussion site where someone asked about plastic vs concrete pads for siting these (http://hvac-talk.com/vbb/showthread.php ... stic-thing). It was noted that many people use them for noise control. How successful they are was not actually stated. Has anyone used these or other ideas successfully?

3) Is 80dB isolation possible as a design target for a home studio given what I have to start with?

4) I have a RadioShack dB meter. I believe that I got it to use with RPlusD. Is there a better recommendation?

Thanks again.

1) HVAC in mechanical room. Are there any products that work for additional noise control? Stuart mentions vibration mounts, isolation sleeves, silencers. I am familiar with silencers from reading threads here and from Rod’s book. I am interested in vibration mounts/pads. Any recommendations? I am not familiar with “isolation sleeves.” What are they?

Isolation sleeves are usually canvas or something similar, and made very much like the sleeve on your shirt, or a trouser leg: a floppy, flexible cloth cylinder, but air-tight. They are used to join two "things" that need to have air flowing between them, but that cannot be allowed to touch each other mechanically. For example, they are often used to connect the AHU to the ducts: The AHU is noisy, vibrates, rattles, etc, and you do not want to transmit that into the ducts, so you use a canvas sleeve to decouple the duct form the AHU.

2) HVAC condenser/compressor outside. Are there any recommendations on quieting these beasts in general.

Put them on isolation mounts, and choose one that is very silent in the first place.

3) Is 80dB isolation possible as a design target for a home studio given what I have to start with?

It is possible, yes, but you'd need to add several zeros to your budget. Anything over about 60 is already getting into the realm of "Really Hard To Do". Over 70 is "Man This Is Incredibly TOUGH". Over 80 is "How Many Million Dollars Do You Want To Spend?"...

4) I have a RadioShack dB meter. I believe that I got it to use with RPlusD. Is there a better recommendation?

That should be fine, but if you want something better then look for an Extech or Galaxy on eBay, or Amazon. Should be around US$ 100 or so, maybe a bit more.

- Stuart -