Metal Buildings and Pole Buildings - Opinions?

[radiationroom]

It looks like I am going to be starting totally from scratch. Just got a quote on a metal building and it's made from 29GA steel which sounds a bit thin IMO.

I was also thinking about using pole construction for the exterior then building
"a building inside a building" for the interior.

I need at least 40dB of transmission loss if not more due to the neighborhood and the insurance company wants a "Class 1 - fire rated" roof due to being next to a wooded area with a history of fire.

Any suggestions on either or should I use standard stick construction on a block foundation?

Thanks in advance!

[JWL]

For the most part, mass is mass, although thin metal might have resonance issues of which I am ignorant.

If you can, calculate the mass of the metal walls, and compare it to traditional construction. The more mass you have (all else being equal), the more sound isolation you will have.

Remember mass is just one part of the equation, though. It has to be built correctly.

[jhbrandt]

It looks like I am going to be starting totally from scratch. Just got a quote on a metal building and it's made from 29GA steel which sounds a bit thin IMO.

That is definitely the way to go if you have the budget. What exactly are your requirements for this studio?

I was also thinking about using pole construction for the exterior then building
"a building inside a building" for the interior.

+1 We have done quite a few studios in this way.

I need at least 40dB of transmission loss if not more due to the neighborhood and the insurance company wants a "Class 1 - fire rated" roof due to being next to a wooded area with a history of fire.

That figure is probably a little light. How close are you to your nearest neighbor? AND What do you intend on recording? Rock drums CAN reach 120dB and if your local code requires no more than 50dB A-weighted at the curb, you will probably need a 70dB STL, especially at low frequencies. Being a new construction and 'on grade', you won't need a floating floor. So that saves a lot.

Any suggestions on either or should I use standard stick construction on a block foundation?

Thanks in advance!

We have done both. If you opt for the pole barn style be aware that you will need to frame out between the poles and add mass, as in Osb and a few sheets of gypsum board. This will contribute to the exterior partition. You will not be able to 'hang' a ceiling from the existing, most likely, and will need to set any isolated ceilings on top of the interior isolated partitions.
Alternatively, but more expensive, would be the standard stick construction with mass sheathing. In this type of build you would have the option of using spring hangers for the ceiling. - However, it is always preferred to have the isolated ceiling sit on top of the iso walls.

Cheers,
John

[Scodiddly]

29 gauge steel? Are you going to use the walls as plate reverbs?

[radiationroom]

The room will primary be used as a mix room with the occasional vocal tracking and to produce radio programming. I will be doing lots of commercial work and dance remix kind of stuff, so tracking full-on rock bands are not part of the plan. If I record loud acoustic drums in there it would be rare.

The building site is roughly 75 feet (US) from the neighbor's residence and roughly 100 feet off of the street. On property zoned residential but after discussing it with my local zoning board they don't care as long as there are no complaints and as long as the traffic turnover is at a minimum. It could be a glorified home theater as far as they are concerned.

Thanks for the replies!

[jhbrandt]

That is great news.. definitely doable there!

I would recommend a 'site noise survey' (you can do this yourself with an SPL meter). And get an average, general reading of the noise level outside vs. the same type reading inside the current building, as-is.

You need to identify exactly how much isolation you need in decibels. Then have a look at ir761 - link on my publications page - and find a wall configuration that will give you the needed attenuation.

Here is a simple test to determine the isolation needed:
------------------------
Noise Survey Test

Equipment required:
1) Digital SPL meter with peak hold function
2) package of 20 good quality balloons

Procedure:
a) inflate balloons tightly so that they are the same size.
b) set a reference level by adjusting the SPL meter to 'C' weighting and peak reading. note: popping a balloon can result in and SPL of 105-110 decibels
set the SPL meter on a stand ONE meter from the balloon and pop it. write down this peak reading. This is your reference.
c) set the SPL meter one meter away from the partition to be measured & pop a balloon on the other side of the partition. All doors and windows must be closed or measurements will be null & void. Measure where desired and write down the results.
d) a static measurement can be made either inside the quiet room to measure sound ingress or place the SPL meter outside while music is played to measure sound egress.
e) peak ambiant sound levels can be recorded by placing the SPL meter outside for a specified length of time.

Subtract the results of 'c' from the reference to see the partition STL.
------------------------

Then build that. --- You don't need to build a decoupled wall if you only need STC48... but you don't need to waste your money on a low STC wall if you need STC70 or more. Remember; the higher the STC number = the higher (exponentially) will the building cost be. Also not that when I use STC ratings, I use it for reference. You will be producing music which frequency response extends WAY below what STC will measure. The Low Frequency isolation will be most important.. and for the LF, you will need mass and lots of it.

Cheers,
John

[roscoenyc]

Lot of difference between a "pole barn" and a real engineered steel building like the kind available from Butler.

[roscoenyc]

Lot of difference between a "pole barn" and a real engineered steel building like the kind available from Butler.

[radiationroom]

Lot of difference between a "pole barn" and a real engineered steel building like the kind available from Butler.

Butler is just up the road from me. I will call them. Thanks!

[roscoenyc]

Lot of difference between a "pole barn" and a real engineered steel building like the kind available from Butler.

Butler is just up the road from me. I will call them. Thanks!

They have a range of building options from the spartan (agriculture) to the real top of the line.

[radiationroom]

I just talked with a mason who is looking for moonlight work who sez he can save the block walls of the building that I was planning to tear down by "stucco coating" the walls. His estimate is 1/3rd of the lowest "contractor estimate" I received. He has his own insurance and equipment.

My primary concern about this guy's offer is there is staircase cracking at several points that need fixed. He sez that coating the block will take care of that problem. Since I am not a mason his methodology is an open question to me.

If this mason can salvage my block walls at his price the equation changes totally. The block building is made with old-style "3 void" block which is much heavier than new "2 void" block. The interior is roughly 32 feet long by 18 feet wide by 8 feet high and the mason said there will be little problem in adding an additional two courses of block adding an additional foot to the ceiling height. Since I do not plan to subdivide my space that makes for a fantastic sized room.

What would you do? Save the block walls, re-roof and frame out the interior or start from scratch?

Thanks again for your advice!

[jhbrandt]

He has his own insurance and equipment.. that's a good start.

Unless the block and foundation is crumbling, it can be fixed. I don't really have enough information to comment intelligently.
Do some research and check with your local codes officer. They will tell you straight what is required (and safe) for certain structures.

Cheers,
John

[radiationroom]

Looks like my block building will be coming down. So it's back to either the metal building or stick-frame.

As a mental exercise..... What do you guys think about concrete board over gypsum under siding as exterior over wood studs?

For the walls I'm thinking studs ---> 5/8th plywood ---> green glue ---> 5/8th fire rated weather rated drywall (Densdeck?) ---> green glue ---> concrete board ---> wrap ---> vinyl siding?

For the roof I'm thinking 5/8th OSB ---> green glue ---> 5/8th fire rated weather rated drywall (Densdeck?) ---> GAF asphalt shingles?

Can't use OSB at ground level because I'm in a 100 year flood plane according to the local codes people.

[jhbrandt]

Heavy is good. You don't need GG.

MAM construction.. massive outer shell, air space, massive inner shell. Done. No worries.

Check local prices for the materials; Heavy/cheap = gooooood!
light/expensive = baaaad.

simple stuff really.

Cheers,
John