[Mike-48]

Based on your feedback, and after thinking it over and talking with an acoustician, I'm going ahead with my basement room.

The next question is the floor. Jim Smith in his book Get Better Sound recommends covering a concrete floor with wood by laying sleepers and putting subflooring on top. I like the idea, but in my room, this could reduce the height further. (It will be slightly less than 7 feet (2.1 m) already.)

What is a good choice for flooring in a basement listing room? We don't have moisture collecting in the basement, but we DO live in Oregon, so there is some humidity. Also, cost is a consideration: a hardwood floor in the entire room may be too expensive. I was considering wood for 2' around the edges and a low-pile carpet in most of the room (if that's practical).

Maybe I should talk to a flooring contractor -- but I hope for more acoustically oriented advice first.

All comments appreciated!

[cheap-Jack]

Hi.

.

What is a good choice for flooring in a basement listing room?
 I was considering.. a low-pile carpet in most of the room (if that's practical).
All comments appreciated!

That's what I have done in flooring my basement audio den:-

Objective:  acoutically passive, money saving, easy keeping, zip footdrop noise.

I had the entire concrete basement floor installed wall-wall-carpet with thick rubber underlay. Low low profile synethic wool surface.

A large med to high profile wool carpet laid between the loudspeakers & the sweet spot.

So far so good.

c-J

[Big Red Machine]

Mike, this is what I did to my entire basement floor to save valuable height but give me a cushion, small R insulating value, and easy attachment of stud walls with nails or screws w/o power nailing into concrete:

Owens corning pink fanfold insulation comes in 1/4" thick x 48" x 50 feet folded in 2 foot sections.  On top of that 7/16" OSB held together at the sheet edges with roofing clips.








No gluing required.  The weight of the OSB and friction of the fanfold holds everything in place and you just build away on top of that.

[Mike-48]

Mike, this is what I did to my entire basement floor to save valuable height but give me a cushion, small R insulating value, and easy attachment of stud walls with nails or screws w/o power nailing into concrete:

Owens corning pink fanfold insulation comes in 1/4" thick x 48" x 50 feet folded in 2 foot sections.  On top of that 7/16" OSB held together at the sheet edges with roofing clips.

No gluing required.  The weight of the OSB and friction of the fanfold holds everything in place and you just build away on top of that.

Thanks!  Nailing into the slab is something I also want to avoid.  Your method is a great idea that goes onto the top of my list.

And what did you put on top of the OSB, if I may ask?

[Big Red Machine]

carpeting or wood flooring directly.  You can pad it and carpet it or lay down some tar paper for wood or laminate flooring.

Have you thought about splaying your walls?  Or going with hat channel and isolators, double drywall, and green glue?

[Mike-48]

Have you thought about splaying your walls?  Or going with hat channel and isolators, double drywall, and green glue?

The plan is hat channel, isolators, double drywall, and green glue for the walls; but to save height, a double layer of QuietRock fastened directly to the joists for the ceiling. I expect the QuietRock to be a bit less effective than channel, but it saves several inches of height.

The plan is for solid-core doors with full seals. There is an anteroom at the long end, so sound from the basement would have to travel through two doors to get into the listening room. We will be using flex duct for a portion of the HVAC close to the air handler to minimize sound transfer, and I plan to put the HVAC vents into the walls to protect the acoustic integrity of the ceiling. For the same reason, all lighting will be from lamps plugged into wall sockets.

I'm not planning to splay the walls -- the space available doesn't allow it easily, and from what I understand, it's an inexact science. I do plan to use extensive acoustic treatments, both absorption and diffusion.

Did you use non-parallel walls in your project?

[Big Red Machine]

No.  But I wish I had.  Next time I will go to all the extremes, even adding isolation matting.

[django11]

For the floor Dricore or something like it is diy friendly and prudent if you have humidity worries.    http://www.dricore.com/en/eIndex.aspx

I would use (and did use) resilient channel for the ceiling.  It only take 3/4 inches and is quite effective

[Mike-48]

No.  But I wish I had.  Next time I will go to all the extremes, even adding isolation matting.

Hmmm . . . . so the sound channel, etc., didn't provide sufficient isolation? 

I am working with an acoustician, but when I suggest any "belt and suspenders" approach, he is dubious.

[Mike-48]

For the floor Dricore or something like it is diy friendly and prudent if you have humidity worries.   

I would use (and did use) resilient channel for the ceiling.  It only take 3/4 inches and is quite effective

Thanks!  Dricore looks good.  Interesting about the channel. The clips & channel recommended to me seem to be thicker.

[richidoo]

Be sure to coat the raw concrete with Drylok before laying down anything else to prevent mold growing on the concrete and keep the humidity down. It kills that cold basement feeling and smell.

A friend has a concrete floor in his listening room with a resilient plastic layer then special strand board sheet, then pad and carpet. It is very comfy, and his room sounds great. He did a lot of research, so I can get the details if you want.

Rich (also in NC )

[Mike-48]

Be sure to coat the raw concrete with Drylok before laying down anything else to prevent mold growing on the concrete and keep the humidity down. It kills that cold basement feeling and smell.

A friend has a concrete floor in his listening room with a resilient plastic layer then special strand board sheet, then pad and carpet. It is very comfy, and his room sounds great. He did a lot of research, so I can get the details if you want.

Rich (also in NC )

Rich, Thanks!  --and thanks for the offer.  It would be great to get the details from you.  Either you can post here, or if this board uses PMs (I can't remember), you can send them that way.  I do keep a dehumidifier running in the basement, which helps a lot.

P.S. As my new avatar shows, we moved from beautiful Beaufort, NC, a while ago. We miss some things about it, and we love the extensive music scene in Portland. For example, Saturday we heard this drummer with a band at a house party -- http://tinyurl.com/d4rw25a -- and Sunday, it was a piano recital by Valentina Lisitsa. Tonight, jazz at a local restaurant.

[Big Red Machine]

Hmmm . . . . so the sound channel, etc., didn't provide sufficient isolation? 

I am working with an acoustician, but when I suggest any "belt and suspenders" approach, he is dubious.

No, the issue is standing waves/room modes and splaying would reduce this.

[Big Red Machine]

Thanks!  Dricore looks good.  Interesting about the channel. The clips & channel recommended to me seem to be thicker.

Dricore is expensive and probably over an inch on height.  The OC and OSB will chew up about 3/4".

[Mike-48]

Dricore is expensive and probably over an inch on height.  The OC and OSB will chew up about 3/4".

Well, at this point, I am trying to save every 1/4" in height that I can. I'll check all specs.

Modes and standing waves . . . perpetual problems in these rooms. Undoubtedly you have tried various bass traps. I found that separate subwoofers helped in my previous room. It took a lot of fiddling to get them positioned right, and the bass still had one suckout, but it was a lot better than before I added them.

[sturgus]

The cheap way is to just paint the floor and use area rugs. This way you won't loose any height. If you find that the sound is not to your liking then you can add a floor.
Sturgus

[richidoo]

Well, sorry to learn you left NC, but sounds like you found something better!

My friend emailed me back with the details:

Drylok on all concrete, walls and floors.
Delta-FL subfloor material, taped together with Tyvek tape.
Advantech 3/4" tongue-in-groove plywood
Pad and carpet

Subfloor and wood are floating, not attached to floor. The subfloor is about 1/4" thick, iirc...

Good luck Mike

[django11]

Delta-FL subfloor material, taped together with Tyvek tape.

What I like about this material is that it gives a thermal break and gives you an air gap that allows everything to breathe. Basement concrete floors come in many varieties from flat and bone dry to sweaty and wavy.  Build according to what you have...  and have fun!

[PDR]

I would use (and did use) resilient channel for the ceiling.  It only take 3/4 inches and is quite effective

Never seen hat track in isolated rubber mounts before....wow, been installing steel framing systems for 32 yrs.....thats a first. Do you know the rating it gives?

Regarding the resilient channel, been using that for a long time.....it gives a rating of down 10-11db, its esay and cheap, and is used for theatres....heres a 176 seat I have been working on. You can see the res bar in the photo.
Double 5/8"drywall, screwed to the res bar.

[django11]

Regarding the resilient channel, been using that for a long time.....it gives a rating of down 10-11db, its esay and cheap, and is used for theatres....heres a 176 seat I have been working on. You can see the res bar in the photo.
Double 5/8"drywall, screwed to the res bar.

The only thing to beware of when using the resilient channel is that you don't screw the drywall through the channel and into the stud.  That negates the whole purpose