[bspaulding]

Greetings! This is my first post to this forum, and I am so stoked to have found the forum (hopefully) just in time as my basement remodeling project is underway, en route to becoming a multi-purpose family room / home theater. House is up on supports, the foundation has been ripped out, 5-foot deep trenches are dug around the location where the new foundation will be poured, and the rebar + forms are getting put in place as I type.


I have done a ton of online research, including reviewing many posts on this forum in order to learn as much as I can about how to properly build the main family room from a soundproofing perspective, as directly above the room are my daughters' bedrooms with the master bedroom not too far away above the garage that will be next to this room. I have depicted this in one of the attached diagrams of the upper floors. But I would love any/all input on other matters like lighting, HVAC, etc. I have attached a diagram that I will reference throughout this post. Many thanks in advance for whatever advice you can provide, confirmation (or refutation) of my assumptions, etc.

General Context

• House is in Burlingame, CA which is situated on the peninsula of the San Francisco Bay Area near the airport and built in 1925
• Split level, so new room being build underneath the upper part of the back of the existing house - which are all bedrooms, of course
• My primary goal is to keep sounds of TV, movies, video games, entertaining, etc. from waking up / disturbing anyone sleeping in rooms upstairs
• Weakest links seem to be windows and sliding glass patio door on Northeast wall. Also concerned with sufficient sealing and isolation to mitigate flanking into upstairs.

Here is how I plan to tackle the various aspects of the room, mainly focused on soundproofing...

Ceiling

• Double Drywall + Green Glue following guidance
  • Interleaved, caulked, backer rods with Double Drywall of walls at intersections per this post
  • Second layer installed perpendicularly to first
  • Acoustic caulk seams and intersections
• Hat Channels per specifications in this article and Sound Isolation Clips
  • Spacing: every 48" (will this be strong enough?) ***
    
  • Additional ones for supporting soffits
  • Are these RSIC-V's OK?
  • Use RSIC-1's (like these) that can attach to the side of the joists in order to minimize the amount of drop to ~1/4" and thereby maximizing ceiling height and reducing amount of excavation required
• R19 Insulation

Walls

• Double Drywall + Green Glue
  • Same techniques described above for ceiling
• Acoustic Caulk + Sill Gasket under bottom wall plates per bottom of this article and this post
• R13 Insulation
• Northwest + Northeast Walls
  • These will both be false walls
  • Based on some of the weaknesses I'm dealing with, are DC-04's or the like worth it? If not, any advice on how to support them?
• Southwest Wall
  • Am assuming the laundry room / bathroom provide an "air pocket" for upstairs. They are also beyond the sleeping areas above. Did not plan to DD + GG the walls or ceiling - cool?
  • Toward the South corner of the wall, it runs along the other side of the stairway to the upstairs living area. I assume that in this case consideration definitely needs to be given to either staggered stud wall or use of hat channel + clips - is one better / preferable to the other?
  • Also wondering about best way to secure the wall as it extends to the bathroom - I am more worried about how to isolate it from the ceiling - looks like RSIC-U's would work, but am again wondering if the door and window frames make this wasted effort
• Southeast Wall
  • Wall will be connected to the stem wall off the foundation
  • Plan to DD + GG one side of stud wall, but I was not going to do staggered studs or otherwise isolate - is that a problem? Believe the wall will attach to a beam, which brings up the question of using RSIC-U's or the like - or not
  • I should mention that the master bedroom is above the garage, and will not have a ceiling - just insulation at this point
  • Stairs up to door will be plywood framed platform - is there anything that would be necessary to do to keep sound from going through them into landing and hallway beyond? is this a concern or not?
  • Duct to Soffit - still working out how to get to the soffit on the Southeast wall. Currently, as shown in the light green on the diagram, we may figure out a way to go under the stairs into the wall at the other end, then up through in-wall metal duct to the soffit and out through the wall into the soffit - if we just stagger studded that little section of the wall, would it help or no?

Soffits / HVAC

• Plywood + Drywall + Green Glue (Example post)
• Depicted as purple entering crawl space at #6 and #8, while #4 is the more creative approach I previously described.
• Acoustic flex duct
• What kind of insulation?
• Any recommendations for sizing the soffit? Can I go really tight, or should there be a certain amount of room for insulation?
• Grills positioned in the middle on the side facing each other and blowing toward center of ceiling (#11 and #3)
• Use of appropriately sized PVC when traversing walls
• At #10 is where I plan to have all the home entertainment components. I will need to run conduit into the soffit and out into the crawl space in order to route Cat5, and such. I can probably route it directly into the built-in home entertainment shelves and cabinets that will be right there - and recommendations on soundproofing this, if at all?
• Similarly, I will also need to bring in speaker wiring through the wall - any special boxes, and techniques for minimizing leakage?
• Do I need to consider Dead vents (thread and specific comment)? Inline duct Silencers? Currently, the ducts aren't right-angling when they come out into the crawl space.
• Furnace will be in the #12 location

Floor

• Concrete slab
• Pergo with some tile near wet bar and in front of Patio door

Windows / Sliding Glass Patio Doors

• These seem to be the biggest weakness. I have read some posts that talk about potentially using neoprene to isolate the sliding patio door and windows from the structure; however, I am also concerned about the fact that the opening for the door and windows will connect the outside structure and inside floating wall. Any ideas?
• I am less concerned with noise reaching the neighbors as noise reaching occupants above

Interior Doors

• Solid Core for stairway as well as laundry room access points
• Automatically closing door bottoms (like these)
• Any other tips/tricks?

Lighting / Electrical

• Plan on using wall sconces all around the main room.
• With the windows and patio door issue, is stuff like using putty pads on outlet boxes worth the added expense and effort? Figured I would just concentrate on acoustical caulking of regular boxes

General

• Speaker isolation necessary? Currently, I plan to have a built-in entertainment center against the Northwest wall.
  • Would have the LCR speakers sitting on it
  • Subwoofer on the floor underneath it - do I need to try to isolate that from the Pergo floor?
  • Would wall-mounting the surrounds be ok, or defeat the purpose?

Again, thank you for whatever advice you can provide - may the Force be with you!

 

[BeerParty]

So, just to make sure I understand you correctly: the room will still have the windows and glass door after you have finished the room?


If that is the case, any attempt at soundproofing is probably useless. The issue is called 'flanking', and you can read about it at a bunch of different web sites. When talking about soundproofing a room, the analogy usually used is a fish aquarium. Think of the ceiling, walls, and floor of your room like the walls and floor of an aquarium, where sound is the water. Any gaps in the soundproofing (like your windows and doors) are like holes in the walls of the aquarium. No mater how thick the rest of the walls of the aquarium are, it will not hold water if there is a hole in the wall. Your windows and glass doors represent big holes.

 

[malovich]

I'm not a jedi master, maybe anakin when he was a slave where the general public may be a fetus in comparison but don't waste your money unless you can completely seal the room. also pergo is horrible in a theater and cold to the feet in a basement, go with a low pile commercial carpet.

 

[bspaulding]

Quote:

Originally Posted by BeerParty So, just to make sure I understand you correctly: the room will still have the windows and glass door after you have finished the room? If that is the case, any attempt at soundproofing is probably useless. The issue is called 'flanking', and you can read about it at a bunch of different web sites. When talking about soundproofing a room, the analogy usually used is a fish aquarium. Think of the ceiling, walls, and floor of your room like the walls and floor of an aquarium, where sound is the water. Any gaps in the soundproofing (like your windows and doors) are like holes in the walls of the aquarium. No mater how thick the rest of the walls of the aquarium are, it will not hold water if there is a hole in the wall. Your windows and glass doors represent big holes.

Hey Chris - thanks for quick response. Indeed, the windows and patio door are going to be there, and are my biggest concerns. Small chance I could eliminate the window, but only if it produced significant benefits controlling sound. I had all but thrown in the towel before seeing a thread involving Ted White that specifically discussed similar issues. I haven't posted enough to be able to include the link, but it is post #6 of the "Basic sound-proofing for multipurpose HT room" thread.


I suppose the question is more of a sound abatement one, and the degree of success I might achieve. Given the patio doors are right beneath my daughters' bedroom, I could almost not be dealing with worse conditions. Are all efforts to reduce the noise useless? If I can't truly soundproof, it would still be beneficial to take whatever steps would help avoid disturbing family members sleeping above during action movies, while entertaining, etc. -- and no more steps than those to avoid wasting money. e.g., still DD + GG Ceilings, but forget the walls? likewise with clips + hat channels?


thanks!

 

[bspaulding]

Quote:

Originally Posted by malovich I'm not a jedi master, maybe anakin when he was a slave where the general public may be a fetus in comparison but don't waste your money unless you can completely seal the room. also pergo is horrible in a theater and cold to the feet in a basement, go with a low pile commercial carpet.

malovich, thanks for your input. yes - per my response to Chris, I understand and agree that soundproofing per se is a lost cause, but I am striving to reduce noise transfer to the upstairs as much as is practical. Certainly would not like to waste any money on a lost cause, so your advice is appreciated.


Also appreciate the comment regarding pergo; however, my family has bad indoor allergies, so carpet is unfortunately not an option. Since the room opens out onto our backyard, we've been trying to get something that balances acoustics, durability, comfort, aesthetics (not that pergo is the most beautiful thing in the world, but you get my drift), and any other factors we should consider.

 

[mspat]

Can any one tell me about Monitor Audio Speaker Sliver and how to cover a false wall and what is a Fabric Retention System I think this installer is trying to rip me off he wants 1200.00 to perwire my media room 1800.00 to hook everything up and i check his quotes out and they r all over price. I am going with the JVC Professional Projector and the Black diamond Screen pls help me I really need to get this wall cover asap

 

[BeerParty]



Quote:
Originally Posted by bspaulding /forum/post/20800377


If I can't truly soundproof, it would still be beneficial to take whatever steps would help avoid disturbing family members sleeping above during action movies, while entertaining, etc. -- and no more steps than those to avoid wasting money. e.g., still DD + GG Ceilings, but forget the walls? likewise with clips + hat channels?

If you have a glass door and windows, the sound will go out the door and window and back into the house through its windows. Any effort you put into the walls or ceiling of a room is wasted unless you deal with the whole room.


About the only thing that might help (a little bit) is making sure the ceiling isn't transmitting the sound. You do that by loosely stuffing it with insulation before you add drywall to the ceiling.

 

[bspaulding]

Chris,


Sorry for my delayed response. I appreciate your guidance. From my research, it seems like the biggest flanking challenge will be transmitted via the structure vs. airborne -- or is there some way the airborne sound is able to make a "u-turn"?


Thanks!

Bryan

 

[BeerParty]



Quote:
Originally Posted by bspaulding /forum/post/20936583


From my research, it seems like the biggest flanking challenge will be transmitted via the structure vs. airborne -- or is there some way the airborne sound is able to make a "u-turn"?

When talking about soundproofing, the main concerns are (first) openings in the structure and (second) the structure itself. Your the windows and door create openings that the sound will travel through. Sound does not travel in a straight line, it spreads out in waves. If you have done some research, you will have read up on 'flanking' - in your situation the main flanking path will be through the windows and the doors.


Here is a quick experiment for you to try out: Outside the window, start a loud noise maker (a gas lawn mower or similar). Go inside and close the windows and doors in your room. Walk to a part of the room where you cannot directly see the object making the noise. Can you still hear the noise? Where does it sound like it is coming from? I'll bet you can hear it, and it sounds like the noise is coming from the window.


On the other hand, you might not be able to hear it. If you have really good windows and doors, they might not be your main flanking path. In dedicated theaters a lot of the builders here use exterior doors with thresholds to reduce the sound transmitted through the door. If you can't hear the noise, then your soundproofing job just got a lot easier.

 

[bspaulding]

Hi Chris,


I don't have the sliding door or windows yet, and close to the cross roads where I need to decide what's worth doing.


If there are special thresholds I could use, do you know where I could check them out?


Earlier, you indicated that insulation might be the only thing that would help. Besides this, to confirm: on account of the big holes created by the windows and doors, I may as well do single vs. double dry wall, use no green glue, no decoupling via clips/channels (instead screw straight into studs/joists)? The sound reduction in the bedrooms would not be reduced/abated in any meaningful way?


Thank you,

Bryan

 

[olyteddy]



Quote:
Can Some Jedi Masters Comment on My Remodel Plans?

You do realize that, sadly, just like Santa Claus and the Easter Bunny that 'Jedi Masters' are fictional characters?

 

[magicjuan74]

48" on center is pushing it for the hat channel on the ceiling. I would not go more than 24". However, on ceilings 16" on center is typical.

 

[BeerParty]



Quote:
Originally Posted by bspaulding /forum/post/20945672


Earlier, you indicated that insulation might be the only thing that would help. Besides this, to confirm: on account of the big holes created by the windows and doors, I may as well do single vs. double dry wall, use no green glue, no decoupling via clips/channels (instead screw straight into studs/joists)? The sound reduction in the bedrooms would not be reduced/abated in any meaningful way?

Pretty much. If your room will have standard glass windows and sliding glass doors, anything beyond insulating the ceiling and walls (interior and exterior) and making sure the interior doors are well sealed (when closed) is not likely to decrease the sound transmitted to the rest of the house.