MDF as soundproofing

Matthew Will · 04-28-2003, 02:45 AM

Hello,
I am trying to construct a simple home theater in my basement that requires minimum construction. This is my parents house and I'm only 18 so I can't necessarily tear the place apart.

My problem is with my parents. I spend all this money on an impressive sound system and they complain about how loud it is and how things are shaking 2 floors up. Hehe..what can I say. I need something to do.

I'm not going to be able to stop all the vibrations because that would require a huge amount of work/money that I can't do. So if I have any goal it is to limit as much of the sound that bleeds through the basement ceiling. So here is my idea.

The ceiling is made of ceiling tiles with about 9-12" between the floor above. Could I construct a sound barrier between the two floors by laying MDF panels on top of the ceiling tiles? Like I said it prob wont limit the vibrations in hte house because I cant do anything with the walls and I can not isolate structural beams from resonating. I do believe the MDF panels would act as a sound barrier that reflects most of the frequencies. Therefore my parents would hear more of the bass instead of a muffled version of all the frequencies.

Also, do I need to put the panels in all of the ceiling tiles even behind the area in the room where the speakers are not aimed at? Perhaps I could only put the panels near where the sound is aimed at. Any replies are welcome. Matt

Darren_T · 04-28-2003, 09:43 AM

I wouldn't put anything as heavy and dense as MDF over my head

It wouldn't do a lot in my opinion anyway. The best thing to do would be to add more insulation in the space between the tiles and the floor above.

Darren

Dave Poehlman · 04-28-2003, 10:31 AM

Yeah, besides the weight issue, the MDF isn't too cost effective.

I would insulate the joists as stated above. Also, depending on the size of the room and your budget, you may want to look into replacing the ceiling tiles with sound reduction ones (Armstrong makes a nice tile.. but they can get pricey if you're looking at a large space)

Also.. you may want to insulate around any ventwork that might be transmitting noise.

Overall, try to determine how the sound is getting upstairs (vibrations, cold air duct, through doors, etc..) and attack that problem.

Matthew Will · 04-28-2003, 10:51 AM

Well the room im using for my home theater is faily large. It is sort of a Z shape and the section I am using for the viewing area is probably about 15 feet wide and 30 feet long. Is there a cheap insulation solution at home depot that most people use?

I found something that looks pretty interesting to me. If you go to www.mcmaster.com and then search for product 55075T21. When it finds it on the left, click on "Catalog page" and scroll down to see it. They're 36X36 sheets of fiberglass sound absorbing sheets. They have an NRC of .60 and only cost 3.26 per sheet. Does this sound promising? Matt

LaMarcus · 04-28-2003, 03:48 PM

This thread is great. I'm getting some good ideas. I think I 'm going to buy the acoustic tiles on that website. Looks like I should be able to do my theater for $150 tops. That's excellent! I think I want to get something else to go between the floor joist and the acoustic tiles also, so keep the ideas coming boys.

**HTF Ads**

Ted White · 04-30-2003, 04:17 PM

Actually, mass is your best friend right now. You want cheap mass, however. MDF is great mass, but as mentioned...too expensive for what you need it for. First reinforce the ceiling grid with more support wires, Then place drywall sections, probably cut the same size as the existing tiles so they nest into the track a bit. The drywall will be laid OVER the existing tile. Then fill the remaining cavity with plain old fiberglass insulation. This is the cheapest bang-for-the-buck solution.

Keep in mind your problem is bass transmission, and for that you need mass. Insulation alone won't do it. Drywall = cheap mass. The insulation is to reduce resonance that a hollow area can cause.

Ted
www.TedWhite.Homestead.com

ChrisWiggles · 04-30-2003, 06:12 PM

Absorption and sound proofing are two totally different animals. Absorbing materials, such as fibergass insulation and fabrics are great at absorbing, but not so great at stopping sound. They can help within walls and such, but alone they will do zilch. Ted's solution sounds like a good one. You want a couple heavy barriers, with prefarably a large volume stuffed with insulation. It is also important to seal everything, because if there are cracks and gaps in the ceiling, LOTS of sound will get through. A very suprising amount. It'd be best to tear out the tiles completely, and just put up a complete and finished drywall ceiling stuffed with insulation. Another idea that has floated around to block sound is heavy 80-lb roofing paper. Soundboard might also help a little. Not too sure on those last two counts though.

TimForman · 05-01-2003, 08:36 AM

Check out this thread.

DerekB · 06-01-2003, 05:31 AM

Has anyone tried using Acoustiblok (www.acoustiblok.com) for sound insulation. It seems to be very flexible for construction purposes, and their website claims that it's like lining your walls with lead. The product is not cheap, but it may work well if you want to install it above exisiting ceiling tiles, or between a sheetrock "wall-in-wall" configuration. I would be very interested in knowing if anyone has had experience with this product.

MarkLaf · 06-01-2003, 01:12 PM

I work for a building materilas supply company and I used some well I call it sawdust mat basiclly its sawdust glued together in 4'x8' sheets andy place that sells sheetrock wil sell it. And there is also a product called tectum looks like shredded wheat with insulation glued to one side that works the best out of anything I have used but it is very very exspensive!

Mark