Sand in Walls for a drum room ?

Since my original post got canned by the hackerz before everyone could respond (!), I'll take a slightly different tack. I've read as many of the posts here as I could, and think I know what I want to do to build a small drum practise room in my garage. My drum teacher suggested using sand to block out the sound, but from what I have read here it would appear that I would be better off with glasswool insulation instead of sand, between two layers of plasterboard. Is this correct, or have I picked up something wrongly ?? (I am working on the basis that glasswool would mean I have mass-air-mass, but filling with sand would just give me MASS) Maybe I can also mention what I plan to do and if it sounds just plain wrong, I'd be happy for anyone to correct me. I want to build a drum practise room in my garage. The garage is a brick veneer double car, single storey structure. It is built on a concrete slab and this slab forms the support for the garage and our house. The wall between the house and garage is insulated, as are all the external brick veneer walls of the house. The garage has some normal steel doors, which face out into the street. Opposite the garage doors are no houses, just a bit of a sloping embankment. Our garage is 650mm from the side boundary, and on the other side is a carport, partly bricked, and the neighbours house - another brick veneer. The garage has no windows, just a ventilation slot on the wall nearest the neighbours. It has a ceiling of some building board a few mm thick. Substantial room tiles further up. What I would like to do is build a ~ 2.2m cube to play in. No midnight sessions - should all be in normal day/evening times. I was planning on using 70 x 35 mm pine to build a frame. Fill the frame with insulation such as :- http://www.insulation.com.au/INSULCO/IN ... mBatts.pdf And then put gyprock sheets (13mm instead of 10mm) on the inside and outside of the room. Floor would be build from the flooring sheets which are available locally, with glasswool insulation between the flooring studs, which would be sitting on neoprene. Ceiling would probably be similar to the walls. I'm hoping that this will give me enough sound reduction without breaking the bank.

what is brick veneer? How heavy is it? sand between two leafs of gyprock is difficult to construct. You would get massive side force from the sand on the sheets. It would probably be a leaky construction because the sand won't fill the construction completely. Why not built a plastered 10 cm brick construction with a heavy ceiling?

bert Stoltenborg:

sand between two leafs of gyprock is difficult to construct.

It's good to put sand inside concrete block. But never put it in a gypsum/drywall wall. At one time or another lots of people seem to have this idea about putting sand behind gypsum, including me. :oops: Rod Gervias once wrote somewhere that it's impossible to construct. There's like a couple hundred pounds of force on the bottom of the wall against the gypsum, and it's not strong enough to hold it back, so the wall eventually 'explodes' (my word). Ahh, here's the link with comments by Eric and Rod: http://forum.studiotips.com/viewtopic.php?t=397

Wolf-man, your proposed construction (two 13mm gyprock on 70mm studs) would only give you about 20 dB of isolation at lower drum frequencies, with about 40 db at snare and cymbal ranges; and this is WITHOUT subtracting the negative effect of your existing construction, which would cause other problems due to multiple leaf effects - This would mean that (at kick drum frequencies) you could start hearing the drums outside when you were playing at around 70-75 dB; typical levels for a drum kit are more in the order of 100-110 dB, so they would be pretty loud outside. For Bert; scroll down to "Brick veneer" section, here http://www.saecollege.de/reference_mate ... 0Chart.htm I'm not positive, since I've not had first-hand experience with this type construction; but I think the brick is laid on edge, and ties placed every so often, mortared in place, and tied to the stud frame - I'm not sure how it rates so high on STC, because even with the mass all brick construction I've seen uses "weep holes" at the bottom to allow drainage of all the water brick is known to absorb - maybe John can shed more light on this, being it's his "stomping grounds", and all... Steve Wolf, if your construction is like the example at the above link, your walls are already about 13 dB BETTER than your proposed additional at low frequencies; you may be better off just adding more mass to the inner leaf of the existing wall. The garage door is another PITA to consider...

Folks, thanks for your help and your comments. It confirms what I thought after reading quite a few articles here - ie avoid using sand in the walls, and stick to 'normal' insulation. Knightfly, maybe my description was poor. The existing double garage is brick, while the house is brick veneer. Sorry about that, late night typing is never a good idea. The garage is a single brick construction on concrete slab. I initially thought about trying to treat the whole garage, but thought that since it is much bigger than I need, it would be too expensive to do the whole thing. Plus the two steel roller doors would leak too much noise, regardless of what I did for the walls. The floor would be tricky anyway, since half the garage is going to have a car in it. Hence my thought of having a little cube inside the garage, and it was/is my hope that if I can cut the noise down decently coming through the cube, the garage will do a little more to reduce the noise going through to our house (less of a concern) or out into the neighbours place. From what's been said, do I understand that the garage could make the noise coming out of the cube worse, or have I misunderstood. What do other drummers do at home ? I'd just be surprised if they all built really, really good soundproof practise rooms. cheers,

A lot of them seem to bite the bullet and get electronic sets for practice; I have both, but definitely prefer the real thing most of the time. If you're not trying to do the "night-thrash" thing, you might be able to use the existing brick for at least one wall - if there are weep holes along the bottom, they will reduce the effectiveness by at least 10 dB though. For that portion of the new room, I'd go for a separate stud frame with at least 8 inches to the inside edge of the frame, then two or three layers of gyprock on that - air space should be at least partially filled with insulation, and the insulation should be in good contact with the inner surface of the gyprock to help dampen the panels. If you have enough headroom, you could put a 2x6 (140 x 35mm) ceiling frame across the tops of your inner walls, and hang at least two layers of 15mm rock on that; fill above with heavy insulation. It's possible that leaving your garage door OPEN could actually work better than closed, depending on too many variables for my brain; thing to do is build it as heavy as you can afford, then try both ways... Steve

Thanks Knightfly. I'll need to see what I can squeeze in to the space. Going slightly at a tangent here, is there any good advice on this forum about actual construction details of keeping inner and outer studs seperate ? I understand that the more isolated I can keep the inner and outer walls the better, but I'm not clear about how to connect the studs together. Sigh, text is difficult to get this stuff across clearly. If I have an inner vertical stud and an outer vertical stud, they would both be connected to a top and bottom stud running horizontally. Now if they are both connected to the same horizontal stud at the top and bottom, wouldn't the horizontal members transmit sound from the inner wall to the outer ? I haven't seen any diagrams here making it clear just how to deal with that - unless you had totally seperate frames for the inner and outer walls, but I imagine that would be difficult to do. Thanks for your continued help. I doubt I would go the electronic drum route - just bought a nice acoustic kit to learn with, and doubt I could afford an electronic kit which would be similar enough in feel to the 'real' drums. cheers,

Hopefully this photo will work. My house is on the left. I am planning to build in the right hand side of my garage. Neighbours house is on the right.

There are some references and drawings on wall sway brackets in this thread http://www.johnlsayers.com/phpBB2/viewtopic.php?t=839 somewhere around page 15, plus or minus... Steve