Mason ideas for isolation

[hugo_inside]

I have been with a experienced mason and he told me some ideas for my practicing rooms. I told him about filling blocks with grout, and he told me to fill it with "CLINKER" (it's seem to be hollow balls of concrete)



and on ceilings, he told me to put poliestirene with concrete joist and I will be able to put the ceiling that I want after.





the idea is not to be easy of coming in to the practicing room over the ceiling, and isolate too...

And then block were painted on one side and sheetrock 13 mm atached on the inner side.

what do you think??

[knightfly]

Hugo, I saw your post on Home Recording; for the most part, these guys come to John, me, Rod Gervais, etc, for answers - so it may not be a good idea to take some of the suggestions too seriously -

Your mason friend may know masonry, and that will be a good asset as far as it goes - but he definitely does NOT know ACOUSTICS, and that can get you in trouble. His suggestion for the "clinkers" will make your block walls so you can't add air gap on either side with gypsum on a stud frame (if that's the way you decide to go) - because the clinkers will conduct sound from one side to the other WITHOUT any damping, and so would give you worse results than leaving the blocks hollow. The clinkers being hollow themselves, means that you've just made your wall as NON-isolated as possible, WITHOUT even getting the benefit of the highest MASS possible.

If you intend to do single leaf walls, the best way to do that is to fill the blocks with sand. Both sides of the blocks should be painted at least two coats for best sound blocking that can be had with just blocks.

If you intend to use a combination of blocks and a separate stud wall, the best way to do that is STILL to fill the blocks with sand, then put insulation/stud frame/gypsum, sealing with acoustic rated caulk and making sure that the stud frame has NO HARD CONTACT with the blocks. There are isolated sway braces that help hold walls apart with no hard contact.

The third possible way to do these walls is the famous STC 63 illustration, seen at the bottom of this page

http://www.domesticsoundproofing.co.uk/tloss.htm

This type wall is a double stud frame, with two layers of gypsum on the OUTSIDE of each frame, filled with insulation.

All three ways will give fair isolation, the filled block + frame and gypsum would be the best isolation, especially for LOW frequencies - I've still not found time enough to calculate which would be CHEAPER - perhaps you can figure this out on your own?

If you go with the concrete ceiling system your mason friend suggested, you should use the block/stud combination; this will give you the support you need for the concrete ceiling, and you can continue the inner stud frame across the ceiling for a true room-in-room construction. Floors should be at LEAST isolated with EPDM rubber, the deeper the air gap (insulated fully) between existing and new floor, the better isolation.

That's about all I have time for right now... Steve

[hugo_inside]

very good idea the EPDM. Is the material used on playpen no? (I don't know if this is the correct word, I wanna say the floor in some places where children play...)





is that correct??

[knightfly]

It's hard to tell by looking at a pic, but those could be made of EPDM - here's a link with some properties info -

http://www.azom.com/details.asp?ArticleID=1822

Not sure of sources on your side of the world, but Asia seems to be a possibility if there isn't anything local. I would try any local industrial gasket supply places first. What you want is at least 1/2", 55-65 durometer rating... Steve

[hugo_inside]

I think I found it yesterday, the man in the shop doesn't know the exactly name, but he thinks it's called EPDM or similar combination of letters

but my surprise was the price of this material ... the price of 1000 mm x 1000 mm x 20 mm panel is 116,55 € !!!!!

there was other thickness, but is so expensive too, 1000 mmx1000mmx10mm --- 56,23€

both prices in US dollars: 140 $ 1 square meter of 20 mm thickness
67 $ the same panel of 10 mm thickness

[knightfly]

That very well could be the right stuff - good elastomers are NOT cheap. That's part of why the Auralex U-boats are more than people think they should be; they're made of EPDM because it lasts about 25 years instead of 10 like neoprene... Steve

[RevMen]

I didn't even know you could purchase clinker by itself. Clinker is cement (not concrete) in the form it takes as it comes out of a cement kiln. It's usually ground up shortly after exiting the kiln into the fine dust that you can buy at a hardware store. I just happen to have worked at a cement plant, so I am familiar with the stuff.

It's definitely not hollow, it's just clods of cement. I can't imagine clinker having any acoustical benefits.

[hugo_inside]

definitively my mason friend don't know acoustics ...

[knightfly]

Hey RevMen, welcome; glad you chimed in, I thought that term was just another spanish one I'd not heard. Now that I know they really ARE clinkers, it doesn't change much of anything still not a good idea... Steve