Poor control room dimensions due to amount of gear!

[knightfly]

Eric, the materials I'm aware of here (home construction types) are 30 pounds per 100 square foot "tar paper", usually called building felt or roofing felt, and 90 pounds per square foot "roll roofing", similar stuff but usually comes with gritty stuff embedded in one side (the side one would walk on) - it sounds like what you're referring to may be similar but for fusing together with heat after application, to form a continuous layer?

As always, I appreciate your inputs - if I'm not careful, I may actually LEARN some of this stuff ... Steve

[Eric_Desart]

It's this stuff on top of this roof:

But only the top layer has this gritty stuff.
Such roofs are made of more than 1 layer. The bottom layers don't have this gritty stuff and are sold in all kinds of qualities and thicknesses.

Acoustic versions are based on this stuff, with possible additives to increase density and keep it weak at minus temperatures (In centigrade).

The acoustic quality is defined by the internal damping which is very temperature dependent.
PVC can't beat those properties. So PVC is used for it's other mechanical properties when necessary.

For the industry those bituminous acoustic versions are used in enormous amount. It exists in self adhesive versions and so on. Industrial steel noise enclosures seldom use PVC to improve the acoustic steel properties.
Ducting insulation (this alu sheeting you see round all those huge ducts in the chemical industry) based on metal or alu sheeting is in 95% done with this stuff. The automotive industry (busses, trains etc...........) use it.

Just to insulate the vacuum ducts for cooling compressors of one medium large power station I once used > 35000 sft.

Best regards
Eric[/img]

[fbars]

Eric,

I believe the materials we are all talking about, are the same. As Steve has said, we call it "tar paper" and "asphalt shingles". Both are available in different thicknesses, such as 30 pound and 50 pound. "Asphalt shingles" is the material with the grainy "stuff" on the side facing the sky , so to speak! The "asphalt shingles" are also available in roll form. In talking with a roofing contractor, the roll form is mostly used on a flat roof having no pitch (or very little). Sometimes used on a pitched roof to save cost.

This contractor prefers to roof homes and buildings during the US summer months. Though it can get very hot up on the roof as we know, his thoughts are to "shingle" in the early morming hours, so the crew has done the days "work" by 11:00 am. The two reasons for this being the shingles will mold or glue themselves to one another from the heat of the sun, and to NOT walk on them when hot, so the grainy stuff is not disturbed.

After typing all this, I just realized that you probably already know this!
My apology to you if so. I will check further in to using this material.
Thanks again,

Tom
First Bass Audio

[Eric_Desart]

Tom,

To make this sure:

If I call it "Tar paper" than every English speaking guy understands it correctly?

Bit surpriced since I don't see where the paper comes in (there's no paper involved).

TIA
Eric

[AndrewMc]

I used the stuff eric is describing in my outside walls. Because the exterior walls are cladded with OSB I wanted to increase the mass so I put 2 layers of roofing felt between the studs and caulked it all around and then added a layer of 5/8 drywall on top of that.

The roofing felt comes in rolls - a fraction of the cost of mass loaded vinyl (something like $12 a roll) - each roll is almost too heavy to carry by hand - I think I had to use a wheelbarrow. It has lots of little stones on the surface of it. Each roll did 5 or 6 stud widths 2 layers thick.

It's also class A firerated. I did a test with a blow torch and it melts and burns if the flame is on it but take the flame off and it instantly stops burning (doesn't propogate fire) - so I felt ok using it.

It seems to work. My inside walls have 3 layers of 5/8 drywall. Playing drums as loud as possible plus guitars on max volume - faintly can be heard directly outside the building. 10 feet away - can't hear a thing

[knightfly]

Eric, the name "tar paper" is an old one, from when similar materials were used to wrap houses before the exterior siding was applied - it was used for a vapor barrier, and really was tar coated paper at that time. Since then, this (lighter weight than the outer layer of roofing stuff) "tar paper" is usually found in what is called 15 pound and 30 pound weights - these are weight per "square", which in US is 100 square feet - so weight per square foot would be 0.15 lbs and 0.30 lbs respectively.

The actual exterior roofing material is made similarly ( bituminous impregnated felt) but is typically 90 pound (0.9 lbs per sq. foot) - the 15 and 30 pound stuff is normally used either as a vapor barrier under siding (instead of Tyvek) or for the same purpose under heavier, 3-tab roofing shingles for pitched roofs.

Sorry for the non-metric numbers, I'm just getting off graveyard shift with two more 12-hour nights to go... Steve

[seamus]

Very old thread, but...

Is this what you are talking about as a Sheetblok alternative:
http://www.homedepot.com/Building-Mater ... ogId=10053

...or the lighter stuff:
http://www.homedepot.com/Building-Mater ... ogId=10053

Thanks,
Seamus

[Xalky]

Very old thread, but...

Is this what you are talking about as a Sheetblok alternative:
http://www.homedepot.com/Building-Mater ... ogId=10053

...or the lighter stuff:
http://www.homedepot.com/Building-Mater ... ogId=10053

Thanks,
Seamus

Nope.

He's talking about Modified Bitumen roofing. It's sometimes called "torch down" here in the states. It's fairly thick, 3/16"-1/4"in thickness. You can get it granulated or without granules. It needs to be applied to the roof with a torch, and therefore not widely available to the general public. It's usually only available at roofing contractor supply houses.

[seamus]

Ah ha.
Thank you.
Seamus.

[seamus]

One more thing about this stuff...
If you were to use it in some sort of bass trap configuration....
Doesn't it stink like hell?