Fastening Drywall

knightfly · Post by **knightfly** » Tue Jul 27, 2004 5:08 am

In that case I'd just add a layer of drywall - you could probably just use panel adhesive, and just strip-glue every 16" (like stud spacing) - this will avoid the new panel changing the coincidence frequency of the old by becoming "one piece"; if you just glue strips on spacing similar to studs, you maintain separate coincidence frequency for each panel and the wall has better isolation.

Putting another layer on RC, with only 1/2" air gap, would give you a mass-air-mass resonance of around 200 hZ - this could become a real pain to fix with treatment later.

The mass of the blocks and everything else should give you pretty good isolation as is, probably around STC 55 or so... Steve

smallstonefan · Post by **smallstonefan** » Tue Jul 27, 2004 5:12 am

Awesome info (as usual).

Thanks!

knightfly · Post by **knightfly** » Tue Jul 27, 2004 9:02 am

Glad you likee

was gonna post this link earlier and forgot; just when you thought it was safe to ask more questions...

http://irc.nrc-cnrc.gc.ca/practice/noi1_E.html

Enjoy... Steve

smallstonefan · Post by **smallstonefan** » Wed Jul 28, 2004 2:12 am

knightfly wrote:Glad you likee was gonna post this link earlier and forgot; just when you thought it was safe to ask more questions...

http://irc.nrc-cnrc.gc.ca/practice/noi1_E.html

Enjoy... Steve

Wow, some of that was unintuitive - such as actually reducing STC if you don't do the drywall right.

I'm losing me hair...

I think we're glue a 5/8" sheet of drywall to the original drywall/foam setup, unless you have a better suggestion...

knightfly · Post by **knightfly** » Wed Jul 28, 2004 9:41 am

In this case, that makes the most sense. When you do, assuming you don't have ANY wetness in that area, I would put the new layer resting on 1/4" thick spacers , do NOT spread glue on the entire panel but only 2-3" wide stripes running the same as studs (2" stripes if you use 16" centers, 3" if you use 24" centers) - spread the glue stripes on the existing wall vertically, set the spacers directly under each stripe, then screw the new panels onto the old using Type G, or gypsum, laminating screws to hold the new panel against the old til the glue sets - after that, you can mud over the laminating screws, caulk around the new panel, and finish (tape and texture, etc)

This will get you better isolation than full surface glue... Steve

smallstonefan · Post by **smallstonefan** » Thu Jul 29, 2004 12:47 am

Wetness has never been a problem. What do you recommend to use for the spacers?

Oh, we started ripping out drywall yesterday - we're finally started!

knightfly · Post by **knightfly** » Thu Jul 29, 2004 1:02 am

If you have some 1/4" plywood scraps they're perfect - if not, you can rip 1/4" slices from a piece of scrap 2x lumber - the plywood is much easier if you don't have access to a table or radial saw, though... Steve

smallstonefan · Post by **smallstonefan** » Thu Jul 29, 2004 1:03 am

I've got a table saw - we'll get it done.

Thanks.