705 VS ultratouch insulation, Isolation door questions

[Flynman]

Hello everyone!! I am done framing my garage studio and have some questions (pictures will follow). Am I better off with 705 in the walls or ultra-Touch cotton fiber insulation? Walls are seperate double 2x4 walls, 2 inch gap between the 2 walls, RC 8 channel on inside drum room wall, with double 5/8 sheetrock on each wall. Wondering which is the better route to go.
I am also thinking of modifing a hollow core door. I was going to take out bottom rail of door and then fill door with sand and then reinstall bottom rail. I will then reinforce door frame & hinges, install door seal kit. What do you think?

Thanks
Keith

[jwl]

Hi Flyn,

How is the sheetrock installed? Do you have all the sheetrock on one side for each wall?

As far as insulation between/behind walls, I would not recommend 705 as a cost-effective solution. It's great insulation but that would be extremely expensive, and the performance difference does NOT justify its cost. Ultratouch will work great, as will rockwool or even fluffy fiberglass. Look around at the different material costs in your area, and get whatever the best deal is. Though working with Ultratouch in this way is a breeze, so it gets bonus points for that.

I'd also add a layer of MDF and/or plywood to the door. I've never tried the approach you mention, it sounds like it could work though I'd be concerned about the door being "airtight" so sand doesn't leak out. That's a lot of weight pushing on thin wood. Personally, I think I'd feel better about just finding a decent solid core door and reinforcing that.

[Flynman]

Hey JW, Yes I have double 5/8 on 2 sides none on insides of double wall. I avoided triple & quad leaf problems. I can get the ultratouch locally for a resonable price. I was having problems finding flat solid wood doors locally. Adding the MDF to the door sounds like it might work. I'll download some pics in a few days.


Thanks

[Lissajous]

Ultratouch is good stuff and you can feel a little more environmentally responsible by using recycled products in your construction. Maybe you can get a LEED tax break =)

[bpape]

Agreed. No need to do 703 or 705 in the walls. UltraTouch is a nice solution if you want to do the green thing. And, since you can get it locally, why not. Standard fiberglass wall insulation will also work just fine.

Bryan