Use of JM 800 Series Spin-Glas® equipment and external duct insulation

[Deleted member 32]

I've been given 2 large pallets of Johns Manville 800 Series Spin-Glas® equipment and external duct insulation board. The r-value is 4.3 and the boards are faced. I know NOTHING about insulation and was wondering if I can use it for the ceiling in my attic. My attic is wired and floored and ready to build rooms in aside from insulation, drywall and top flooring. HVAC lines/electric is already ran and I just need to have the unit/ducts installed. This is the description from JM's website:
Johns Manville 800 Series Spin-Glas® equipment and external duct insulation provides a broad range of solutions to meet your unique application needs. The breadth and depth of our product availability includes plain, FSK, AP (ASJ), or Ultra (poly-top) faced board, where the facing acts as a vapor retarder. You can be assured you are getting the same superior performance from the facing as the insulation because we manufacture both to the highest quality standards. 800 Series Spin-Glas board is easily fabricated for an excellent finished appearance on duct and equipment systems.

JM Spin-Glas Fiberglass Board White Matte, 3 pcf Density, ASJ, 48 in Length, R-Value: 4.3, 1 in Thickness, 24 in Width

 

[RidWan]

Look you can use it in the attic, but spin glas is technically for external duct or equipment insulation, not living space envelope and because it is dense and faced, it'll do something, but it's not really designed for thermal performance like your typical attic batt or blown in insulation nd then to the R value which is only 4.3 per inch, and if it's just 1" thick, you'd need to stack it (and that can get annoying fast), also, if you're planning on finishing the attic into livable space, you'll likely need to hit code usually R-30+ for ceilings depending on your zone., I hope this little will help

 

[Deleted member 32]

Look you can use it in the attic, but spin glas is technically for external duct or equipment insulation, not living space envelope and because it is dense and faced, it'll do something, but it's not really designed for thermal performance like your typical attic batt or blown in insulation nd then to the R value which is only 4.3 per inch, and if it's just 1" thick, you'd need to stack it (and that can get annoying fast), also, if you're planning on finishing the attic into livable space, you'll likely need to hit code usually R-30+ for ceilings depending on your zone., I hope this little will help

Very helpful.Thanks!

 

[BubbleWrapBandit]

Great analysis. You can definitely use it, but honestly, it's not the best fit for that job. The low R-value per inch and the hassle of stacking it up make it a real headache for attic use.

 

[Deleted member 32]

Great analysis. You can definitely use it, but honestly, it's not the best fit for that job. The low R-value per inch and the hassle of stacking it up make it a real headache for attic use.

Thank you. I decided to use a professional and have the proper insulation installed lol. Now I have two large pallets of this stuff sitting in my garage to get rid of lol. May use it in the garage or something.

 

[WrapAndTrap]

Great idea on getting a professional involved, it can really save you some trouble. Funny story, a friend of mine once grabbed a bunch of leftover duct board from a commercial project and decided to use it in his shed. It did a decent job of keeping the noise down, even if it wasn't the best for insulation, but he ended up putting it on the walls of his garage as well. I bet you'll find a good use for it too, or maybe you could swap it with a local HVAC guy for a case of beer

 

[Th3rmoPro]

I love your idea of using leftover duct board to reduce noise, it's really innovative. It's a clever way to repurpose materials and make the most out of what you have.