Reply
 
Thread Tools Display Modes
 
Old 10-31-2019, 04:59 PM   #1
Skoolie
 
Join Date: Apr 2019
Location: A bus
Posts: 104
Year: 2003
Coachwork: Thomas
Engine: Cummins 5.9 + Allison 3060
Rated Cap: Full size
Pink stuff for roof insulation

I don't see many threads about using the pink stuff. I got a very good price on it and plan to cover it with t&g. I'll seal the seams then stain. It loses thickness but gains insulation per inch when compressed. In a test area, we were able to maintain a 60 degree difference between indoor and outdoor temp at the ceiling.

Any reasons why not to do this?
OlgaAK is offline   Reply With Quote
Old 10-31-2019, 05:52 PM   #2
Bus Crazy
 
Ronnie's Avatar
 
Join Date: Oct 2017
Location: Virginia
Posts: 1,097
Year: 1971
Coachwork: Wayne
Chassis: International Loadstar 1700
Engine: 345 international V-8
Pink stuff? I assume you mean the pink fiberglass insulation used in homes? I used three inch, compressed to 2" in my bus. Not by any means saying that is the best idea, it is just what I did.

3" is normally 13 "R" value. So do you mean 13 R would be more if compressed? I thought it lost some when compressed.
Ronnie is offline   Reply With Quote
Old 10-31-2019, 06:00 PM   #3
Skoolie
 
Join Date: Apr 2019
Location: A bus
Posts: 104
Year: 2003
Coachwork: Thomas
Engine: Cummins 5.9 + Allison 3060
Rated Cap: Full size
This is 9", compressed to about 3". My busmate did the research on R values and I don't know the details. Just that it's a hell of a lot more comfortable in that area than the areas that don't have it. The original stuff we pulled out is 1" thick and looks like what you might find in an old sofa.
OlgaAK is offline   Reply With Quote
Old 10-31-2019, 06:12 PM   #4
Bus Crazy
 
musigenesis's Avatar
 
Join Date: Jan 2019
Location: Philadelphia
Posts: 1,395
Year: 2003
Coachwork: International
Chassis: CE 300
Engine: DT466
Rated Cap: 65C-43A
Compressing fiberglass insulation reduces its insulating properties, such that there is no point to compressing it - in other words, 9" of fiberglass insulation compressed into a 3" thickness will not have an R-value better than 3" of uncompressed insulation (and it will likely be even worse).

In general, insulation (of whatever kind) works because it traps tiny pockets of air; over-compressing insulation ruins this.
__________________
Rusty 87 build thread
musigenesis is offline   Reply With Quote
Old 10-31-2019, 06:17 PM   #5
Bus Crazy
 
Ronnie's Avatar
 
Join Date: Oct 2017
Location: Virginia
Posts: 1,097
Year: 1971
Coachwork: Wayne
Chassis: International Loadstar 1700
Engine: 345 international V-8
I just found a chart online and musigenesis is right, thicker compressed to 3" is about the same as 3" not compressed. My 3" compressed to 2" (because it is what is readily available) comes out to about 9 "R" value.
Ronnie is offline   Reply With Quote
Old 10-31-2019, 06:25 PM   #6
Skoolie
 
Join Date: Apr 2019
Location: A bus
Posts: 104
Year: 2003
Coachwork: Thomas
Engine: Cummins 5.9 + Allison 3060
Rated Cap: Full size
Thank you for the info. I will consider adding more insulation on the outside if needed.

I am still interested to know why people do not seem to commonly use this stuff.
OlgaAK is offline   Reply With Quote
Old 10-31-2019, 06:46 PM   #7
Bus Nut
 
Join Date: Sep 2018
Posts: 734
Year: 2007
Coachwork: Thomas Built
Chassis: Minotour
Engine: Chevy Express 3500 6.6l
Condensation. A bus doesn’t breathe the same as a house. The only way I see that it could work is if were fully encapsulated in plastic film. They sell stuff like that. If you use it seal the cut ends.
Danjo is offline   Reply With Quote
Old 10-31-2019, 06:46 PM   #8
Bus Crazy
 
musigenesis's Avatar
 
Join Date: Jan 2019
Location: Philadelphia
Posts: 1,395
Year: 2003
Coachwork: International
Chassis: CE 300
Engine: DT466
Rated Cap: 65C-43A
Quote:
Originally Posted by OlgaAK View Post
Thank you for the info. I will consider adding more insulation on the outside if needed.

I am still interested to know why people do not seem to commonly use this stuff.
It's about R-3 per inch vs. R-4 or R-5 per inch for EPS or XPS foam board. When head room is tight, you really can't get away with fiberglass.
__________________
Rusty 87 build thread
musigenesis is offline   Reply With Quote
Old 11-03-2019, 03:18 AM   #9
Bus Crazy
 
Join Date: Sep 2015
Posts: 1,177
Year: 2002
Coachwork: Thomas Built Bus
Chassis: Freightliner FS65
Engine: Caterpillar 3126E Diesel
Rated Cap: 71 Passenger- 30,000 lbs.
Besides, the loose fiberglass is itchy to install and plays havoc on your lungs if inhaled ... and you can believe there WILL be fiberglass dust generated in the installation.
Native is offline   Reply With Quote
Old 11-03-2019, 03:53 AM   #10
Bus Geek
 
EastCoastCB's Avatar
 
Join Date: Sep 2014
Location: Eustis FLORIDA
Posts: 19,088
Year: 1999
Coachwork: Thomas
Chassis: Freighliner FS65
Engine: Cat 3126
Rated Cap: 15
Quote:
Originally Posted by OlgaAK View Post
Thank you for the info. I will consider adding more insulation on the outside if needed.

I am still interested to know why people do not seem to commonly use this stuff.
cause eventually it can get nasty. It can grow mold. You get much better service from closed cell foam products so most folks use those.
__________________
.
Roll Your Own Build Thread
EastCoastCB is offline   Reply With Quote
Old 11-03-2019, 07:03 AM   #11
Bus Crazy
 
musigenesis's Avatar
 
Join Date: Jan 2019
Location: Philadelphia
Posts: 1,395
Year: 2003
Coachwork: International
Chassis: CE 300
Engine: DT466
Rated Cap: 65C-43A
Quote:
Originally Posted by EastCoastCB View Post
cause eventually it can get nasty. It can grow mold. You get much better service from closed cell foam products so most folks use those.
It's weird, you've seen how rusted my bus is, but every piece of fiberglass insulation looked brand-new from the factory, not a hint of mold. I wonder if the mold is more common in slightly-leaking buses where a tiny bit of water gets in and sticks around, vs. buses like mine that quickly become self-draining.
__________________
Rusty 87 build thread
musigenesis is offline   Reply With Quote
Old 11-03-2019, 07:27 AM   #12
Bus Crazy
 
Ronnie's Avatar
 
Join Date: Oct 2017
Location: Virginia
Posts: 1,097
Year: 1971
Coachwork: Wayne
Chassis: International Loadstar 1700
Engine: 345 international V-8
Non of the insulation was moldy in my bus. The walls were rather skimpy, so replaced all the wall insulation. The new fiberglass does not itch. Oh the old stuff itchy.... I remember doing an attic in the summer once. That was just awful.
Ronnie is offline   Reply With Quote
Old 11-03-2019, 09:47 PM   #13
Bus Crazy
 
Join Date: Sep 2015
Posts: 1,177
Year: 2002
Coachwork: Thomas Built Bus
Chassis: Freightliner FS65
Engine: Caterpillar 3126E Diesel
Rated Cap: 71 Passenger- 30,000 lbs.
Quote:
Originally Posted by Ronnie View Post
Non of the insulation was moldy in my bus. The walls were rather skimpy, so replaced all the wall insulation. The new fiberglass does not itch. Oh the old stuff itchy.... I remember doing an attic in the summer once. That was just awful.
Good to know the new stuff does not itch.
Native is offline   Reply With Quote
Old 11-17-2019, 01:09 AM   #14
Skoolie
 
Join Date: May 2015
Posts: 152
Foil bubble foil gets you a great r value. Easy to work with and you canDouble it up.
Dirtdoctor is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Powered by vBadvanced CMPS v3.2.3

All times are GMT -5. The time now is 05:25 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
×