| Insulating coach [message #229227] |
Sun, 10 November 2013 23:30  |
JJUNKSELL
Messages: 58
Registered: July 2013
Location: MERIDEN CT
Karma: 0
|
Member |
|
|
Hi all Im insulating the walls and ceiling of my pb. Im using the 1 inch foil backed (both sides) insulation and the bubble wrap foil insulation (redflux?)from home depot.I am stripping out all the old factory sprayed stuff down to bare alum or fiberglass, then cutting the 1 inch insulation to fit the space.It stays in place very well. What I would like is the opinions of the guys that have done this. or anyone else. Should I spray in the greatstuff type of foam insulation or just let it sit in the spaces? I am taping the foil wrap over the 1 inch insulation, so it is sealed. thanks Dave
Dave, 76 PB moneypit.Center of CT.
|
|
|
|
|
|
|
|
| Re: Insulating coach [message #229239 is a reply to message #229227] |
Mon, 11 November 2013 00:42  |
appie
Messages: 902
Registered: April 2013
Location: denmark
Karma: 2
|
Senior Member |
|
|
used this 1"
It is like fur, with hair standing out so it adjusts to the undlaying foam. glued it on with sprayglue
Does take up water if your coach is leaking though
http://www.scttrading.com/product.aspx?pid=1213
Appie
eleganza 76 "Olga" now sadly sold
6 wheel discbrake
Quadrabags
Springfield stage 2 462 olds
Manny tranny
( pictures at http://www.gmcmhphotos.com/photos/g6489-olga.html
Fulltiming in Europe july 2014 til july 2016
Denmark
[Updated on: Mon, 11 November 2013 00:43] Report message to a moderator |
|
|
|
|
|
| Re: Insulating coach [message #229274 is a reply to message #229227] |
Mon, 11 November 2013 09:32 |
Chr$
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
|
Senior Member |
|
|
The bubblewrap is useless in hot climates, fyi.
-Chr$: Perpetual SmartAss
Scottsdale, AZ
77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
|
|
|
|
|
|
| Re: Insulating coach [message #229283 is a reply to message #229227] |
Mon, 11 November 2013 10:34 |
rcjordan
Messages: 1913
Registered: October 2012
Location: Elizabeth City, North Car...
Karma: 1
|
Senior Member |
|
|
Check the flamespread rating on these foam products, most of them are pretty bad.
SOLD 77 Royale Coachmen Side Dry Bath
76 Birchaven Coachmen Side Wet Bath
76 Eleganza
Elizabeth City, NC
|
|
|
|
|
|
| Re: Insulating coach [message #229332 is a reply to message #229227] |
Mon, 11 November 2013 15:48 |
Chr$
Messages: 2690
Registered: January 2004
Location: Scottsdale, AZ
Karma: 1
|
Senior Member |
|
|
You should be able to find it at home centers. I prefer this stuff with the foil lining. I also added 4" of denim insulation to the roof and around the back under the bed...
The bubble wrap is also a waste of money. it is not cheap.
-Chr$: Perpetual SmartAss
Scottsdale, AZ
77 Ex-Kingsley 455 SOLD!
2010 Nomad 24 Ft TT 390W PV W/MPPT, EV4010 and custom cargo door.
Photosite: Chrisc GMC:"It has Begun" TT: "The Other Woman"
|
|
|
|
| Re: Insulating coach [message #229336 is a reply to message #229332] |
Mon, 11 November 2013 16:25 |
JJUNKSELL
Messages: 58
Registered: July 2013
Location: MERIDEN CT
Karma: 0
|
Member |
|
|
The po did most of the coach in bubble wrap. Im just untaping it and reusing it over the insulation im installing.I figured it would help a little, why throw it out? Thanks Dave
Dave, 76 PB moneypit.Center of CT.
|
|
|
|
| Re: Insulating coach [message #229339 is a reply to message #229336] |
Mon, 11 November 2013 16:48 |
Carl S.
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
|
Senior Member |
|
|
| JJUNKSELL wrote on Mon, 11 November 2013 15:25 |
The po did most of the coach in bubble wrap. Im just untaping it and reusing it over the insulation im installing.I figured it would help a little, why throw it out? Thanks Dave
|
Dave, I think you're on the right track with the insulation. The "Reflectix" is more of a radiant barrier than an actual insulation. I doubt that it has much, if any 'R' value, but it will reflect heat both ways and serve as a vapor barrier. It also adds another layer to the system and every layer acts as somewhat of a thermal break. Reflectix has a web site with lots of information on different applications. Like the other guys said, it is not going to be very effective as an insulator, but it can't hurt to have it in there in addition to the urethane foam you're planning to use.
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
|
|
|
|
| Re: Insulating coach [message #229346 is a reply to message #229339] |
Mon, 11 November 2013 17:47 |
 |
SeanKidd
Messages: 747
Registered: June 2012
Location: Northern Neck Virginia
Karma: 4
|
Senior Member |
|
|
law of diminishing returns apply to insulation..the R-1 reduces heat loss by 50%, R-2 of insulation brings you to about 67%, R-4 gets you 80% heat loss reduction...going to R-8 only gets you to about 93% 1" of closed cell spray foam (about R-7) will cover over 90% of your conductive heat loss.
radiant, and convective heat losses are your enemy too, GMC has a lot of glass (R-0.14) will benefit from reflective coatings for air conditioning load and thermal drapes for heat.
Sean (Certified Energy Manager) Kidd
Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
[Updated on: Mon, 11 November 2013 17:48] Report message to a moderator |
|
|
|
| Re: Insulating coach [message #229348 is a reply to message #229346] |
Mon, 11 November 2013 17:52 |
tphipps
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
|
Senior Member |
|
|
A very good liner for your curtins is ironing board material. The metallic side facing out will reflect heat back out the window, if the curtains are drawn. It also cuts down on the amount of outside light coming in the windows at night.
Tom, MS II
2012 Phoenix Cruiser model 2552
KA4CSG
|
|
|
|
|
|
| Re: Insulating coach [message #229379 is a reply to message #229346] |
Mon, 11 November 2013 20:33 |
A Hamilto
Messages: 4508
Registered: April 2011
Karma: 39
|
Senior Member |
|
|
| SeanKidd wrote on Mon, 11 November 2013 17:47 |
law of diminishing returns apply to insulation..the R-1 reduces heat loss by 50%, R-2 of insulation brings you to about 67%, R-4 gets you 80% heat loss reduction...going to R-8 only gets you to about 93% 1" of closed cell spray foam (about R-7) will cover over 90% of your conductive heat loss.
radiant, and convective heat losses are your enemy too, GMC has a lot of glass (R-0.14) will benefit from reflective coatings for air conditioning load and thermal drapes for heat.
Sean (Certified Energy Manager) Kidd
|
Yep. The single pane windows are going to loose a lot of heat.
HOWEVER, increasing the R-value from R-7 to R-10 is nowhere near the point where the law of diminishing returns kicks in for ceilings and walls.
I don't have the math available to dispute that R-1 reduces heat by 50% (although I am sure it does not), but I will argue that R-2 cuts the heat transfer in half over R-1. And every time you double the R-value, you cut heat transfer in half. That's how you reduce your residential heating and cooling costs by adding insulation to walls and attics.
If Sean's numbers are right, then by extrapolation, the amount of energy that you save by increasing your attic insulation from R-19 to R-38 would be a few hundredths of a percent. Empirical data disputes that.
Think of it his way: If a gallon of propane will heat a living space for three hours if it is insulated at R-7, it will heat that same living space for FOUR hours if it is insulated at R-10, and SIX hours at R-14.
|
|
|
|
| Re: Insulating coach [message #229384 is a reply to message #229379] |
Mon, 11 November 2013 20:49 |
Dennis S
Messages: 3046
Registered: November 2005
Karma: 2
|
Senior Member |
|
|
I have been using the Reflectix to add in voids around the windows, in areas where the factory spray is less than full and as a general layer under the FRP ceiling. With the coach parked in the sun, there is a noticeable difference in the heat transferred through the walls and ceiling. With the Reflectix the aluminum ribs conduct the heat to the interior and create a grid --
Just my experience.
Dennis
Dennis S
73 Painted Desert 230
Memphis TN Metro
|
|
|
|
| Re: Insulating coach [message #229398 is a reply to message #229227] |
Mon, 11 November 2013 22:40 |
Adrien G.
Messages: 474
Registered: May 2008
Location: Burns Flat, OK 73624
Karma: 1
|
Senior Member |
|
|
Dave,
If you don't use can foam to glue in the sheet foam, it will squeak as travel or could even do some as you walk in the coach.
I ended up using 2 layers of 3/4 foiled foam sheet. HD and Lowes didn't have 1.5" foam. The rear cap has too many curves, it's a good candidate for spray foam or other easier to form material.
Just what I did.
Adrien & Jenny Genesoto
75 Glenbrook (26-3) Mods LS3.70 FD / Reaction Sys / 80mm Front&Intermidiate / Hydroboost / 16" Tires / Frame Rebuild / Interior Rebuild
Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
|
|
|
|
| Re: Insulating coach [message #229422 is a reply to message #229379] |
Tue, 12 November 2013 04:21 |
|
SeanKidd
Messages: 747
Registered: June 2012
Location: Northern Neck Virginia
Karma: 4
|
Senior Member |
|
|
| A Hamilto wrote on Mon, 11 November 2013 21:33 |
| SeanKidd wrote on Mon, 11 November 2013 17:47 |
law of diminishing returns apply to insulation..the R-1 reduces heat loss by 50%, R-2 of insulation brings you to about 67%, R-4 gets you 80% heat loss reduction...going to R-8 only gets you to about 93% 1" of closed cell spray foam (about R-7) will cover over 90% of your conductive heat loss.
radiant, and convective heat losses are your enemy too, GMC has a lot of glass (R-0.14) will benefit from reflective coatings for air conditioning load and thermal drapes for heat.
Sean (Certified Energy Manager) Kidd
|
Yep. The single pane windows are going to loose a lot of heat.
HOWEVER, increasing the R-value from R-7 to R-10 is nowhere near the point where the law of diminishing returns kicks in for ceilings and walls.
I don't have the math available to dispute that R-1 reduces heat by 50% (although I am sure it does not), but I will argue that R-2 cuts the heat transfer in half over R-1. And every time you double the R-value, you cut heat transfer in half. That's how you reduce your residential heating and cooling costs by adding insulation to walls and attics.
If Sean's numbers are right, then by extrapolation, the amount of energy that you save by increasing your attic insulation from R-19 to R-38 would be a few hundredths of a percent. Empirical data disputes that.
Think of it his way: If a gallon of propane will heat a living space for three hours if it is insulated at R-7, it will heat that same living space for FOUR hours if it is insulated at R-10, and SIX hours at R-14.
|
adding insulation (R-7 to R-10) in your coach is a lot of effort for a 2% gain...what you will find is degraded cellulose foam in the rear section..most of what came out of the ceiling by the bathroom and rear section was black dust....there was no spray foam in these areas. for the front...reflectrix will do as its name implies and reflect infra red energy and add a minimal R-Value...it would need to be sealed from air leaks to provide any R improvement and for best results installed closest to the skin of the craft/building. Insulation (all buildings included) weak points are: improperly installed vapor barrier (condensation), air gaps, infiltration, conductive coupling and lastly, settled or crushed fiberglass/cellulose. a loosely installed 2" foam board (R-10)installed in a wall cavity has a actual system value of ZERO...if air can get around it (other than an engineered sealed dead space) the insulation will create a convection engine and equilibrium results.
Association of Energy Engineers Certified, CEM, CEA, CMVP, CDSM
Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
|
|
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
