The Stovebolt Site Forums The Shop Area Interiors which way is up - sounddeadening material

I just finished putting dynamat-like material all over the cab of my '52 pickup. Now I want to put a layer of the insulated jute with foil on one side over top of the dynamat. This may seem like a dumb question but which way do I put the jute material with foil backing? Does it go shiny side down or up?

According to the experts per the tech. articles, the foil side goes up and is exposed to view. I have been following the restoration of a fifties Chevy at Chevy Duty's showroom and they installed the foil side up. Also, the tech. article in Classic Truck magazine shows the foil side up. Maybe it is the same concept as insulating a house, the foil side or kraft paper side is to the inside of the house. I have done the interior of my '66, C-10 cab with the foil-face insulation you are talking about (from Chevy Duty)and put the foil side up so you can see it.

What did you use instead of Dynamat? I'm sure others will chime in for a few more opinions. Good luck with your project.

I agree with LILRED66, except I would describe it as the foil side is towards the inside (as LILRED66 said, as inside a house) - this is completely correct, even for the ceiling/roof of the truck (where "up" might be interpreted incorrectly).

Make sure the mat is completely glued to the outer surface and make sure all seams are sealed (so that moisture cannot get between the mat and the metal).

Tim

This is a good question. I purchased -- as yet still uninstalled -- some insulating material from JC Whitney. Directions -- admittedly poor ones -- state that the foil should go towards the scource of heat -- in the case of floors and firewall this would mean to me that the foil would be down on the floors and against the firewall -- the picture seems to bear this out.

twe56,

Call the manufacturer and tell them the different locations you want to place the insulation. I have done it and gotten all sorts of answers.

I bet the JCW suggestion is for an engine compartment (and for CA/NM/AZ).

Here is the best answer: use insulation that has foil on both sides - you can't go wrong as to which side goes in which direction in which part of your vehicle in which part of the country in which part of the year.

The hot/heated side is not a very helpful guideline but it seems to be the answer most often given.

Tim

This is a picture of ceiling insulation in my Suburban.

Below is a photo of the ceiling from another suggestion.
[img]http://ares.cs.siena.edu/~lederman/truck/Photos/Reassembly/ceilinsul1.jpg[/img]

Thanks for the suggestions all.

The stuff I used instead of dyanamat is a product called B-Quiet, I found a supplier of it here in Canada which cost at least
half the price of dynamat. It seems to be the very same stuff really, just a different name.
I guess I should just put aluminum foil on the non-foiled side then no matter what way I put it in would be correct.
I'm gonna have to start ordering from places that put a few instructions in with the items.

i wouldn't do that. you want the insulation you used to bond to the metal to keep it from vibrating to help keep the noise down. if you cover it in foil it cannot bond, and the effect would be greatly diminshed.