? About using Dynamat on interior roof

[Rallye455]

When installing dynamat on the interior roof, should the factory insulation be removed first or do you just over top of it? Car is a 72 442 if it matters

[toxicz28]

I would suggest removing the factory insulation. That's what I did.

[Rallye455]

Thats what I figured...I just got finished...tried scraping with no luck used a 4.5 angle grinder and a wire wheel, made a huge mess but....still have to wipe it down and apply the Dynamat. thanks guys....

[zman1969]

My 69 bird had a alost like cardboard-jute type that came off easy with a body filler spreader -still a mess! took a good bit to blow it all out-glad its done

[nvmyss]

I did not have much luck with the Dynamat extreme on my roof. For prep I removed the old with a putty knife and wiped/scrubbed with toluene. When I applied I used hand roller and some heat, I then put a layer of the foam membrane type on that with some spray glue.
When I was done it looked all purty, but after sitting out in 120 deg heat on black car for a day, ½ of it has fallen down. The backing just melted.

Good luck with yours let us know how it works out

[Yoda4561]

Yeah your roof's sheetmetal was probably over 200F at that point. My truck has red metallic paint, and it hits around 180 on a 100 degree day here in Florida. You might want to check with second skin, their butyl formulations are supposed to be good for much higher temperatures than dynamat extreme.