Waterproofing and sound deadening roof

As you probably know, our caprice got broken into in July.  Because of this, I am getting the headliner replaced and the roof repainted.

The body shop gave me a quote w/o removing the roof rack, and with removing the roof rack. Since they can mask it, the labour for removing the rack would be at my expense.  I figure I may as well do it right, remove the roof rack myself and:

1) reseal the rivnuts;  
2) put sound deadening material on the roof while the headliner is off; and
3) hit the roof rack parts with a "back-to-black" type product.

I don't have a leak in the roof, but may as well kill 2 birds with one stone.  I read the posts on this forum about the roof leak and the lowes sound deading and had a few questions.

- If I don't have a leak, should i just reseal the rinvnuts with caulking, or should I just replace them with the rubber well nuts while I'm in there?
- Should I remove the thin centre pieces of the roof rack ?  do those have rivnuts that need to be resealed ?
- Since the car is black, the roof skin gets unbearably hot in the summer, and it gets parked outside every day in the summer.  I don't think I want to use an asphalt based product on the underside of the roof because I'm concerned it would melt.  Any suggestions on another product, aside from the obvious Dynamat ?  Are there any dynamat knockoff products out there ?  I'm not opposed to using the lowes stuff on the floor when I pull the seats later this year.

thanks

Jason:

I would stick with the "ice shield". Kill two birds etc. Waterproofs the roof and deadens the tin canning of the sheet metal. Adding a 1/4 inch of upholstery felt will make it even better for sound deadening.

Used it in the Locomotive and it worked well on the floor. The stuff I used was the polyurethane based sheet (comes in rolls). Only caveat is when you remove the film from the adhesive, make sure its where you want it. That stuff sticks big time, especially after you roll it out.

Bill

Jason,I see zero negative effects from the heat.It is designed as a roofing product after all. (I personally used it in a 72 C-10 almost anywhere it would stick.)

convert2diesel wrote:

Jason:

I would stick with the "ice shield".  Kill two birds etc.  Waterproofs the roof and deadens the tin canning of the sheet metal.  Adding a 1/4 inch of upholstery felt will make it even better for sound deadening.  

Used it in the Locomotive and it worked well on the floor.  The stuff I used was the polyurethane based sheet (comes in rolls).  Only caveat is when you remove the film from the adhesive, make sure its where you want it.  That stuff sticks big time, especially after you roll it out.

Bill

Might work if it's polyurethane. I was worried about asphalt based stuff melting and unsticking in the summer since the adhesive is working against gravity, unlike applying it to the floor. that and seeping black ooze into the headliner.

is it worth removing the thin centre strips of the roof racks ? I'll remove the exterior ones that hold the cross-bars.

I did on mine and found many well nuts were dried up/brittle and desinagrating. Since you have everything apart, now is the time to do it. Use fresh well nuts and get an inch-pounds torque driver to secure the fastners so you do not over torque them.

You will most likely find a few rusty holes that will need some tending.

Take the time to resort your strips while they are off if they are faded.

I ordered the fabric to do the headliner. Can't source the Grace Ice and Water shield locally. I'll pick some up later this month in San Diego. I noticed home depot in the USA has High Temp Grace Ice and Water shield for metal roofs. I think I'll just get a roll of that.

It's probably really obvious when you have the roof rack and headliner off but how do you take out the rivnut ? Just punch it out and replace with a well nut ?

FWIW my two-tone has a black roof and I'm in Florida... and my peen 'n seal is fine. Doesn't smell. Can't tell it's even there.

Removing the rivnuts requires drilling them out. If the rivnuts are not rusty, just retighten them with a bolt, nut and washer. Do not use the wellnuts for the rack unless you want a "just cosmetic" one. The wellnuts do not have the strength to hold the rack on the car with anything on it. The rivnuts are metric, and the only place I found the metric rivnuts was on ebay. I think they are 5mm or 6mm (its been a couple of years since I had mine apart).

The rub strips on the roof are held on by wellnuts, and often will pull out with a little effort. Be careful to not crack the strips, the plastic shrinks over the metal, and gets extremely brittle. I have a few good ones if you crack any.

While you have the rack off, dig the sealer out of the channels on both sides, and replace it with regular hardware store home roofing sealer. I ran a bead down both sides, and smoothed it with a vinyl glove on my hand. You could also use a screw driver, or squared off popsicle stick that is the same width as the channel. Make sure it is recessed enough for the edges of the roof rack to fit into the channels. Roofing sealer is good for 20 years on a roof, so it is good enough for a car.

You may find some rust on the rear support for the vista glass. I had to fix a number of holes in mine.

Fred Kiehl wrote:

Removing the rivnuts requires drilling them out. If the rivnuts are not rusty, just retighten them with a bolt, nut and washer. Do not use the wellnuts for the rack unless you want a "just cosmetic" one. The wellnuts do not have the strength to hold the rack on the car with anything on it. The rivnuts are metric, and the only place I found the metric rivnuts was on ebay. I think they are 5mm or 6mm (its been a couple of years since I had mine apart).

The rub strips on the roof are held on by wellnuts, and often will pull out with a little effort. Be careful to not crack the strips, the plastic shrinks over the metal, and gets extremely brittle. I have a few good ones if you crack any.

While you have the rack off, dig the sealer out of the channels on both sides, and replace it with regular hardware store home roofing sealer. I ran a bead down both sides, and smoothed it with a vinyl glove on my hand. You could also use a screw driver, or squared off popsicle stick that is the same width as the channel. Make sure it is recessed enough for the edges of the roof rack to fit into the channels. Roofing sealer is good for 20 years on a roof, so it is good enough for a car.

You may find some rust on the rear support for the vista glass. I had to fix a number of holes in mine.

That is super helpful, thanks.  I'm doing it on the Caprice for now so the vista glass won't not be an issue. I'll keep it in mind should I need to do it on the Buick.

Home Hardware carries the Grace products up here.

jayoldschool wrote:

Home Hardware carries the Grace products up here.

The HH website said that product was not available in my area. I'll check with the store directly. I'll be in San Diego next week, so I can just pick some up there if they don't carry it locally.

lol, no "ice" in your area... you lucky SOB.

jasonlachapelle wrote:

Fred Kiehl wrote:

Removing the rivnuts requires drilling them out. If the rivnuts are not rusty, just retighten them with a bolt, nut and washer. Do not use the wellnuts for the rack unless you want a "just cosmetic" one. The wellnuts do not have the strength to hold the rack on the car with anything on it. The rivnuts are metric, and the only place I found the metric rivnuts was on ebay. I think they are 5mm or 6mm (its been a couple of years since I had mine apart).

The rub strips on the roof are held on by wellnuts, and often will pull out with a little effort. Be careful to not crack the strips, the plastic shrinks over the metal, and gets extremely brittle. I have a few good ones if you crack any.

While you have the rack off, dig the sealer out of the channels on both sides, and replace it with regular hardware store home roofing sealer. I ran a bead down both sides, and smoothed it with a vinyl glove on my hand. You could also use a screw driver, or squared off popsicle stick that is the same width as the channel. Make sure it is recessed enough for the edges of the roof rack to fit into the channels. Roofing sealer is good for 20 years on a roof, so it is good enough for a car.

You may find some rust on the rear support for the vista glass. I had to fix a number of holes in mine.

That is super helpful, thanks.  I'm doing it on the Caprice for now so the vista glass won't not be an issue.   I'll keep it in mind should I need to do it on the Buick.

I only have the rub strips for the RM and OCC.