Model A Roof Insulation

[JohnB15632]

I would like your opinion positive or negative about insulating the roof on my Model A with 1/2" Foil back styrofoam in between the wood ribs?

Thank you,

[Tom Wesenberg]

It should help with temp and noise, but I wonder if it should have been on top of the wood bows?

[100IH]

Yes, you don't want it falling down onto the headliner in clumps.

[1930artdeco]

Dad used house insulation and it works great for temps and sound. When I redo it I will probably use something else though.

Mike

[duke36]

Suggest not insulating with fibreglass or other synthetic materials. These products can entrap moisture and foam can disintegrate over time especially with a black vinyl heat absorbing roof. It's suggested to allow the roof materials to breathe as much as possible so as to not allow condensation buildup under or above (depending on climate and temperature conditions) the foil membrane.
An alternate system which some prefer is to remove the chicken wire and install 1/8" 'masonite' type board overlayed by indoor/outdoor carpet and then the vinyl roof covering. This gives a stable roof and a little more insulating capacity when used with a cotton or other natural fiber based breathable headliner. The contact adhesives can act as membranes eliminating the condensation collection issue. The downside can be replacing the vinyl as it's glued to the carpet substrate.

[jrelliott]

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I used the foil backed insulation on the inside. I did not use the chicken wire, but used 1/8" Baltic birch instead of the chicken wire and screwed it down with #4 1/2" long flat head screws counter sunk. This gave a good surface on the inside to a spray 3M adhesive to attach the insulation. Then put the headliner in. The top surface of the Baltic birch was coated with 3 coats of Spar varnish. Never have to worry about the wood rotting if it ever gets wet.

[NCRebel]

I agree with a breathable material for an insulator. The heat from inside of the vehicle will rise to the roof and be trapped in the car thus holding moisture as it condensates on the cold exterior of the car. Airflow of any kind will displace that moisture.

[cpf240]

What about rock wool insulation?

[Big hammer]

1/2 in foil backed foam would be way to thick! There are better ways to insulate!

[ed thibodeau]

I have had the Styrofoam between the ribs for twenty years and no problem with moisture but you should glue them in because they will squeak with the motion and twisting of the body when traveling. I used 1" thick because that is the thickness of the ribs.

[JohnB15632]

OK Guys

Let's make this the end of the post. I will remove the styrofoam and go forth.

Thank you for your advise.

John

[desotoguy]

Whatever you use, if worried about it falling down on the upholstery, use the insulation wires from a builders supply cut to the proper length and inserted between the bows. This is how batt insulation is held between the joist under your house, if you have crawl space.

[JohnB15632]

Since this is continuing, would polypropylene sheet, 1/8" thick work between the wood roof ribs?

Thanks,

[Jim Baskin III Pa.]

I used Dynamat on the whole interior, including the roof of my 30 Tudor.That was 10yrs ago and have had no problems with moisture or otherwise.

Many a Model A men have commented how quiet the car is.