Question About Inner Panel Removal

[ohnomrbill]

Greetings,

We're planning on removing the inner panels (roof and ceiling) to re-insulate our 94 Bird with spray foam as many folks on the forum have recommended. But I had a question that I didn't really see covered in the posts I read, or at least not conclusively answered.

Wouldn't removing all the riveted panels weaken the overall bus body structure and make it a lot more prone to flexing?? Or am I just overthinking this? We are planning on using wood paneling on the roof and part of the sides.

Any thoughts/opinions from y'all are welcome.

Thanks!

Bill

[Scooternj]

Originally Posted by ohnomrbill

Wouldn't removing all the riveted panels weaken the overall bus body structure and make it a lot more prone to flexing??

Absolutely, positively not. If anything, the spray foam insulation will improve structural integrity over the interior panels.

[Tango]

Still varying opinions on this one. Once again I will relay what a retired Blue Bird engineer over in Douglassville, Georgia advised me when I was about to raise the roof on my 40' All American...

According to him, the internal sheet metal played a critical role in the integrity of the overall structure by boxing in the roof ribs.

I don't have an engineering degree...but I will listen to folks that do at times.

Properly adding foam absolutely helps rigidize the skin and provides many benefits, but I cannot see it tying the structure together the way a mechanical connection between ribs will.

Just my 2 cents as heard from an old codger.

[ohnomrbill]

Riveted panels add a lot of strength to an airframe, so it would make sense that the same principle applies here - of course my bus is not going to be going 200+ mph, which works in my favor. I guess if the foam is really helping and obviously a lot of people are doing this with no problems, I shouldn't worry too much about it.

Thanks guys for your replies.

[charles_m]

I can attest from personal experience you will be fine. I've done a few thousand miles on a 20" raise and foam insulated walls with new strapping.

If you replace the skin with strapping and new walls, you'll recoup some rigidity, but you will also gain a lot of rigidity from the spray foam. I don't think you'll go too wrong here.


Your bus will feel amazing with that new insulation!

[ohnomrbill]

Awesome ... less worried now. Thanks!