Fiberglass Reinforced Plastic - FRP

David Guilbault

David Guilbault

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Oct 10, 2019
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davidguilbault.bandcamp.com
Hi folks. Just beginning to inspect the interior of my newly acquired 1976 Palm Beach. The ceiling is coming down and the upholstered panels are filled with mold and dust. The walnut louvered cabinet doors and wall and drawer veneers are painted white. I'm thinking of replacing a lot of it with Fiberglass Reinforced Plastic. I'd welcome any guidance of how other GMC motorhome owners have used this product. Photos would be stellar. Brand recommendations for the panels and adhesives would be helpful. And any installation tips or travails would be welcome. Here is the manufacturer I am thinking of using (Marlite FRP). Thanks much. Be well. David.
 
I had no idea that they made FRP in those colors and patterns. It gives me some ideas for the bathroom. Thanks for the links.
 
Glue this Hull liner onto coroplast for a very durable ceiling.

www.homedepot.com

Coroplast 48 in. x 96 in. x 0.157 in. (4mm) White Corrugated Twinwall Plastic Sheet (10-Pack) WC4896-10 - The Home Depot

White Corrugated Plastic Cardboard is ideal choice for projects around your home, office and jobsite. Rot, rust and warping resistant.
www.homedepot.com


DAP Weldwood Landau Top & Trim HHR Solvent Type Spray Grade Contact Adhesive 1 Gal: Amazon.com: Industrial & Scientific

DAP Weldwood Landau Top & Trim HHR Solvent Type Spray Grade Contact Adhesive 1 Gal: Amazon.com: Industrial & Scientific
www.amazon.com

http://www.gmcmhphotos.com/.../new.../p24006-after.html
 
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I've had two RVs with hull liner on the ceiling, and it seems to hold a LOT of dust. Both RVs had a lot of staining around the AC vents (from years of airflow), and if a person dared to disturb the ceiling, they would likely end up with dust and fibers in their eyes and lungs. I can't really say how old the hull liner in these RVs was, or how much PO neglect it had seen. Either way, I had little luck cleaning it, and I know FRP would be easier to clean. The downside to FRP would be acoustics though. I'm sure the hull liner wins hands-down when it comes to noise abatement. The question I'm pondering is what I value more. I still haven't decided.
 
I haven't had that trouble in the GMC, but I had to clean a badly stained hull liner ceiling in an SOB the other day. All it took was a cleanser with Oxy clean in it, a small soft brush, then vacuum the moisture out. It came out perfect.
No problemo.
 
Hi folks. While I certainly appreciate all the alternative suggestions on ceilings and walls, I was asking specifically about FRP. I'd like to see how it has been used and hear how it was installed. Perhaps someone else can start a thread on hull liner. I was hoping to keep this one focused on fiberglass reinforced plastic. Thanks for your time and consideration. Kind regards. David.
 
David Guilbault said:
Upholstered panels on the walls behind the sofa/bunk, dinette, and rear settee.
Click to expand...

OK. That's what I thought you meant. I'm not sure if you have seen what is back there from the factory, but if not, it is sprayed-on foam insulation. Some areas it is thick, and some areas it is hardly there. The problem is that there is not much room to add anything unless you use more spray-on insulation like @Justin Brady did with his restoration which basically required removing everything in the coach. You could add insulation without the spray foam, but I think you'd have to strip the existing foam away and then add the insulation. Big job.

This picture is from the area next to the dinette in mine. Your panels fit pretty close to flush with the ribs, so there is very little room to add anything.

Also, I would recommend not getting too hung up on insulation. Yes, it helps. Every bit helps. But on the GMC, a huge amount of heat loss (or gain depending on the time of year) is through the huge amount of single pane windows which there is nothing you can do about. You need to make sure that your furnace and a/c unit(s) are working properly and you should be able to stay warm (or cool). Not much reason to soundproof. They are pretty quiet anyway. And again, you can't soundproof the glass.

IMG_0010.webp
 
Mike Perez said:
OK. That's what I thought you meant. I'm not sure if you have seen what is back there from the factory, but if not, it is sprayed-on foam insulation. Some areas it is thick, and some areas it is hardly there. The problem is that there is not much room to add anything unless you use more spray-on insulation like @Justin Brady did with his restoration which basically required removing everything in the coach. You could add insulation without the spray foam, but I think you'd have to strip the existing foam away and then add the insulation. Big job.

This picture is from the area next to the dinette in mine. Your panels fit pretty close to flush with the ribs, so there is very little room to add anything.

Also, I would recommend not getting too hung up on insulation. Yes, it helps. Every bit helps. But on the GMC, a huge amount of heat loss (or gain depending on the time of year) is through the huge amount of single pane windows which there is nothing you can do about. You need to make sure that your furnace and a/c unit(s) are working properly and you should be able to stay warm (or cool). Not much reason to soundproof. They are pretty quiet anyway. And again, you can't soundproof the glass.

View attachment 1695
Click to expand...

Thanks Mike. Very helpful. I guess what I am really looking for is a new material on which to attach the new upholstery. The old panels are kinda like cardboard and are impregnated with dust and mold. I'm keeping them as templates. I'm hoping I can find a more modern material to which I can attach the new fabric that has some insulating and/or sound deadening properties. I'm new at this, so am really uneducated on building materials. Cheers. David.
 
Yes, the cardboard type headliner and walls panels on mine are completely destroyed. I think the Coroplast (plastic cardboard) that @bdub mentioned above would be a good replacement. It is just over an 1/8th inch thick and would be waterproof. You should be able to glue whatever upholstery you like to it.
 
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