FRP and water immersion

[belfert]

I bought some FRP panels 4x10 last fall or winter to use in my bus.  I left them in my enclosed trailer since then and I pulled them out today.  My trailer had sprung a roof leak (Now repaired) so it turns out that water got in between the panels.

Anyhow, a number of the panels are destroyed from being soaked in water for months.  There are places where the top layer simply flaked off and other places where the panels seem to have absorbed water and swelled up.  There are a few panels that seem to be okay.

Should I trust the panels that look okay to really be okay or should I just replace them all with new panels so I don't end up with problems down the road?  I only paid $15 a panel and hopefully I can get more at that price.  (They all looked fine when loaded into the trailer.)

[paulcjhastings]

Water shouldn't do anything to FRP the two parts are glass fiber and cured resin. Unless you have a core material that was affected by the water. Can you post a pic?

[tekebird]

FRP is genrally Fiberglass Reinforced Plywood.

if the enges were not sealed and water intruded the entire thing is suspect.

I'd repalce

[prevost82]

I've never seen any plywood in FRP, I've got it on my bus. Like Paul said it's fiberglass and and cured resin.

[HighTechRedneck]

The FRP I'm more familiar with is Fiberglass Reinforced Plastic.

Apparently there are two types.

[belfert]

Not plywood, just plastic.

I'm wondering how a fiberglass product would be affected by water, but something happened.  I'm wondering if the stuff is not designed to sit in water.  I don't know who made this stuff, but I might call one of the manufacturers to see what they say.

[Kristinsgrandpa]

It could be that expansion from freezing caused it to separate like that.

Ed

[Dallas]

Neither Freezing nor moisture should have affected it,
FRP is used in refrigerated semi trailers with temps that go to -20°F or lower, and moisture from constant washouts, melting ice, wet produce, meat, etc.

The stuff is just about bullet proof, and will handle glancing blows from a fork lift with no problem.

My guess is that you got some from a bad batch. Talk to the place you got it from and see if they will replace it.

Just my 2¢ worth

Dallas

[scanzel]

Personally I would not use anything that has swelled up from water in my living space. Once the water gets inside it will never dry out completely no matter how you try. Plus once it is wet it has the possibility of developing mold internally when exposed to a warm environment.

[RTS/Daytona]

FRP - normally is fiberglass reinforced plastic

This is what corvettes are made of since about the 80's
RTS buses are made of this stuff

It's harder to do body work on because the process leaves
some release agents on the surface - and thruout the material
this makes it hard for ordinary "BONDO FIBERGLASS REPAIR"
to stick to the surface of FRP - There are now a whole bunch
of autobody glues and putties made especially for FRP

IRRC Saturns are made of SMC (sheet molded Composite)
with similar body repair concerns

BUT

I believe that there are FRP BATHROOM PANELS - that are FRP covered MASONITTE
Is that what you have ?? - There available at Lowes and Home Depot

Pet RTS/Daytona

[belfert]

This is just the plain plastic sheet about 1/8" thick.  Nothing but plastic/fiberglass as far as I can tell.

[Hartley]

My "Supreme" truck box body is made of "FRP" which "IS" Fiberglass reinforced Plywood that is about 1/2 Inch thick.

Water can damage the plywood portion and cause de-lamination and warping.

Seems to me that a few years ago Fleetwood was using it to build the
entire one piece side walls for their MH and a number of the "Bounder" series had
to have the entire sides replaced due to a bonding problem.

There are a couple of products that the "FRP" term applies to and I don't think that I ever heard that a corvette is made from "FRP", It is a MOLDED/Laminated/Overlaid (Chopper Gun Sprayed) fiberglass body much like a boat.

So basically if you put fiberglass over plywood you have "FRP" in loose terms.

A technical note: If you do not apply a sealer ( or gel coat ) to fiberglass, Moisture can weep into the core of the material where resins have not enclosed the fibers.
Almost any Fiberglass surface once damaged can degrade rapidly if the surface seal is disrupted whether it be water or other contamination. (sunlight will do it.)

Dave....

[HighTechRedneck]

Just to clear things up (or further muddy them), I did a Google "define:FRP" search.  FRP can refer to either technology, Fiberglass Reinforced Plastic or Fiberglass Reinforced Plywood.

define:FRP

[Hartley]

This is just the plain plastic sheet about 1/8" thick.  Nothing but plastic/fiberglass as far as I can tell.

If it has threads or thread patterns in either side it could be one of the molded fiberglass
sheeting materials like "FILON" which is a weave and epoxy make up.

Most Filon is about 1/16 of an inch thick and normally wouldn't be affected by water or much else since it is a pressure rolled/coated material.

Sounds like you got that stuff like they sell for bathroom walls, Looks like plastic and has a fine fiberglass material embedded in the mix. It will degrade in storage and if it gets wet on the back side since the front is sealed during the texturing process.
I got mine at Lowes and have some that was stored for a while in a damp place and it discolored and warped badly.

[RTS/Daytona]

here's info about FRP and Corvettes

FRP (fiberglass reinforced Plastic) till 1997 - them SMC (sheet molded composite) after 1997)

http://www.americanheritage.com/articles/web/20070307-fiberglass-owens-illinois-owens-corning-r-games-slayter-william-b-stout-scarab-chevrolet-corvette.shtml

http://hubpages.com/hub/How-to-Paint-Fiberglass

http://www.corvetteactioncenter.com/specs/c5/1997/97prod.html

http://www.jtuned.com/content/templates/tune.aspx?articleid=291&zoneid=16

Pete RTS/Daytona