Styrofoam ceiling

Nov 05, 2007 35 Replies

Styrofoam is usually 1.0 pounds per cubic foot. It has a flame spread rating that is considered too high to be left uncovered. It will not burn unless the flame is supported by other material, but it will burn under those conditions.

The moldings you see are made from recycled styrene material and are a much higher density, thus a lower flame spread. They are usually used in lesser amounts also. Please, they are different materials.

You asked for advice. I've been working with foam plastics for 37 years (packaging, building products, aircraft products, pharmaceutical products) so I have some idea what I'm talking about. I'd not do what you propose in my house and I advise against doing it in yours. No recessed lighting in foam.

That would be a big no no. It would be illegal and a serious danger to anyone in the home. I also believe it would be quite ugly.

Thanks for your post. I've got two types of styrofoam (polystyrene). A bag white decoration sheets clearly and sold as intented to be glued to the ceiling. They won't support any weight.

And then I've got blue much better quality looking (denser) larger sheets. At the depot they said it can be painted. My son uses them for miniature carvings. He carves it with chisel and hot wire.

Sir,

What part of the word "RECESSED" do you not understand? How in the f__k are you going to install recessed lights in a concrete ceiling when you only install 1 1/2 inches of foam? Thats barely deep enough for an electrical box. Unless you bust a hole in the concrete, this simply is not going to work. Either start over your plans from scratch, or get rid of the recessed lights and use surface mounted lights which will work well since the box will be close to level with the foam surface. Of course, you are probably violating building codes and in a fire you'd die in seconds from the burning foam. Why not just glue on furring strips and add ceiling tiles? Either way, forget the RECESSED lights. WAKE UP..... this is NOT going to work.....

Unless the styrofoam was made with a chemical additive, and most likely it wasn't, it isn't considered flame retardant. UL once classified it as "self extinguishing", meaning the material will quit burning if the source of flame is removed , but UL was heavily criticized for giving that classification to styrofoam, and apparently the "self extinguishing" label was based on a test where the material sat horizontally in a wind tunnel and set on fire.

BTW, the term "fire resistant" can apply to materials that burn fairly easily, including fire wood. :(

You're referring to all kindling I've ever found around a camp site for the past 35 years. :-)

According to Edwin Pawlowski :

While polystyrene is indeed somewhat less toxic than some other types of foams, how toxic it actually is is highly variable depending on conditions. Eg: low O2 will result in incomplete burn.

The initial combustion products are styrene and carbon monoxide. Neither of which are good for you.

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May I ask why you are considering a low-profile suspended ceiling with fluorescent lights? Seems like it would give you the same result with quite a bit less hassle.

Oops. Should be "no considering"...

Good idea in terms of installation. Bad idea in terms of ugly light (a generalization that's generally true).

Like the styrofoam wouldn't be? I didn't know he was going for aesthetics. I was thinking about the ability to recess it and keep a low profile.

The self extinguishing term was used until some time in the mid 1970's when the lawyer changed it to "modified" material. They add bromides for the fire retardant. The reason for the change was a lawsuit where some idiot burned his house down and claimed he thought hte foam would put it out or some such nonsense.

In practice, the modified material will go out if you remove the source of ignition. When surrounded by other flammable materials, the flames from those materials supports the burning of the foam, thus the need for covering. An exception to this is drop out or melt away ceiling tiles used below sprinkler systems. They are usually 1/2" thick.

Another clarification here. Styrofoam is the registered trade name of Dow Chemical's extruded polystyrene board, colored blue. There are other brands of extruded board in different colors. Then there is the expanded polystyrene board that is wire cut from billets. Often called "bead board" since it is made of molded beads of the material. Any material used in construction must be made of the modified material. When used in packaging or cooler, regular material is usually used and is more likely to burn and keep burning once started.

That's the missing link here. It **seems** he's using something he found laying around, without having any idea if it's safe to use indoors. Read ALL the messages in the discussion. The guy has a deluxe reading comprehension problem.

Dittos. You would not carpet a ceiling, for example, where carpet on floor is not a problem, but on ceiling - whoosh ;)

Frank

Could he has mis-named the stuff and not mean actual styrofoam but some other material sold for such use in ceilings?

"JoeSpareBedroom" wrote in news:C8GXi.20167$ snipped-for-privacy@news02.roc.ny:

Yea, imagine knocking off a piece in the room and the equivalent of a melting plastic army man landing on the backside of your nads.

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