Rigid-foam insulation: Pink stuff or blue stuff?


Chevron_GATX

Chevron_GATX

Member
I see most here using the pink stuff, but for whatever reason the only Home Depots which carry pink stuff is further away. The blue stuff is available much closer. Why do you pick pink over blue?

• Owens Corning FOAMULAR
• R-Tech INSULFOAM

Also, the Owens Corning product is "scored." Is this helpful? What's the best way to make a clean cut on 2" foam? Would a fine-kerf blade on a 7" circular saw do it?
 
Wait, isn't that R-Tech product that crappy styrofoam stuff (expanded polystyrene, or, EPS)? Whereas, the Owens Corning product is extruded polystyrene (XPS)?
 
You want the extruded polystyrene insulation foam board, and I know that both Corning and Dow make it. One was pink, the other blue. What you don't want is the beaded Styrofoam....the kind you find blowing around in chunks at the beach because it doesn't stand up. It's also the packaging you get inside TV boxes and such. The insulation foam board can be scored with a carpet cutter or utility knife and snapped apart cleanly over an edge. Not so the Styrofoam.
 
Because the original Pink Panther movies with Peter Sellers were hilarious!:D
[YOUTUBE]omek-g6_LAQ[/YOUTUBE]
 
My retired architect friend gave me the Dow blue Styrofoam & it's working just fine for me. Have read module clubs talking about using both the blue & pink kind.
 
Blue and pink work equally well. In my area, only the pink foam is available. I kind of prefer the blue myself because a spare piece can always be used as a sky color backdrop for photographs. As for the material itself, there is no real difference for our construction purposes. However, some brands of foam have a matt clear film covering it that can interfere with hot wire cutting and with gluing pieces together. Try tearing off a small corner to make sure there isn't a film covering the surface. If there is, you'll need to peel that film off before you use it.
 
Last edited by a moderator:
Both colors are available in my area. I have used both and see no advantage to one over the other.

You can see in the photo below that I used both colors of foam on the same layout -- 3/4-inch blue for sub-roadbed and 2-inch pink for risers.

- Jeff

grades700.jpg
 
Blue, if it's Dow, is basically same as pink (Owens Corning). Now, to get really confusing... the blue stuff by Dow is actually trademarked Styrofoam. And it is okay to use if it is extruded polystyrene. We all call the crappy beaded white stuff "styrofoam," but technically that is not the correct name. In fact Dow has long run ads in the trade press warning especially journalist not to use the word styrofoam unless it was a reference to their particular product. But as to your original question, pink or blue is just fine as long as it is the extruded, not expanded, variety.

Sent from my SAMSUNG-SM-G930A using Tapatalk
 
Hey, thanks for everyone's replies! Yeah, I figured that both the pink and blue were essentially the same stuff, extruded polystyrene (XPS). The weird thing is, Home Depot only sells the pink stuff, and for some reason, only a few Home Depots in the Los Angeles area carry it (the nearest stock is all the way in Burbank). By the way, is floral foam (trade name, "Oasis") an adequate substitute for XPS? (I looked it up, and it's made of carbon black and formaldehyde).
 
The availability of extruded foam is a regional in nature. It is used for home insulation, so you are more likely to find it in areas where the climate is cooler and less likely in warmer places like California.

Here in Ohio, most home centers carry both colors in several different thicknesses.

If you perform a Google search for floral foam model railroad you'll find that some folks are using it. It would not be my choice, but apparently it works.

- Jeff
 
You must log in or register to reply here.



Back
Top