What Are Some Brand Names of Pink Foam For Layout?

[Kisatchie]

I keep telling myself I'm getting closer to building my layout, so I figure it might help if I can mention a brand name or two of pink foam for my contractor to get for me when he starts building my benchwork.

Any suggestions...?


Hmm... I don't have the
slightest idea...

[RBrodzinsky]

Owens-Corning pink foam board is called FOAMULAR
Dow blue foam board is just called Styrofoam Insulation Board

For layout use, whichever is convenient and available to you.

[C855B]

The pink of pink foam is part of the branding for Owens-Corning FOAMULAR®. There are other XPS (extruded polystyrene) insulating foam boards, but they cannot be pink. Dow STYROFOAM™, for instance, is light blue. Then there's a light green brand ( @Ed Kapuscinski uses it, IIRC) I'm not familiar with.

Pink foam comes in several grades, the easiest to find at retail being FOAMULAR 150 and FOAMULAR 250. These correspond to 15 PSI and 25 PSI load strength, respectively. My preference for base benchwork is 250. It's stronger and more resistant to dinging and denting. If you're building scenery with it, it doesn't matter, with 150 available (at retail) in more thicknesses, and for a couple of bucks less than 250. I don't recommend the commonly available Dow (blue) foam for anything structural. Scenery is OK. It's rated at 15 PSI, but I find it to be noticeably less strong than pink "150".

Two things - for telling your contractor what to get for you, let him know you need the pink foam and not the blue. You probably don't have to get super-specific about the brand or anything, he definitely knows what "pink foam" is. If you get the thicker (1.5-2") versions, if there's a choice, you want the square edge and NOT scored. Second thing is to get what you can get easily. All these recommendations are made assuming easy (stocked) availability from his suppliers. You can special order all sorts of strengths and thicknesses in both FOAMULAR and STYROFOAM, but in minimum quantities like 50 to 100 sheets.

Oh... something minor... I've overheard some MRR'ers referring to "purple" foam. No such thing - it was just pink foam where the manufacturer made the pink a little darker. It was still the Owens Corning stuff.

[davefoxx]

I couldn't remember what I used, so I went deep into my thread in the Layout Engineering Forum.  I knew that I bought the 2" x 4' x 8' square-edged sheet of foam at Lowe's, but I had forgotten that it was marked "Lowe's."  Probably rebranded.



DFF

[C855B]

Thanks for the reminder, Dave. That's a custom run for Lowe's, made by Pactiv. Pactiv is not a construction materials company, they are food packaging manufacturer. Can't tell you how Lowe's sucked them into the building materials business, but there's no explaining the big-box purchasing model. I've been using some of the Pactiv-made foam sheathing (1/4"), and now that I know the "heritage", it explains a lot about the working consistency of the material - sort of like using fast-food foam containers as house wrap.   It might be worth my while to pick-up a sheet of the thicker stuff and assess how it compares to the O-C or Dow.

A quick bit of searching found that the light green XPS foam is Kingspan Green Guard. It is available in 25 and 40 PSI versions*. Nobody local to me carries it, so I can't assess its qualities relative to the pink foam. That they offer it in a 40 PSI rating (and have no 15 PSI product) is intriguing.

* - I stand corrected. They have an "insulation board". It meets wall and roof insulation specs, but no PSI rating. I would guess it would be equivalent to 15 PSI, but since 15 PSI doesn't meet code for foundation sheathing, why spec it at all?

[Missaberoad]

 Wow... You have put alot of research into this. +1 for you sir...
I guess i take for granted that I live in a place that understands the value of insulation

Kiz the simplist way to ask for it would be Extruded Styrofoam insulation or SM board.
The extruded is the important part.

[nkalanaga]

I used the blue stuff and haven't had any problems yet.  It's plenty strong enough for my scenery, and I've walked on it, in work boots, while cutting it. 

My advice would be to use whatever is easiest to get, because it all has to be painted or covered, regardless of the color.

[C855B]

I used the blue stuff and haven't had any problems yet.  It's plenty strong enough for my scenery, and I've walked on it, in work boots, while cutting it. 
...

My primary concern with strength is in the ability to use foam board as a primary benchwork structural medium, not as a layer on top of plywood. Concerns there are strength and rigidity between supports. I wouldn't walk on either used that way, but in casual testing of the two major brands, I found 2" O-C (pink) 15 PSI to be significantly more rigid than 2" Dow (one of the blues, Pactiv being the other blue).

I would like to formalize the comparison by quantifying deflection and fracture points. This is data unlikely to be available from the manufacturers because aside from compression ratings (PSI), the foam is simply not intended to be used structurally. A full comparison may be tough because around here, Dow was only carried by Lowe's, and they have changed to stocking the Pactiv-made product. I have no idea yet where I'm going to find Kingspan.

Color only matters for identifying the product.

[C855B]

I just got educated.

Trying to find sources for Green Guard, Pactiv = Kingspan. Drilling down to "about us" at the Green Guard site, there's a press release announcing that Kingspan bought Pactiv's building materials business two years ago. It is apparently still being identified as Pactiv for the Lowe's product line. That must be why I ran into a brick wall at pactiv.com.

[sigh]

Burned by the big-boxes again. As is now typical for the for construction materials market, apparently you have to know when and where you bought the stuff, since they change suppliers (and specs) like underwear.   I'll still try to compare O-C, Dow and Lowe's/Pactiv.

[nkalanaga]

Mike:  Mine doesn't use plywood, but it also isn't the "primary" structural material.  It's laid on wooden joists, just like plywood would be, so is somewhere in between.  I also used two one inch layers over much of the area, so that the top layer could be removed for streams.  It hasn't sagged in over 15 years, although some of the wooden legs have shrunk, and had to be shimmed to bring the layout back to level.  Yes, they had been stored in the layout room for several months, so should have adjusted to the conditions before installation.

[basementcalling]

As long as its not white bead board foam you are fine.

[nkalanaga]

The only thing I used the bead board for was filler under plaster and sand.  No attempt to carve it, just stack it up and build the scenery around it.  Structurally the stuff is useless, but I had several chunks, and it saved scenery materials.

[Ed Kapuscinski]

Dave Foxx has it. That's the stuff I've been using.

I remember the blue stuff possibly being easier to cut though.

Also, I've realized something, you actually don't want the thickest stuff you can get. You're actually much better off building up with thinner, easier to cut, shape and work with stuff.

[nkalanaga]

All of mine was one inch, with thicker layers glued and nailed together.  Spread some construction adhesive on one side, stack the layers, and stick nails through them, at various angles, so they can't all come out the same way.  For more than two layers, just keep repeating the glue, foam, and nails.  In my case, I left most of the nails in.  Unless you plan on poking a lot of holes in your scenery, a little care will put them where they won't be a problem.

The cheapest nails you can find are fine.  If you have a box that simply won't pound in straight, use them here.