Dow (maker of the blue foam)
has a phone number for locating large dealers:(866) 583-2583 In my experience,
they often will not have a large dealer to whom they sell directly in mild-winter areas, so they refer you to nationwide distributors,
who in turn will refer you to a dealer. Call the dealer names they give you first, before driving.
By the way, Dow has a dizzying variety of blue foam
products. The standard stuff that most people use for model railroading applications is called "Styrofoam Square Edge". Be sure to ask for that specifically. Owens Corning makes the pink foam, which they call Foamular. Their dealer finder is online here.
Did I mention to call first, then drive?
Again, the dealer-finders will list many big-box home supply stores, but in mild-winter areas, most of these do not
have the foam in stock. You know, it might just be a good idea to phone first ...
number of layouts I've been involved with here in the bay area are built with foam, so it's possible to buy it with
a little effort. A number of Pacific Supply locations carry or will order extruded foam, including these:
61 Jordan Street
San Rafael, CA 94901-3918
1675 Mission Rd
S San Francisco, CA 94080
1735 24th St.
They don't stock the foam in S. SF, but as of September 2008 they will order any
amount of the Dow (blue) foam with no minimum.
In the Sacramento area, try:
Service Partners Supply, Inc
(formerly RSA Supply)
8321 Demetre Ave
Sacramento , CA 95828
3000 Mather Field
Rancho Cordova, CA 95670
Phone: (916) 368-3535
Southern California, friends and clients have found the foam at:
Foam Sales and Marketing
1005 West Isabel Street
Burbank, California 91506
As of September 2011, another Southern California supplier
for Dow Foamular is:
FOAM MART INC.
628 North Victory Blvd.
Burbank, CA 91502
The above suppliers
have stocked foam board in the past. Things change -- call first. I can't guarantee that these are the cheapest and there
certainly may be other suppliers to consider -- caveat emptor. (which might be Latin for call first ...)
* By the way, yayhoos on forums will often spout off that the extruded foam is illegal in CA due to cancer concerns
(Prop. 65). This is completely untrue – there just are a lot of folks out there who are jealous of California, I guess.
I have been told that the
foam board is often used in conjunction with radiant heating in floors … this construction method is uncommon in the
milder winter areas of California and may be one reason the foam board is harder to find.