Homedepot up here has an Owens Corning product called Celfort (two densities available) but it is available in 24" widths only. I would like 48". [%-)]
The panels are shiplap butt-edged style so I was wondering those of you who have used these types of panels can tell me if they might fit together well to make a good flat 4X6’ surface that I will need in few sections of the layout?
I will be using cork roadbed on whatever surface I eventually choose anyway.
Presuming this is the blue colored stuff? My HD has not had the pink dense foam in 2 months (they even took the SKU card down from the bin). My store carries only one density of the blue in the 24 x 48.
My observation is the blue is not a rigid as pink. My version had shallow channels pressed in to one side - they use the stuff as a base on stucco jobs here. These channels make the stuff prone to warping along the direction of the depressions.
I just had to be careful how I stored the stuff after painting and before installing on the plywood. I also used a silcione based caulk as the adhesive to keep ot flat.
But depending on what you want to do with a wider sheet, you could joint 2 sections and bond them using the tongue and groove side.
The lack of 4’x8’ sheets always puzzled me, as contractors have been using them as exterior sheathing for well-over 20 years. They are, however, now available to consumers around here (southern Ontario). I suspect that they always were available, too, so if you don’t see them, ask. I’m sure that your dealer can get (or already has) them. I believe that the 2’x8’ sheets are for interior use, with the shiplap-style edges intended for a bead of caulking before the next sheet is installed. This then constitutes a continuous vapour barrier conforming to the building codes, eliminating the use of plastic sheeting for that application.
A couple of points of clarification now that I Googled the Owens Corning product sheets on these.
The Celfort pink comes in several densities C200 to C1000 and thicknesses. Even the 2" C200 is strong enough for a layout, but I will probably spent the extra $3 per sheet and get the firmer 2" C300. (Their product sheets lists the strength stats).
As I corrected above, the lap is ship lap which is intended to give a smooth-butted joint. Does it?
The Celfort only comes in 24" widths, but they have a Celbord Codebord product that comes in 48" widths. I’ve never seen it and the local stores don’t have it on the shelves. I will see if they can bring it in for me or may have to go down to Vancouver to pick some up.
The CodeBord comes by R value. R5 is 1" and R10 is 2". And it appears to be the same kind of thing as the Cefort, manufactured in 4’X8’ and 4’X9’ panels for exterior use. I don’t know how it corresponds to the density ratings of the Celfort, but I imagine it would not be less than the one they call C200.
I am curious why it is not available in the USA…something I have heard in a couple of posts now…or is it just not available in Home Depot.
The lack of 4’x8’ sheets always puzzled me, as contractors have been using them as exterior sheathing for well-over 20 years.
Wayne there’s your answer according to my friends over in Lowes, contractors seem to grab up all of the 4x8 sheets almost as soon as they come off the truck. I am not a bog foam guy at all but I am trying to teach myself the technique because it does seem advantageous in many ways. Besides I like the Lowes brand stuff as it has a light green tint to it rather then that horrid make you puke pink color. What does seem to be in extremely short supply around here is 2" foam. I guess maybe there isn’t much call for it perhaps?
I live in a crappy city and it’s impossible to get a lot of things. However, after wasting time at Home Depot, Lowes, etc. I looked up plastic in the phone book and found a place. They have the blue foam in 4x8 and 4x10 sheets in thicknesses from 1, 2, 4 and 6inches. It’s not terribly expensive even in such huge sizes.
My Lowes here has the green stuff in 4x8, but doesn’t carry pink in any size. They have blue in 2x8 but only 1/2" thick. My HD has pink in 2x8 - and they (Owens-Corning) recently changed the pink stuff to make the manufacturing process more environmentally friendly so now it has a REALLY sick pink shade. It all depends on where you live, and even then it obviously varies. Clealy insulation is needed in my part of the country, so the various stores do stock some, but not a wide variety.
The pink comes in various strengths, mainly rated ont eh compressive strength. So the heavier stuff meant to handle concrete being poured on it will make a stuff structure than the lightweight stuff meant to hold no more than its own weight. HD around here stocks the 250, which is the middle product, and it has proven sturdy enough that I am now buildign my second layout using it.
Around here (Chicago) HoPo, Lowes and Menards only carry extruded in 4X8 sheets. I wish I could find 2X8s so I wouldn’t have to cut the 4X8s in the parking lot to fit into my car.
I joined 3 2ft wide pieces using yellow glue, probably not the best way, and it worked on a small 6’x7’ test layout just fine. I had plywood and table tops underneath for support so I used 1" thick. The tongue and groove kept the adjacent pieces in the same plane. I had no joint failures, but I wasn’t stressing the joints either and they were offset from the plywood/table top joints underneath. I didn’t glue the foam to the plywood.table top either. I used track with built in plastic roadbed and that worked just fine also.
Frankly, I didn’t see any operational improvement over just plywood. It is lighter so for a portable layout that would be a plus if you used the thick stuff by itself. It’s also easy to work with - score and snap.
Thanks for the info, Paul. My first comment on this point is that I want to use the foam to isolate the layout from any shrinkage and movement (gaps) that might occur in the plywood from changes in humitidy in my case (30% to 76%)
I have yet to settle in my mind whether this is a real issue. Several posters have commented that plywood is quite stable because of the advanced glues and number of cross grained layers involved (the more/the thicker the better.
Now I am intrigued by this. I had thought to do the same in some fashion, as I can’t quite see how gluing down the foam to the plywood would be ok if the plywood itself had some movement. Maybe it would.
But, how did you find this system? Did you set the foam within a retaining lip on the plywood or just leave it “float”?. If the foam was only 1" did it lie flat? Did it move over time with the use of the trains running above.
I think you said your setup was just a trial. I suppose it may not have been up long enough to answer my questions, but thanks for sharing your experience.
It was a temporary setup which I took down when I moved. I had it up for about 6 months and set up a double loop test track. I left the foam floating so I could see what would happen.
The only thing restraining the foam was being around a steel support pole in my basement. I cut out an opening for the pole and glued the foam together around it. Other wise there was no clips or anything else to prevent movement. I had no movement.
The foam did lie flat and I had no issues with it not staying flat. I didn’t do anything special to keep it flat.
The test track was not heavily used, but I was running S scale which is heavier than HO or N. Whether or not that makes a difference I don’t know.