Blue or Pink styrofoam insulation for the floor?

[broman]

I am planning on putting styrofoam on the floor of my wheelhouse between two sheets of green treated plywood.

I thought I had read a previous post that mentioned that the blue styrofoam was waterproof compared to the pink. Is that true? Does it matter which one I get?

By the way, I'm following the pics of Kylersk's fishhouse for the construction of my own. Great pics Kylersk !!! They have helped me alot. I might start posting some of my own progress soon.

[Kylersk]

Thanks for the comments..

I personally used white.. I cant remember why though. Probably cost?

[broman]

Thanks, I'll have to check how much the white goes for and it's R-Value compared to the pink and blue.

[hanson]

I really don't think there is a difference between Blue & Pink rigid insulation other than who manufactures it.

Blue is manufactured by Dow Chemical under the Styrofoam name.

Pink is manufactured by Owens Corning under the Foamular name.

They are both a type of insulation called Extruded Polystyrene, which is way different from the stuff "styrofoam" cups, plates, minnow buckets, etc.

R-Value is exactly the same, R-5 per 1".

Both these rigid insulations are good in applications where moisture is present- foundation insulation, fish houses, etc.

Most of the white insulation is cheaper, doesn't like water, and has less R-value.

[efgh]

I would see how dense, or hard the different colors are before I bought any. I know the white is soft and likes to break easy. The blue is pretty darn tought, My thinking is the denser or harder the better because the floor won;t have much give. just my thoughts.

[arcticcat400]

broman if you dont mind me asking where did you get your frame from and how much$$

[broman]

Looks like I'll go pink or blue, but not white.

My cousin custom welded the frame. With the 3/4" green treated decking, new wheels, 2 electric winches, tongue, pins, leaf springs, etc, etc, it cost about $1000 to build.

There is a great deal on one on hsolist (if still available). It's a 7x14 (probably 6.5 x 14) with a v nose front, which makes it a little longer. Check it out. He was only asking $1000. It's brand new from Northern Tool purchased this year. I called him and asked him a few questions about it for curiousitys sake.

[Rainman]

Make sure to check out the load rating on the Northern Tool trailers. The ones I looked at were only rated to 1500 lbs!!! It doesn't take much equipment to weight that much. Just a FYI!!

[hovermn]

Not sure if they changed it, but the other thing I don't like about the Northern trailers is the lack of suspension.

A note about the different foams. For the purposes of insulation, The yellow, pink and blue foams are the same. EPS foam. They are a 2 lb density foam which means a cubic foot weighs 2 lbs. EPS foam has great moisture resistant properties and is probably the best option for preformed foam (4x8 sheets, etc...)

The white bead foam you find at most, if not all home centers is a 0.5 lb density foam. It has almost no crush resistance, absorbs water if exposed (floor) and as mentioned before, doesn't have the R value that the EPS foam has.

Thought it'll cost more, the EPS foam is by far your best option between home store foams. Better R value, superior moisture resistance and overall better for the health of your house.

[Mike L]

I've designed entire homes on extruded poly shallow frost protected foundations (blue or pink). It's the only way to go. The white (expanded poly) is for coffee cups and packing materials.

Hanson was paying attention in Mr Henry's class.

[Kylersk]

Wish this thread was about a year and half earlier! I put pink in walls and now wish I had done the same for the floor. Ah well.

[hanson]

Quote:

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Hanson was paying attention in Mr Henry's class.

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Ha! Dang right I was!

[nytelyter]

my now ten year old house has the white stuff in the floor. and it has served me well. the better stuff was not in the budget at the time. if i were to build a new one today, i would probably rethink a few things and one would be to go with a full two inches of the better stuff, rather than the 3/4 i have now. ... paul

[hovermn]

I forgot to mention that the core material of the hovercraft in my pic is 100% pink foam. When used in a composit structure, it's a great core material. This works with laminating wood or aluminum to it as well. A person could build their house walls by gluing pannels of alum. or wood to the foam and have a stud-less house. Of course, not all men would relish the thought of a "stud-less" house But, it would work great!

[hawkeye43]

What kind of glue do you have to use???

[broman]

Liquid nails should work. I hadn't thought about gluing it down since it will be sandwiched between two layers of plywood, but I suppose I should so it doesn't "bounce".

[hawkeye43]

The reason I asked is some glues that I used melted the styrofoam.

[broman]

I just did a search on the internet and it look like there is a version of the liquid nails that is marked "safe for styrofoam".

[hawkeye43]

Why didn't I think of that, the internet has everything you possible thing of and more. Thanks

[hovermn]

What you're looking for is foam board adhesive. It's safe for styrene foam which includes extruded polystyrene (pink, blue, etc..) and white bead foam. However, I wouldn't use it for lamination construction. See below.

If I end up going down that road, I'm going to use epoxy to laminate the skin to the foam, then vacuum bag each pannel. I would not recommend this route for the novice, but it'll create a bomb proof structure. This route does cost more, but I should never have to worry about the structure delaminating and it should last for years and years if properly taken care of.

Once skin delams from the core material, you're strength is pretty much toast. So, keep that in mind when using the foam board adhesive...

If a person wanted to use polyester or Vinylester resin, you can use urethane foam, the same stuff that has the foil coating (minus the foil) It won't melt with polyester resin like styrene foam will, and the resin is cheaper. The downside is that the foam is usually more expensive than pink and white foam, so you have to figure that into the cost.