Homemade SIPS?????

Carol K · #1 04/20/06, 05:14 PM

I am able to get my hands on styrofoam (?) blocks that are maybe 18x10x10. I hate to see them go to waste and was wondering If I could make my own SIPS? Do you think if I sandwiched them between 2 sheets of OSB, they would be strong enough to hold a roof? Was thinking of maybe a small barn.

Carol K

Obser · #2 04/20/06, 06:09 PM

Carol, SIPS should have some lumber framing inside, at least along the edges. That can act as posts and (somewhat) like beams. The OSB and foam will hold some weight too, so it seems logical do make the "sandwich" you propose -- particularly for an outbuilding.

I am not an expert on these matters but have been involved in a SIP construction project.

Carol K · #3 04/21/06, 06:19 PM

I think they just have a header and a footer(?) which I could easily do. Anyone know which glue to use, I have read that some glues just eat away at polystyrene.

Carol K

Obser · #4 04/21/06, 06:45 PM

Carol, a water-based adhesive like Elmer's is compatible with most foam -- though I don’t know specifically which would be best to use in your application.

Don't use solvent-based adhesives or paint or they will destroy the foam, as you say (like gasoline does to a Styrofoam cup). Water-based paints are generally okay to use.

Also, the SIPs we worked with were framed all the way around with 2x4s or 2x6s -- both edges and both ends. That is how they were fastened to one another. There may have been some framing inside the panels, I don't know (or can't remember).

"Raceways" were left for electric wire, and outlet holes were cut. Window and door openings were cut and fully framed.

Obser · #5 04/21/06, 07:05 PM

Another bit of information you might find useful: Styrofoam can be easily and uniformly sliced with a hot wire, which is nothing more than resistance wire connected to a power source (for instance, a battery or power supply).

If you wanted to slice the foam blocks to make them more useful, you could rig a hot wire the appropriate distance above a table surface and push the block through. It would take a little research and some (minimal) equipment to do this, but might increase the usefulness of the foam blocks.

Some commercial operations buy foam blocks that are 4' x 4' x 8' or bigger, then use a stack of hot wires to slice the block into whatever thickness is desired.

LagoVistaFarm · #6 04/21/06, 09:19 PM

I think knowing exactely what the material is will help. If they can be bonded with isocyanates there will be much more structural strength capacity. If they are really styrofoam think of the panels as wall/insulating units and have posts for the roof support. I've only built foam core structures in earthquake country so I'm not sure of the snow loads.

I assume you won't need a building permit for the barn.

IDgoats · #7 04/21/06, 10:36 PM

My neighbors, are just finishing up an ice block house. which has verticle and horizontal runs with built in plastic tees. and the construction company that put it up used adhesive foam to glue it to the footings and to it self. as far as cutting it they used a sawzal. to cut windows after it was glued up they used a chain saw. they gave me they scrap block and i cut it in half so i had 21/2 inch thick slaps then used it to insulate my goat barn, then used adhesive foam to glue in place and seal cracks it really kept my barn warm this winter. so good luck and hope this helps you if you could post picture of block might be ale to help more.

dan

Freeholder · #8 04/21/06, 10:57 PM

I got a bunch of blocks like that (thrown away behind one of the local feed stores -- my mom is a scavenger!). I've been using them to keep stuff up out of the mud -- and cursing under my breath whenever one of them goes flying all over the neighborhood in our frequent high winds. I retrieved seven of them a few days ago! If you have poultry, you'll need to protect your supply of blocks from them. They eat styrofoam -- chickens, ducks, and geese!

Kathleen

MrPG · #9 04/21/06, 11:01 PM

Wondering if "Liquid Nails" adhesive would work with these kind of styro blocks?

stanb999 · #10 04/22/06, 03:16 AM

Quote:

Originally Posted by MrPG

Wondering if "Liquid Nails" adhesive would work with these kind of styro blocks?

That's like using 60D nails for lewan. It's way overkill. The styrofoam is basically weak. Use some cheap clear silicone. The stuff thats like 1 buck a tube. That will hold it together very well to the point you will rip it apart to get it off.