Hello everyone, 1st post here, here’s my question. I need to bond some plywood to 2″ thick “pink” rigid insulation, brand-name- foamular 250(dow chem), its the stuff normally used around foundations, etc. It is the horizontal “platform” at the base of a bay window. On the inner edge-towards kitchen i can screw the plywood to the short wall that supports the inner side. The rest going towards the windows is the foam on top of aluminum siding- no framing. The little framing there is, is under windows and can’t be accessed. I know its strange, its a mobile home-“yikes”, and it may be hard to picture from my description, but the bottom line is I need to bond plywood to the foam without fasteners.
I have experimented with different construction adhesives. PL premium polyurethane const adhesive, which is supposed to bond to foam, doesnt work, just peels off like tape. Titebond proffesional const. adhesive melts the foam. so does contact cement. The only thing i’ve found that actually sticks to it, along with everything else in sight, is “great stuff” expanding foam insulation( in a can) which i’ll probably have to use, and drill holes in the plywood to allow the extra to escape. I dont look foward to that because it will get all over whatever i’m weighting down the ply wood with and probably glue that down too. Anybody know of a product that will really bond to the rigid foam? Thanks, Sunnyboy
Replies
spray foam from a can is the ideal solution that I use for those cases. I regularly build the hatch covers for attic access with a mini SIP sandwich of ply/foam/sheetrock.
there are versions that are actually made for use as a glue rather than insulation with less expander in the mix.
Gorilla glue is also a polyurethene glue that will work for this, but will still foam.
The only tube glue I know of for this foam is PL300. Somebody else mentioned another brand made for foam here once, but I don't remember it. I'm thinking a locktite???
Welcome to the
Taunton University of Knowledge FHB Campus at Breaktime.
where ...
Excellence is its own reward!
Yes, Loctite makes one specifically for foamboard.'Man who say it cannot be done should not interrupt man doing it' ~ Chinese proverb
View Image
Thanks for the tips, Piffin and FatRoman, i may grab a can of the less expanding foam or look at the PL300 and maybe test it first and see. I'm all out of gorilla glue so havent tested it. thanks again, have a great day
If you get a foam gun, you can greatly contol the amount and placement of a bead of foam - you can lay a bead 1/8" with it instead of blasting it into open spaces. You can also use the glue type foams that only faom up a little, these are commonly used for subfloor aplication, but work great for sheetrock too.
Tu stultus esRebuilding my home in Cypress, CAAlso a CRX fanatic!
Look, just send me to my drawer. This whole talking-to-you thing is like double punishment.
These glue type foams you're talking about, they come in standard tubes like construction adhesive? A foam gun would be nice, what do you load that with, the stuff in the can? or something else? Anyway, appreciate the comeback, sunnyboy
PL300 in a caulk tube....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
"Some days it's just not worth chewing through the restraints"
when you buy the disposable cans of spray foam it is the DIY solution at exagerated prices.A foam gun will run you $20 to $80 and the canister of foam will screw onto it. I can get about five different types ( densities and expansion rates) of foam.Each cannister will provide about ten time3s as much foam as I get in the disposanble cans for only about 3X the price. And about 20X as much glue as in a tube of 10.5 oz caulk You do have to clean the gun occasionally tho, and it is not worth the investment if you only use 2-3 disposable cans a year.Something to keep in mind - some of the disposable ones are now the latex low VOC foam, but I don't have much confidence that will work as well as urethene foam for a glue.
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
You're right about the latex foam- no good- tried it. Its good to know about the foam guns, though i really dont have the need right now or the money. I just found a half a tube of loctite's power grab, testing it now.
I'm gonna pick up some gorilla glue or a similar product, maybe one less foaming, i need to have some around anyway, and see what it does. I like the idea of having a continuous film, rather than beads, so there's no air gaps. I'm just remembering now, don't they use roofing cement or something like it to coat a foundation on the outside and then stick the foamboard on? I've seen it out there for quite awhile before the backfilling gets done, and seems to stay in place. just a thought.
I'll let you know the final outcome and try to post some pictures of the finished job. Lots of good info from everybody, i think i'm hooked on "breaktime" now. Talk to you all later.
Are the walls smooth enough to get a continuous film ? You might try adhesive for sheet vinyl. I think that it will bond to the foam but not disolve it like most construction adhesives will. You could try water based contact cement too.
These are just ideas that might work. I have use PL 300 and know that it works.
Just exchanged 2 tubes of pl polyuethane constr. adhesive for a can of minimum expanding foam insulation and a tube of pl300 since it seems to be popular. I know the spray foam will stick to both the plywood and the rigid foam, but if the pl 300 sticks well also, i'll use that. The bay window area gets alot of temperature extremes and there has been a condensation problem though that may be fixed since its better insulated and sealed now, but either way i need something that really sticks. Cant use any mechanical fasteners which is what i would do 9 times out of 10, and then you really dont know how well these construction adhesives adhere. half the time it just helps to distribute a load or fill small gaps, but if say you nail down a subfloor, you never know if the construction adhesive is really gluing the thing (unless of course you have the fun of tearing something apart that has seen better days) Gonna test first and then proceed. have a good one sunnyboy
All of what Piffin said.
http://www.amazon.com/Great-Stuff-Pro-Gun-14/dp/B0002YOMJE
View Image
This is the foam gun I like, it's cheap and you can easily take it apart.
I find the foam lasts for months attached to the guns. I haven't had one seal shut yet.
Tu stultus esRebuilding my home in Cypress, CAAlso a CRX fanatic!
Look, just send me to my drawer. This whole talking-to-you thing is like double punishment.
Just bought 5 tubes of PL300 foam board adhesive at Home Despot this afternoon.Check by the insulation goodies.
I have had good luck with Liquid Nails "heavy Duty" construction adhesive. Seems to work as well as PL 300, much less expensive. Easy to gun out in the cold.
http://www.duspec.com/DuSpec2/product/ProductDocumentSearchController.htm?documentFormat=pdf&systemSetId=70&productCode=LN-901&documentType=datasheet