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Fiberglass Supply Depot 6LB Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (Quart Kit)

  • Based on 40 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Fiberglass Supply Depot

Arrives May 6 – May 10
Order within 10 hours and 57 minutes
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Features

  • Flotation Foam is a polyurethane 2-part foam that, when mixed in equal parts and poured in place this foam will soundproof, insulate, or provide extra buoyancy.
  • 6LB. Density polyurethane flotation Foam 1 Quart Kit; Consists of 1 Pint of Part A and 1 Pint of Part B and produces 0.375 cubic feet.
  • Once fully cured this foam can be laminated over with any type of polyester, epoxy or vinyl ester resin without melting.
  • The 6LB density also works well in floating decoy or taxidermy applications as well as many other sculpting, casting, carving and other filling applications
  • All expansion rates and times given are temperature critical. Temperatures below 75 F will lower the expansion rate therefore requiring more foam. Ideal working temperature is 75 to 80 F or above. Accurate measuring of these products is extremely critical. Working time before foaming: approx. 45 seconds Time before full expansion: approx. 5 minutes

Brand: Fiberglass Supply Depot


Specific Uses For Product: Flooring, Repair, Casting, Wall Repair, Furniture, Woodworking, Wood


Material: Foam,Resin


Item Form: Liquid


Special Feature: Soundproofing, insulation, buoyancy, resin lamination compatibility


Specific Uses For Product: Flooring, Repair, Casting, Wall Repair, Furniture, Woodworking, Wood


Compatible Material: Vinyl


Item Form: Liquid


Other Special Features of the Product: Soundproofing, insulation, buoyancy, resin lamination compatibility


Container Type: Can


Viscosity: Low


Full Cure Time: 5 Minutes


Water Resistance Level: Not Water Resistant


Item Package Quantity: 1


Volume: 1 Quarts


Brand Name: Fiberglass Supply Depot


Model: 76


Global Trade Identification Number: 76


Manufacturer: Fiberglass Supply Depot Inc.


Included Components: 6lb poly foam


Unit Count: 32.0 Fluid Ounces


Material Type: Foam,Resin


Color: Clear/Transparent


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: May 6 – May 10

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • Excellent Closed Cell Foam for Small Projects
This worked well to fill a small void in a fiberglass boat step project I was working on. I am not sure how waterproof it would have been because I encapsulated it with epoxy before covering it with glass and Coosa board. One thing I had trouble with was figuring out how much to mix for the size of void. That information was provided but I way over estimated how much was needed. It was easy enough to cut off the excess with a hack saw. The image attached is "after" I made the adjustment to closer to the right amount. Making that calculation easier for smaller quantities would be nice. Along those lines, markers on the bottles for smaller batches would be very helpful. Nice product though. ... show more
Reviewed in the United States on December 23, 2025 by Hube

  • Very good - just what I needed
The media could not be loaded. This saved me having to rip out and re-mortar a tub. First time mortar bed for fiberglass acrylic tub and the mortar shrank leaving voids. This fills the voids perfectly, it’s incredibly solid now. In case you’re wondering as I was, this will go through a tube to get it exactly where you need it. I was afraid it’d expand in tube before exiting. I had it mixed and poured in funnel though within 20sec. Void and tube in vid both 5/8 in. ... show more
Reviewed in the United States on July 17, 2024 by bpa78

  • 6lb foam
As described. Easy to mix, drys quickly.
Reviewed in the United States on February 20, 2024 by tony

  • floatation foam for a canoe
I underestimated how much I would need will have to get more easy to use
Reviewed in the United States on August 28, 2023 by Russ

  • Amazing stuff
This says 45 sec working time it very well means it. Mix fast and get it were you need it. Gets very hot in its reaction.
Reviewed in the United States on January 22, 2023 by jayOz

  • Waste of money!
This is the worst 2 part foam I’ve ever bought. It didn’t hardly expand at all. It had clumps all in one of the bottles. We waited to use when the temperature was optimal. This was a complete waste of money.
Reviewed in the United States on March 28, 2024 by Daniel

  • Doesn’t expand very much
Doesn’t expand very much I have been using a 2 lb foam from a different company I have set amounts I use but now with this I have to use twice as much to fill the same space granted this stuff is very dense
Reviewed in the United States on August 7, 2023 by Edward huff

  • Product change?
Ive used prior and this time it did not “grow”
Reviewed in the United States on April 15, 2023 by MamaT

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