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2 Lb Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boat and Dock Flotation, Soundproofing, Filling Voids, and Insulation (1 Gallon Kit)

Based on 594 reviews
Condition: New
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$75.98
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Availability: In Stock.
Fulfilled by Amazon

Arrives Sunday, Nov 1
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At a glance

Condition
New
Size
1 Gallon Kit
Model
Poly2lbgk
Material
Foam
Coverage
5 cu ft

Features 5

  • 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.
  • This expandable foam is recommended for void filling in nonstructural applications. It can be poured underneath decks and inside cavities where a lightweight flotation foam is needed to provide buoyancy.
  • 2# Density polyurethane flotation Foam 1 Gallon Kit; Consists of 1/2 gallon of Part A and 1/2 gallon of Part B and produces 5 cubic feet.
  • Once fully cured this foam can be laminated over with any type of polyester, epoxy or vinyl ester resin without melting.

Description

Fiberglass Supply Depot was founded in 2005, but our hands-on experience began in the Florida Keys in the 1980s, building boats, dock boxes and custom fiberglass products. We created FSD to give customers more than just materials—we wanted to share the knowledge to use them. Whether you're a professional or doing it yourself, we offer real-world experience to help you choose the right products and get the job done right. Our roots began in the Florida Keys in the 1980s, building boats, dock boxes and custom fiberglass products. In 2005, we turned that experience into Fiberglass Supply Depot. We don't just sell fiberglass supplies—we've actually used them. Our hands-on experience helps customers choose the right materials and understand how to use them. We enjoy helping people tackle projects themselves. From building to repairing and restoring, our goal is to provide the products and knowledge to help get the job done right. Quality materials backed by decades of hands-on experience to help you build, repair and restore with confidence.

Specs 13

Material Foam
Brand Fiberglass Supply Depot
Recommended Uses For Product Soundproofing, Insulation, Flotation, Void Filling
Number of Packs 1
Manufacturer Fiberglass Supply Depot Inc.
Brand Name Fiberglass Supply Depot
Number of Items 2
UPC 819794022859

Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, Nov 1

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


Exactly as advertised
Size: 1 Gallon Kit
Works as it should Shipping was fast and on time. Only issue was with drop off, item was not delivered to correct location making susceptible to theft.
Reviewed in the United States on September 3, 2026 by Brian Anderson

Worked great for outdoor boiler insulation repair
Size: 2 Gallon Kit
I used this to repair my outdoor wood boilers insulation that had previously caught fire. This 2 gallon kit produced a surprisingly large amount of foam that was more than adequate in producing a 6-in thick layer. It appears to be impermeable by water and doing a flame test afterwards resulted in being unable to ignite the dried foam. It was easy to mix with an electric drill and had about a 30 second pour time before foaming. I recommend mixing in small batches. I used red Solo cups to measure and a butter tub to mix which worked quite well. The electric mixer is a must. So far very satisfied with the product ... show more
Reviewed in the United States on October 15, 2026 by Tonyv

Great product
Size: Quart Kit
Great product. Alittle goes a long way.
Reviewed in the United States on September 2, 2026 by josh

Good stuff but lacking labelling.
Size: Quart Kit
It works well but it requires labelling. I found out that the dark stuff is the Isocyanate and the light stuff is the Polyol. And if you want to use a scale to measure by weight, the mix ratio is 100:88, Isocyanate:Polyol. The Isocyanate weighs more than the Polyol. Be sure to mix it with a drill so that you have maximum time to work with it before it starts foaming. It starts to foam about 40ish seconds after you start mixing (in an air temp of 65 degrees F) so you don't really have a lot of time to get it where you want it. Not a problem if you are pouring it, but if you are painting it on something you have to mix it in small batches to account for this. It seems like it takes about 20 minutes to fully expand and dry. If mixed in the proper ratio, the final product is very brittle and rigid, and somewhat fragile. If you add more Polyol, you can make it a bit more flexible and way more durable. I have mixed it up to a ratio of 100:130 by weight (Iso:Poly) and it still expands and dries more or less the same; meaning final product is not sticky and uncured and still takes the same amount of time to dry and expand. For me the best ratio to make it pretty flexible and extremely durable was 100:110 Iso:poly. Yes this means you will have some Iso left over but thats just a small consequence for hacking the system. ... show more
Reviewed in the United States on March 29, 2025 by Toolman

Works as advertised.
Size: 1 Gallon Kit
Works great, I used it to fill cavities in my boat. It expanded as advertised. Clean up is easy with acetone.
Reviewed in the United States on September 20, 2026 by JeepDad78

Worth the money
Size: Quart Kit
Follow the instructions and you'll be happy. Work within the temp parameters and this stuff kicks off and expands like crazy. I use the 3 container method. One each for part And part B. The mix in a 3rd. Stir for about 30 seconds or so then be quick on the pour. I'm happy with the results and more than likely will repurchase in larger quantities to finish up the project. ... show more
Reviewed in the United States on September 1, 2026 by Boat Show

Amazon package handling is poor Product is great
Size: 1 Gallon Kit
arrived a day late and the packaging was crushed so I would say whoever loaded it or possibly the driver handled the package very poorly! The foam product is awesome easy to use works very well I will definitely buy again
Reviewed in the United States on May 7, 2026 by Gary Bryant

2# foam for marine flotation repairs.
Size: 1/2 Gallon Kit
Easy to use. Just make sure you follow directions and mix it well with an inexpensive drill motor paddle. You'll need to work quickly as it hardens fast. I used this to refurbish flotation inside of two 14 year old waterway marker buoys.
Reviewed in the United States on June 10, 2026 by Dusty
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