--- product_id: 423761959 title: "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)" brand: "fiberglass supply depot" price: "£104.20" currency: GBP in_stock: true reviews_count: 5 category: "Fiberglass Supply Depot" url: https://www.desertcart.co.uk/products/423761959-2-lb-density-expanding-pour-foam-2-part-polyurethane-closed store_origin: GB region: United Kingdom --- # 5 min full expansion time 2 lb density for optimal buoyancy 95-98% closed cell water resistance 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) **Brand:** fiberglass supply depot **Price:** £104.20 **Availability:** ✅ In Stock ## Summary > 🚤 Float Above the Rest with Foam That Works as Hard as You Do! ## Quick Answers - **What is this?** 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) by fiberglass supply depot - **How much does it cost?** £104.20 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.co.uk](https://www.desertcart.co.uk/products/423761959-2-lb-density-expanding-pour-foam-2-part-polyurethane-closed) ## Best For - fiberglass supply depot enthusiasts ## Why This Product - Trusted fiberglass supply depot brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Rapid 5-Minute Cure:** Fast foaming and curing to keep your projects on schedule - • **Precision 2-Part Mix:** Equal parts A & B for flawless expansion every time - • **Versatile Application:** Ideal for soundproofing, insulation, void filling, and structural buoyancy - • **Superior Flotation Power:** Supports 480-600 lbs/gal buoyancy—perfect for boats & docks - • **Water-Resistant Closed Cells:** Nearly impermeable foam that resists water absorption and decay ## Overview This 2 lb density, 2-part polyurethane closed cell foam kit delivers 5 cubic feet of high-performance expanding foam designed for flotation, soundproofing, insulation, and void filling. Tested to U.S. Coast Guard standards, it offers rapid 5-minute expansion, exceptional water resistance (95-98% closed cells), and compatibility with polyester, epoxy, or vinyl ester resins—making it the go-to solution for professional-grade marine and construction projects. ## Description 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) : desertcart.co.uk: DIY & Tools Review: I wanted to try this foam for setting fence posts instead of buying the stuff at the home improvement stores. Compared to the Home Improvement store post foam this foam is a little lighter weight and not as hard but still seems to do the job and it is, or was, quite a bit cheaper than the store foam. I don’t know if I would recommend it for building a deck but a residential fence would be fine. Mixing is easy enough, I got a couple silicone measuring/mixing cups and a silicone stirring sticks so I could reuse them once the foam hardened. Review: Easy to pour ## Features - Causes skin irritation. - Harmful if inhaled. - May cause allergy or asthma symptoms or breathing difficulties if inhaled. - May cause an allergic skin reaction. - May cause damage to organs through prolonged or repeated exposure. - May cause respiratory irritation. - 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. - 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 ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B08RP8DNDB | | Best Sellers Rank | 411,078 in DIY & Tools ( See Top 100 in DIY & Tools ) 362 in Expanding Foams | | Brand | Fiberglass Supply Depot | | Customer Reviews | 4.6 4.6 out of 5 stars (274) | | Manufacturer | Fiberglass Supply Depot Inc. | | Material | Polyurethane | | Model Number | Poly2lbgk | | Part Number | Poly2lbgk | | UPC | 819794022859 | ## Product Details - **Brand:** Fiberglass Supply Depot - **Manufacturer:** Fiberglass Supply Depot Inc. - **Material:** Polyurethane - **Number of Packs:** 2 - **Number of items:** 2 ## Images ![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) - Image 1](https://m.media-amazon.com/images/I/81ib1TuKHEL.jpg) ![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) - Image 2](https://m.media-amazon.com/images/I/8189VtbwU2L.jpg) ![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) - Image 3](https://m.media-amazon.com/images/I/71Gbm9XW+IL.jpg) ![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) - Image 4](https://m.media-amazon.com/images/I/71Jn4WV0S0L.jpg) ![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) - Image 5](https://m.media-amazon.com/images/I/81mbAHsaZfL.jpg) ## Questions & Answers **Q: Can the Part B liquid be colored so that the expanded foam will be a color other than beige?** A: unknown It can be painted. **Q: can this be cut with hot wire ?** A: Yes, but it is high density. It will not cut as easily as Styrofoam **Q: Does this require moisture to cure?** A: This will not cure with moisture present. **Q: whats the difference between 2#,4# & 6#? is the polyurethane hydrophobic or hydrophilic?** A: To clarify, each density of foam has a different expansion rate, so they are all used for different applications. Please refer to the reference chart of each listing for details regarding expansion. This material is hydrophobic. -FSD ## Customer Reviews ### ⭐⭐⭐⭐⭐ Review *by E***D on 20 October 2025* I wanted to try this foam for setting fence posts instead of buying the stuff at the home improvement stores. Compared to the Home Improvement store post foam this foam is a little lighter weight and not as hard but still seems to do the job and it is, or was, quite a bit cheaper than the store foam. I don’t know if I would recommend it for building a deck but a residential fence would be fine. Mixing is easy enough, I got a couple silicone measuring/mixing cups and a silicone stirring sticks so I could reuse them once the foam hardened. ### ⭐⭐⭐⭐⭐ Review *by B***N on 13 April 2025* Easy to pour ### ⭐⭐⭐⭐⭐ Review *by J***H on 8 March 2025* Magnificent. I had a sewer vent inside of a wall cavity that was leaking sewer gas inside the concrete slab. Faced with $5000 of work, I instead mixed a cup of each of these and poured it into the cavity. The closed-cell foam blocks sewer gas better than concrete. It worked beautifully! The next day, I decided to fix my tippy mailbox. Instead of mixing a bunch of concrete, I poured in a half-cup of this. Job done. The only thing unclear is that you have to add B to A, not the other way around. (Or maybe it is the other way around. Read the instructions.) The only thing that's annoying is that A and B have different densities so I have to mix it by volume, not weight. I'm probably too careful with that. ## Frequently Bought Together - 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) - Custom Shop Paint Mixing Cups Plastic Measuring Cup Epoxy Resin, Disposable or Reusable, 32-Ounce Quart - Pack of 12 - Graduated, Mixing Ratios, Automotive Painting Acrylic Art Crafts Kitchen - TCP Global Wood Paint Mixing Sticks - 50 Pack - Automotive, Crafts, Airbrush, Art --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.co.uk/products/423761959-2-lb-density-expanding-pour-foam-2-part-polyurethane-closed](https://www.desertcart.co.uk/products/423761959-2-lb-density-expanding-pour-foam-2-part-polyurethane-closed) --- *Product available on Desertcart United Kingdom* *Store origin: GB* *Last updated: 2026-05-24*