--- product_id: 692715743 title: "Fiberglass Supply Depot 4 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: "€ 629.75" currency: EUR in_stock: true reviews_count: 5 category: "Fiberglass Supply Depot" url: https://www.desertcart.hr/products/692715743-fiberglass-supply-depot-4-lb-density-expanding-pour-foam-2 store_origin: HR region: Croatia --- # 2 cubic feet coverage per 1-gallon kit 5 min full expansion time for fast results 4 lb density for superior flotation support Fiberglass Supply Depot 4 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:** € 629.75 **Availability:** ✅ In Stock ## Summary > 🛠️ Expand Your Projects, Not Your Wait Time! ## Quick Answers - **What is this?** Fiberglass Supply Depot 4 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?** € 629.75 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.hr](https://www.desertcart.hr/products/692715743-fiberglass-supply-depot-4-lb-density-expanding-pour-foam-2) ## 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 - • **Multi-Use Masterpiece:** Ideal for soundproofing, insulation, sculpting, casting, and filling voids—unlock your creative and practical potential. - • **Versatile & Compatible:** Laminates seamlessly with polyester, epoxy, or vinyl ester resins without melting or damage. - • **Buoyant & Built to Last:** 4 lb density foam delivers robust flotation and load support for boats, docks, and more. - • **Rapid Expansion, Minimal Wait:** Fully expands in just 5 minutes, letting you move quickly from application to finishing. - • **Precision Mixing for Perfect Results:** Equal parts Part A & B with a 45-second working time ensures professional-grade application every time. ## Overview Fiberglass Supply Depot’s 4 lb density expanding pour foam is a high-performance 2-part polyurethane kit designed for flotation, soundproofing, insulation, and filling voids. With a quick 5-minute expansion and compatibility with major resins, it covers 2 cubic feet per gallon and supports moderate loads, making it perfect for marine, construction, and creative applications. ## Description This 4LB density foam is suited well for most flotation applications that require more support than the 2LB offers. This foam is recommended to be used when supporting gas tanks and some deck areas. Choose this density if you feel that the foam will be required to withstand minor to moderate loads. The 4LB density also works well in floating decoy or taxidermy applications as well as many other sculpting, casting, carving and other filling applications Review: Crazy foam - Product works great. It takes some trial and error to judge the right amount to mix because it really expands. It’s easy to cut away any excess Review: Great product!!!! - Awesome stuff, I used it to fill holes used from animals going under my cement driveway and walkway. Fantastic results and hardens like a rock ## 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. - 4LB. Density polyurethane flotation Foam 1 Gallon Kit; Consists of 1/2 gallon of Part A and 1/2 gallon of Part B and produces 2 cubic feet. - Once fully cured this foam can be laminated over with any type of polyester, epoxy or vinyl ester resin without melting. - The 4LB 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 ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B08T2195F8 | | Brand | Fiberglass Supply Depot | | Brand Name | Fiberglass Supply Depot | | Country of Publication | USA | | Coverage | 2 cubic feet | | Customer Reviews | 4.4 out of 5 stars 249 Reviews | | Manufacturer | Fiberglass Supply Depot Inc. | | Manufacturer Part Number | FBAPOLY4LBGK | | Material | Foam , Resin | | Material Type | Foam,Resin | | Number of Items | 1 | | Number of Packs | 1 | | Recommended Uses For Product | Flotation, Soundproofing, Insulation, Filling Voids | | UPC | 819794022934 | | Unit Count | 192 Fluid Ounces | ## Product Details - **Brand:** Fiberglass Supply Depot - **Manufacturer:** Fiberglass Supply Depot Inc. - **Material:** Foam,Resin - **Recommended Uses For Product:** Flotation, Soundproofing, Insulation, Filling Voids - **UPC:** 819794022934 ## Images ![Fiberglass Supply Depot 4 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/611pMIJrAfL.jpg) ![Fiberglass Supply Depot 4 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) ![Fiberglass Supply Depot 4 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) ![Fiberglass Supply Depot 4 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) ![Fiberglass Supply Depot 4 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: What is the compressive strength of the foam, in PCF?** A: They only give the compressive strength in PSI and that is 78 for the 4lb foam **Q: What is the viscosity of the liquids before they mix?** A: The best way to describe it would be like warm pancake syrup. **Q: i'm new at this..what does density mean i see 2lb..4lb..6lb? thanks** A: Think of it as hardness or strength. The 2lb will be more sponge like 6 will be harder. **Q: Can you use pole foam to insulate the walls of a shop? Does it go thru a heat? Will it blister the tyvek or metal on the outside?** A: It doesn't fill a very big volume like spray foam. It is very liquid and comes out of any cracks. Will set up hard as a rock though. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Crazy foam *by V***M on 6 May 2026* Product works great. It takes some trial and error to judge the right amount to mix because it really expands. It’s easy to cut away any excess ### ⭐⭐⭐⭐⭐ Great product!!!! *by L***E on 18 October 2025* Awesome stuff, I used it to fill holes used from animals going under my cement driveway and walkway. Fantastic results and hardens like a rock ### ⭐⭐⭐ Not to be used near fuel *by T***N on 11 June 2026* Petrol breaks this product down and absorbs petrol ## Frequently Bought Together - 4 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 - 6 Lb. Density Expanding Pour Foam, 2 Part Polyurethane Closed Cell Liquid Foam for Boats, Dock Flotation, Carving, Soundproofing, Filling Voids, and Insulation (1 Gallon Kit) --- ## 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.hr/products/692715743-fiberglass-supply-depot-4-lb-density-expanding-pour-foam-2](https://www.desertcart.hr/products/692715743-fiberglass-supply-depot-4-lb-density-expanding-pour-foam-2) --- *Product available on Desertcart Croatia* *Store origin: HR* *Last updated: 2026-07-14*